Forecast Discussions mentioning ACARS, received at FSL on 05/02/00

UPPER RIDGE ACROSS THE AREA TODAY WITH WARM TEMPS. MORNING AIRCRAFT SOUNDINGS SHOW 5-8 DEGS F WARMING SURFACE-4K...CURRENT 24HR CHANGE SHOWS TEMPS UP 2-6. TROF APPROACHING 130W WILL CAUSE SOME MINOR THICKNESS FALLS TODAY...WHICH MAY OFFSET CURRENT TRENDS. ZONES HAVE TEMPS UP A COUPLE OF DEGS OVER SUN...AND THIS LOOKS GOOD. OHTERWISE JUST SOME HIGH THIN CIRRUS. SURFACE GRADS WEAK FOR ONLY LIGHT AFTERNOON BREEZES. SHORTWAVE TO MOVE THRU TONITE BRINGING A LITTLE COOLING TUES...MAINLY TO THE VALLEY IN THE FORM OF DELTA PUSH. CURRENT ADVERTISED TMMPS TUES MAY BE TOO LOW BUT WILL ADDRESS THAT IN AFTERNOON PACKAGE. ALL POPS ZERO. BINGHAM

.HNX...NONE.



QUIET DAY ACROSS THE DISTRICT THIS MORNING. MARINE LAYER HAS BEGUN TO MAKE SOME VERY MINOR INROADS THIS MORNING...WITH SOME STRATUS/FOG OVER LONG BEACH AND ACROSS THE CENTRAL COAST. ISSUED NOWCAST EARLIER TO ACCOUNT FOR THIS PATCHY MARINE LAYER...AS IT SHOULD BURN OFF VERY QUICKLY THIS MORNING. SURFACE GRADIENTS ARE MORE ONSHORE THIS MORNING WHICH SHOULD RESULT IN SOME COOLING FOR COASTAL AREAS. HOWEVER... INLAND SECTIONS SHOULD HAVE VERY SIMILAR TEMPS AS SUNDAY.

OVERALL...ZONES HAVE GOOD HANDLE ON EXPECTED SUNNY SKIES AND TEMP TRENDS. DO NOT ANTICIPATE ANY ZONE UPDATES THIS MORNING.

LAX 000. THOMPSON.

.LAX...SMALL CRAFT ADVISORY (SEE LAXCWFLAX).



UPPER RIDGE OVER THE WESTERN U.S. BEGINNING TO FLATTEN OUT AND SHIFT EAST. FIRST SHORT WAVE LIFTING NEWRD ACROSS PUGET SOUND EARLY THIS MORNING WITH A FEW HIGH CLOUDS TRAILING SOUTH INTO NORCAL. NEXT WAVE APPROACHING 40N/140W ATTM WILL SPREAD MORE CLOUDS ACROSS THE NORTHERN PORTION OF THE CWA LATER TODAY AND THIS EVENING. HAVE INCLUDED A SLIGHT CHANCE OF PRECIP ACROSS THE FAR NORTH AS THIS FEATURE MOVES THROUGH...AS SOME INCREASE IN MOISTURE AND INSTABILITY IS INDICATED BY AVN AND ETA. OTHER THAN THAT...SHOULD BE A QUIET WEEK WITH FLAT WESTERLY FLOW ACROSS THE EPAC INTO NORCAL. EXPECT ANOTHER RATHER WARM DAY TODAY MOST AREAS...THEN TEMPS COOL BACK TO NEAR NORMAL THROUGH MIDWEEK AS HEIGHTS ERODE SLIGHTLY AND STRONGER ONSHORE FLOW DEVELOPS. MRF STILL BUILDING A STRONG RIDGE ALONG THE WEST COAST NEXT WEEKEND...BUT THIS LATEST RUN IS NOT AS STRONG WITH THE RIDGE AS THE PREVIOUS TWO. ROWE

.STO...NONE.

BLU UU 065/051 062/048 062 68000 RBL BB 082/056 082/053 081 68110 SAC UU 083/054 081/053 081 68000



UPPER LOW WAS CURRENTLY OVER THE CENTRAL KS/OK BORDER. SHORTWAVE TROUGH WAS ALSO PUSHING AROUND THE SOUTHERN SIDE OF THE LOW...MOVING INTO SOUTHERN TEXAS. AREA SOUNDINGS...INCLUDING THE ACARS/MAPS SOUNDING FOR IAH...ALL SHOW CAPES NEAR OR EXCEEDING 3000 FOR MUCH OF SETX. WITH THIS IN MIND FEEL THAT THE HIGH POPS FOR THE AREA ARE WARRANTED...INCLUDING THE MENTION OF SEVERE AND HEAVY RAINFALL. STRONG THUNDERSTORMS WERE DEVELOPING JUST WEST OF GRK AT THE MOMENT. THESE STORMS WERE DEVELOPING ALONG A SURFACE TROUGH/OUTFLOW BOUNDARY. SURFACE DEWPOINTS ALONG AND AHEAD OF THE BOUNDARY WERE IN THE MID 60S. ALSO...SOUTHEASTERLY WINDS WERE FEEDING GULF MOISTURE INTO THE DEVELOPING STORMS. A SIDE NOTE...THE HGX VWP WAS SHOWING SOUTHWEST WINDS NEAR THE SURFACE...MORE THAN LIKELY THE RESULT OF MIGRATING BIRDS CONTAMINATING THE ALGORITHM RESULTS.

SO...THE CONCLUSION OF THE MATTER IS THAT ANOTHER ROUND OF THUNDERSTORMS ARE EXPECTED. WILL NOT GO WITH A FLASH FLOOD WATCH AT THIS TIME...THOUGH RAINFALL AMOUNTS COULD REACH 1 INCH OR SO OVER A WIDE AREA. LOCATIONS THAT LOOK TO GET THE HEAVIER RAIN AMOUNTS WILL BE THE FAR NORTHERN COUNTIES OF THE FORECAST AREA.

TEMPERATURES AND WINDS ARE THE MOST DIFFICULT OF THE VARIABLES TO FORECAST TONIGHT. GIVEN THE CURRENT DEWPOINTS FEEL THAT THE FORECAST MINS ARE OKAY. WINDS ARE ANOTHER MATTER. VARIABLE TO SOUTHEAST WINDS SHOULD OCCUR AHEAD OF THE THUNDERSTORMS...WITH NORTH WINDS IN ITS WAKE.

WILL ONLY MAKE MINOR CHANGES TO THE COASTAL FORECAST.

.KHGX...NONE.

PL-40 45



UPDATED ZONES WILL BE OUT SHORTLY TO REFLECT CURRENT PRECIP TRENDS. LOBE ROTATING AROUND MID/UPPER LEVEL LOW PROVIDING JUST ENOUGH LIFT IN MID LEVELS TO SQUEEZE OUT SOME LIGHT RAIN SHOWERS ACROSS THE CNTRL AND SRN TX PNHDL. A FEW LOCATIONS MAY BE ABLE TO RECEIVE MEASURABLE PRECIP AMOUNTS SO WILL INTRODUCE POPS. HOWEVER...THINK MOST LOCATIONS WILL RECEIVE TRACE AMOUNTS.

.AMA... TX...NONE. OK...NONE.

JH



SHOWERS AND THUNDERSTORMS ARE INCREASING IN AREAL COVERAGE AS THE SHORTWAVE OVER FAR WEST TEXAS APPROACHES. ALTHOUGH MOST OF THE SEVERE WEATHER WILL REMAIN JUST SOUTH OF THE FORECAST AREA...A FEW STORMS MAY REACH SEVERE LIMITS ACROSS THE EXTREME SOUTH. THUS HAVE ADDED MENTION OF SEVERE THERE. HAVE ALSO ADJUSTED TONIGHTS LOWS A CATEGORY OR SO ACROSS THE SOUTH AS DEWPOINTS REMAIN IN THE 60S. DRIER AIR SHOULD FILTER IN LATE TONIGHT AS THE WINDS BECOME MORE NORTHERLY.

AVIATION DISCUSSION... HAD TO ADD A MENTION OF TEMPO THUNDERSTORMS BETWEEN 2 AND 4Z FOR THE WACO AREA...THIS MAY HAVE TO BE EXTENDED FOR A COUPLE OF HOURS MORE. THUNDERSTORMS HAVE ALSO FORMED SOUTH OF THE DALLAS/FORT WORTH AREA... THIS ACTIVITY WILL LIKELY REMAIN JUST SOUTH OF THE METROPLEX...SO WILL OPT NOT TO ADD THUNDERSTORSM TO METROPLEX FOR NOW. OTHERWISE.. VFR WILL PREVAIL THIS EVENING ACROSS THE METROPLEX...BUT EXPECT CIGS OF BKN-OVC015 AS WRAP AROUND SLOW MOVING UPPER LEVEL LOW. #58

.FTW...NONE.



THE LATEST KSJT REFLECTIVITY LOOP SHOWS A NARROW BAND OF SHOWERS AND THUNDERSTORMS TRAINING ALONG THE STALLED COLD FRONT WHICH WAS LOCATED ALONG A DFW TO JCT LINE. THE ETA DID SHOW A SHORTWAVE ROTATING INTO OUR SRN ZONES THIS EVENING. THE COMBINATION OF THE SYNOPTIC SCALE FORCING... LOW LEVEL CONVERGENCE ALONG THE BOUNDARY... AND MARGINAL INSTABILITY SHOULD ALL BE ENOUGH TO SUSTAIN THE CONVECTION OVER OUR FAR SERN ZONES FOR A FEW MORE HOURS. AS THE UPPER LOW PUSHES FARTHER SOUTH TONIGHT... EXPECT THE COLD FRONT TO MOVE SLOWLY SOUTH ENDING THE CONVECTIVE THREAT. AS A RESULT... WILL UPDATE ZONES TO INCREASE POPS IN THE ERN HEARTLAND AND NORTHWEST HILL COUNTRY FOR EARLY TONIGHT. IN ADDITION... THE SLOWER MOVING COLD FRONT WILL KEEP TEMPS UP OVERNIGHT IN THIS AREA... SO PLAN TO BUMP LOWS UP A CATAGORY OR TWO.

.SJT...NONE.

TEW N 

SATELLITE IMAGERY INDICATES UPPER LOW CENTERED OVER NORTHWEST OKLAHOMA. WATER VAPOR IMAGERY INDICATES SMALL AMPLITUDE SHORT WAVE OVER EXTREME WEST TEXAS...ROTATING AROUND THE UPPER LOW.

WEAK...NEARLY STATIONARY SURFACE BOUNDARY WAS LOCATED NEAR A AUSTIN...TO LUFKIN LINE. SOME ORGANIZED CONVECTIVE DEVELOPMENT IS EXPECTED OVERNIGHT IN THE VICINITY OF THIS BOUNDARY. EXPECT THE BULK OF THIS ACTIVITY TO AFFECT AREAS EAST AND SOUTH OF THE CWA.

UPPER LOW OVER NORTHWEST OKLAHOMA EXPECTED TO MOVE SLOWLY SOUTHEAST AND WEAKEN THROUGH THE SHORT TERM PERIODS. COLD POOL ASSOCIATED WITH THIS FEATURE SHOULD PROMOTE WIDELY SCATTERED TO SCATTERED...MAINLY DIURNAL TSRA ACROSS CENTRAL AND EASTERN PORTIONS OF THE FORECAST AREA THROUGH WEDNESDAY.

UPPER LEVEL PATTERNS EXPECTED TO BECOME MORE ZONAL ACROSS NORTH AMERICA DURING THE EXTENDED PERIODS. DRY CONDITIONS EXPECTED TO PREVAIL BY THE END OF THE WEEK.

FCSTID = 83 DFW 56 76 57 79 / 10 20 10 10 ACT 56 76 59 80 / 30 30 20 20

.FTW...NONE.

...AVIATION DISCUSSION

VFR TO PREVAIL THIS EVENING BEFORE WRAP AROUND CIGS BKN-OVC015 WRAP AROUND SLOW MOVING UPPER LEVEL LOW. THIS IS A BIT ON THE PESSIMISTIC SIDE AS ETA AND FWC KEEP DRY SLOT OVER N TEXAS TONIGHT. HOWEVER...WET GROUND AND NW WINDS SHOULD ALLOW CIGS TO LOWER AFTER MIDNIGHT. EXPECT THUNDER TO REMAIN SOUTH OF KACT BUT MORE LOW CLOUDS WILL MOVE ACROSS THIS AREA AS WELL. 80



SYNOPSIS... HERE IS THE BORDERLAND WEATHER SYNOPSIS. AN UPPER LEVEL LOW CURRENTLY OVER THE TEXAS PANHANDLE WILL SLOWLY SLIDE SOUTHEAST ACROSS TEXAS AND AWAY FROM THE AREA. THIS WILL ALLOW AN UPPER LEVEL RIDGE TO FORM OVER THE SOUTHWEST. UNDER THE RIDGE TEMPERATURES WILL WARM DAY TO DAY THROUGH THE END OF THE WEEK. BY THURSDAY LOWLAND TEMPERATURES WILL BE BACK IN THE MID 90S. WINDS WILL STAY LIGHT AND SKIES WILL REMAIN RELATIVELY CLOUD FREE.

DISCUSSION... WATER VAPOR SATELLITE IMAGERY SHOWING UPPER LOW SPINNING OVER TX/OK PANHANDLES THIS AFTERNOON. AVN/ETA/NGM IN AGREEMENT IN SAGGING THIS FEATURE SOUTH ACROSS TX. THAT WOULD HELP KEEP TEMPS OVER THE EL PASO FORECAST AREA (FA) SLIGHTLY COOLER AS RIDGE BUILDING OUT WEST IS HELD AT BAY. LOOKING AT H250 WINDS BELIEVE THE LOW WILL PULL OUT SOONER AND TAKE A MORE EASTERN TRACK. STILL, EFFECTS ON FA ARE MINIMAL AS THE WEEK WILL SEE ANOTHER SIGNIFICANT WARMING AS STRONG HIGH PRESSURE BUILDS OVER THE SOUTHWEST ON THE HEELS OF THE EXITING LOW. SHOULD KEEP EAST COMPONENT TO WINDS THIS EVE AND TONIGHT...BUT LIGHT ENOUGH TO ALLOW TEMPS TO BE COOLER THAN SEEN IN SOME WEEKS. WITH HIGH PRESSURE OVER THE AREA AND LOW EXITING...WILL SEE LIGHTER WINDS FOR THE WEEK AND A DRYING OF THE ATMOSPHERE.

IN THE EXTENDED...MRF VERY AGGRESSIVE IN BUILDING A STRONG HIGH OVER THE REGION...OTHER MODELS SUCH AS ECMWF, NOGAPS, AND CANADIAN NOT NEAR AS STRONG...BUT DO BUILD A HIGH...THIS WILL KEEP IT WARM AND DRY.

EL PASO UU 48/ 86/ 54/ 90/ 58 00000 LAS CRUCES UU 44/ 85/ 51/ 89/ 54 00000 ALAMOGORDO UU 42/ 83/ 48/ 87/ 52 00000 CLOUDCROFT UU 25/ 62/ 31/ 66/ 35 00000 TRUTH OR CONSEQUENCES UU 41/ 84/ 47/ 88/ 51 00000 SILVER CITY UU 33/ 75/ 39/ 79/ 43 00000 DEMING UU 42/ 85/ 48/ 89/ 53 00000 LORDSBURG UU 41/ 84/ 48/ 88/ 54 00000 SIERRA BLANCA UU 47/ 84/ 53/ 88/ 56 00000

.ELP...NONE

14 / BIRD

N 

SATELLITE IMAGERY SHOWS AN UPPER LEVEL LOW CHURNING OVER NORTHWEST OKLAHOMA PRESENTLY. THIS UPPER LOW IS EXPECTED TO MOVE SOUTH SOUTHEAST INTO NORTH TEXAS BY TOMORROW AFTERNOON. AN ASSOCIATED 500 MB COLD POOL LOCATED NEAR THE UPPER LOW OVER THE BIG COUNTRY SHOULD ALLOW FOR SOME CU TO FORM ACROSS THE NORTHEAST AND EAST PORTIONS OF THE FORECAST AREA ON TUESDAY. WITH DAYTIME HEATING...I WOULD NOT RULE OUT A SHOWER FOR THIS AREA.

THE UPPER LOW WILL GRADUALLY SLIDE EAST OF THE AREA...WITH ASSOCIATED SFC LOW PRESSURE ALSO MOVING EAST OF THE AREA BY WEDNESDAY MORNING. SFC LEE TROFFING WILL SET UP BY WEDNESDAY WITH SOUTHEAST SFC WINDS FORECAST EAST OF THE MOUNTAINS ALONG WITH INCREASING LOW LEVEL MOISTURE. THIS WILL LEAD TO WARMER NIGHTTIME TEMPERATURES. IN FACT...A GENERAL WARMING TREND IS EXPECTED INTO THE EXTENDED PERIOD AS AN UPPER LVL RIDGE INTENSIFIES OVER THE WEST TEXAS AND NEW MEXICO.

PRELIMINARY CCF...

MAF 48/75/52/84 0000 LSA 46/74/50/83 0110 E41 49/76/55/81 0210 6R6 54/78/59/87 0--0 MRF 42/76/45/83 0000 CNM 47/77/49/89 0000

.MAF... TX...NONE. NM...NONE.

VESPER/03



SATELLITE IMAGERY INDICATES UPPER LOW CENTERED OVER NORTHWEST OKLAHOMA. WATER VAPOR IMAGERY INDICATES SMALL AMPLITUDE SHORT WAVE OVER EXTREME WEST TEXAS...ROTATING AROUND THE UPPER LOW.

WEAK...NEARLY STATIONARY SURFACE BOUNDARY WAS LOCATED NEAR A AUSTIN...TO LUFKIN LINE. SOME ORGANIZED CONVECTIVE DEVELOPMENT IS EXPECTED OVERNIGHT IN THE VICINITY OF THIS BOUNDARY. EXPECT THE BULK OF THIS ACTIVITY TO AFFECT AREAS EAST AND SOUTH OF THE CWA.

UPPER LOW OVER NORTHWEST OKLAHOMA EXPECTED TO MOVE SLOWLY SOUTHEAST AND WEAKEN THROUGH THE SHORT TERM PERIODS. COLD POOL ASSOCIATED WITH THIS FEATURE SHOULD PROMOTE WIDELY SCATTERED TO SCATTERED...MAINLY DIURNAL TSRA ACROSS CENTRAL AND EASTERN PORTIONS OF THE FORECAST AREA THROUGH WEDNESDAY.

UPPER LEVEL PATTERNS EXPECTED TO BECOME MORE ZONAL ACROSS NORTH AMERICA DURING THE EXTENDED PERIODS. DRY CONDITIONS EXPECTED TO PREVAIL BY THE END OF THE WEEK.

FCSTID = 83 DFW 56 76 57 79 / 10 20 10 10 ACT 56 76 59 80 / 30 30 20 20

.FTW...NONE.



THE 17Z WATER VAPOR SATELLITE IMAGERY SHOWS AN UPPER LEVEL LOW CENTERED OVER THE OK PANHANDLE. AN UPPER LEVEL RIDGE WAS LOCATED OVER THE WESTERN HALF OF THE CONUS...WHILE AN UPSTREAM TROUGH WAS AMPLIFYING OVER THE EASTERN PACIFIC. AN UPPER LEVEL SHORTWAVE TROUGH WAS DIGGING SOUTHEAST ACROSS THE UPPER GREAT LAKES.

THE 17Z SURFACE OBSERVATIONS SHOW A WEAK SURFACE LOW OVER WESTERN MISSOURI WITH A TRAILING COLD FRONT EXTENDING SOUTH-SOUTHWEST ACROSS CENTRAL OK INTO CENTRAL TX.

THIS AFTERNOON...SKIES WERE MOSTLY SUNNY OVER THE SOUTHWESTERN SECTIONS OF THE FORECAST AREA AND MOSTLY CLOUDY OVER THE NORTHEAST SECTIONS. THE LOW AND MID-LEVEL CLOUDS ROTATING AROUND THE UPPER LOW OVER EASTERN NM HAVE BEEN DISSIPATING AS THEY MOVE SOUTHEAST ONTO THE LOWER TERRAIN DUE TO SUBSIDENCE...AS THE AIR PARCELS MOVE EAST FROM HIGHER TO LOWER TERRAIN. WITH A POCKET OF COLD AIR ALOFT IN THE VICINITY OF THE UPPER LEVEL LOW...AFTERNOON HEATING ALONG WITH RESIDUAL MOISTURE WILL CAUSE CUMULUS CLOUDS TO DEVELOP ACROSS THE FORECAST AREA. IF ENOUGH CAPE IS AVAILABLE...PERHAPS AN EVENING SHOWER OR THUNDERSTORM MAY DEVELOP. THE BEST CHANCE FOR LATE AFTERNOON AND EVENING SHOWERS OR THUNDERSTORMS WILL OCCUR OVER THE NORTH-CENTRAL AND NORTHEAST SECTION OF THE FORECAST AREA CLOSER TO THE UPPER LEVEL LOW WHERE 500MB TEMPERATURES WILL RANGE FROM -17 T0 -19 DEGREES...ALSO THERE WILL BE LESS SUBSIDENCE. AT THIS TIME I WILL CARRY A SLIGHT CHANCE OF SHOWERS OR THUNDERSTORMS ACROSS THE NORTH-CENTRAL AND EASTERN SECTIONS OF THE FORECAST AND KEEP SKIES PARTLY CLOUDY TONIGHT. IF BY ZONE ISSUANCE THE CU FIELD DOESN'T SHOW MUCH VERTICAL GROWTH I MAY PULL THE SLIGHT CHANCE FOR A SHOWER OR THUNDERSTORM THIS EVENING. OVER THE SOUTH-CENTRAL AND WESTERN SECTIONS OF THE FORECAST AREA I WILL GO WITH MOSTLY CLEAR SKIES AS THE DOWNGLIDE SHOULD DISSIPATE THE LOW CLOUDS. THERE MAY BE A FEW PASSING HIGH AND MID-LEVEL CLOUDS. ANY CUMULUS CLOUDS AND SHOWERS THAT DO FORM ACROSS THE FORECAST AREA WILL DISSIPATE AFTER SUNSET.

THE ETA MODEL SHOWS THE UPPER LEVEL LOW DIGGING SOUTHEAST INTO WESTERN OK DURING THE DAY TUESDAY. THE RIDGE AXIS OVER THE WESTERN US WILL BUILD NORTHEAST OVER THE CENTRAL PLAINS. THE UPPER LEVEL CLOSED LOW OVER OK WILL BE CUT OFF FROM THE WESTERLY ZONAL FLOW FORMING A MINOR REX BLOCK. 500-1000 MB THICKNESSES WILL INCREASE TOMORROW AFTERNOON ALLOWING TEMPERATURES TO WARM INTO THE 70S ACROSS THE FORECAST AREA. THERE MAY BE A SLIGHT CHANCE OF AN AFTERNOON SHOWER OR THUNDERSTORM TUESDAY AFTERNOON OVER THE EASTERN SECTIONS OF THE FORECAST AREA SINCE THE WESTERN EDGE OF THE MID-LEVEL COLD POOL WILL BE OVER THE EASTERN COUNTIES. I WILL STICK A 20 POP IN THE EASTERN COUNTIES OF THE FORECAST AREA FOR TUESDAY AFTERNOON. BY 48 HOURS THE ETA MODEL FORECAST THE UPPER LEVEL CLOSED LOW TO MOVE SOUTHEAST INTO EASTERN TX AND FILL. AFTERNOON HIGHS WILL WARM INTO THE 80S ON WEDNESDAY AS THE 500-1000MB THICKNESSES INCREASE AND THE UPPER LEVEL RIDGE AXIS MOVES CLOSER TO THE REGION.

EXTENDED OUT LOOK: THE MRF...ECMWF AND CANADIAN MODEL SOLUTIONS ARE SIMILAR KEEPING THE UPPER LEVEL JET STREAM OVER THE NORTHERN US AND SOUTHERN CANADA WITH THE RIDGE AXIS AMPLIFYING OVER THE CENTRAL CONUS. EXPECT DRY AND WARM CONDITIONS TO CONTINUE THROUGH THE END OF THE WEEK.

FRIONA 42/74/46/82 1-00 LUBBOCK 44/74/47/83 --00 TULIA 43/72/46/82 11-0 BROWNFIELD 44/76/47/85 --00 CHILDRESS 46/70/50/80 1210 ASPERMONT 49/72/52/82 1210

.LBB...NONE.

20



UPPER LOW NEAR THE TEXAS PANHANDLE-WESTERN OKLAHOMA BORDER WILL WEAKEN AND SLOWLY DRIFT TOWARD SOUTHEAST TEXAS THROUGH THURSDAY. ENERGY ROTATING AROUND THE LOW WILL IGNITE SHOWERS AND THUNDERSTORMS LATER THIS AFTERNOON AND TONIGHT TO OUR WEST AND SOUTHWEST. ACTIVITY WILL ORGANIZE INTO ANOTHER MCS AND DRIFT TO THE SOUTHEAST AND EAST OVERNIGHT. MODELS INDICATE GOOD UVM VALUES...HIGH MOISTURE LEVELS (PW VALUES 1.50 TO 1.75 INCHES)...AND A FOCUSING BOUNDARY (OLD OUTFLOWS AND FRONTAL BOUNDARY OVER SOUTH CENTRAL TEXAS) IN THE AREA. STILL UNCERTAIN AS TO WHICH EXACT ROUTE THE MCS WILL TAKE...BUT SOME IF NOT ALL OF OUR AREA HAS A GOOD SHOT OF SEEING MORE STORMS TONIGHT AND TOMORROW MORNING. CANNOT RULE OUT THE THREAT FOR SOME HAIL AND STRONG WINDS WITH THE STRONGER STORMS SO WILL INCLUDE THE MENTION OF SEVERE IN THE FIRST PERIOD. WILL ALSO MENTION LOCALLY HEAVY RAIN THREAT FOR BOTH TONIGHT AND EARLY TOMORROW MORNING. EXPECT MOST AREAS TO SEE UP TO AN INCH OF RAIN WITH ISOLATED SPOTS POSSIBLY GETTING 3 TO 4 INCHES. WILL HOLD OFF ON A FLASH FLOOD WATCH SINCE RAINS FROM EARLIER TODAY HAVE HAD TIME TO RECEDE/DISSIPATE. WOULD PREFER TO SEE WHERE THE MCS DEVELOPS BEFORE JUMPING ON A WATCH.

AS THE UPPER LOW CONTINUES TO HEAD THIS WAY...EXPECT A BREAK FROM THE STORMS TOMORROW AFTERNOON THEN ANOTHER SHOT TUESDAY NIGHT/ WEDNESDAY MORNING. THERE'S A CHANCE WE COULD HAVE THIS ON-AGAIN/ OFF-AGAIN TYPE OF SHOWERS AND THUNDERSTORMS THROUGH THE REST OF THE WEEK AS THE MEDIUM RANGE MODELS KEEP THE UPPER LOW IN OUR VICINITY. WILL KEEP A CHANCE OF RAIN THROUGH THE EXTENDED FORECAST. PRELIMS ARE NEXT.

.KHGX...NONE.

42/37/35

PRELIMS... CLL TT 063/077 062/080 064 42766 IAH TT 066/078 065/081 065 42766 GLS TT 072/078 070/079 070 42766



MAIN STORY TONIGHT WILL BE THE TRACK OF MID/UPPER LEVEL LOW CURRENTLY LOCATED BETWEEN WICHITA KANSAS AND GAGE OKLAHOMA. MODELS TRACK LOW CENTER TOWARDS THE RED RIVER AREA BY 12Z TUESDAY AND THEN OVER NORTHEAST TEXAS TUESDAY AFTERNOON. 12Z AVN A BIT MORE PROGRESSIVE NEAR LAWTON OK COMPARED TO THE SLOWER NGM NEAR ALTUS BUT DECENT AGREEMENT NONETHELESS. STILL EXPECT SOME WRAP AROUND ENERGY TO BRUSH THE EASTERN ZONES TONIGHT BEFORE PRECIP ENDS BY TUESDAY AFTERNOON. REFLECTIVITY IMAGERY INDICATES SOME LIGHT RETURNS OVER PORTIONS EASTERN ZONES. PLAN TO HOLD ON TO LOW CHANCE POPS OUT EAST TONIGHT WITH A DRY FORECAST OVER WESTERN ZONES.

12Z MODELS ALSO INDICATE ISENTROPIC DOWNGLIDE ALONG THE 295 K SURFACE BY 12Z TUESDAY SO WOULD NOT EXPECT MUCH IN THE WAY OF FOG DEVELOPMENT AFTER MIDNIGHT. NORTH WINDS TONIGHT MAY BECOME LIGHT AND VARIABLE TOWARDS SUNRISE AS SURFACE HIGH SETTLES OVER THE PANHANDLES. SURFACE HIGH WILL SLIDE EAST OF THE AREA TUESDAY NIGHT AS LEE TROF REDEVELOPS OVER EASTERN COLORADO. WAA PATTERN AND LOW LEVEL JET SHOULD BECOME REESTABLISHED OVER THE SOUTHERN HIGH PLAINS WEDNESDAY AND ESPECIALLY WEDNESDAY NIGHT.

EXTENDED...SEVERE WEATHER ON SATURDAY SEEMS TO BE A REOCCURING THEME FOR THE PANHANDLES DURING THE PAST 4 SATURDAYS. LATEST MRF KEEPS THIS STRING OF STORMY SATURDAYS GOING. A NORTHERN STREAM SHORTWAVE WILL DISLODGE ANOTHER COLD FRONT INTO THE SOUTHERN PLAINS SATURDAY NIGHT WHILE MOST OF THE UPPER ENERGY REMAINS NORTH OF THE PANHANDLES. HOWEVER...MOIST THERMAL ADVECTION PATTERN ASSOCIATED WITH THE LOW LEVEL JET WILL BE WELL ESTABLISHED BY THURSDAY. AIRMASS OVER THE REGION SHOULD BE WELL PRIMED WHEN FRONT REACHES THIS AREA BUT EXPECT CAP TO BE FAIRLY STRONG UNDER THE WARM RIDGE. WILL INTRODUCE CHANCE POPS SATURDAY OVER EASTERN ZONES WITH SLIGHT CHANCE WESTERN ZONES WHICH MAY BE WEST OF THE DRYLINE. STAY TUNED FOR MORE INFO.

PRELIM... AMA 40/70 49/80 55 -00 DHT 40/72 47/82 53 000

.AMA... TX...NONE. OK...NONE.

SLATTERY



LATEST WATER VAPOR IMAGERY SHOWS AN UPPER LOW SPINNING SLOWLY SOUTHWARD ACROSS THE SOUTHEASTERN TEXAS PANHANDLE TOWARD NORTH CENTRAL TEXAS. AT THE SURFACE....COLD FRONT HAS PUSHED SOUTH OF THE AREA AND WAS LOCATED FROM NEAR COLLEGE STATION TO EAST OF AUSTIN NEAR LAREDO. A LINE OF WEAK SHOWERS AND THUNDERSTORMS HAS LINGERED ACROSS SOUTHERN KIMBLE AND MASON COUNTIES ALL DAY TODAY AND MAY CONTINUE FOR A COUPLE HOURS THIS EVENING.

FOR THE MOST OF THE AREA...FORECAST SHOULD BE DRY FOR THIS EVENING WITH SATELLITE SOUNDINGS SHOWING A STABLE AIRMASS ACROSS ALL BUT THE FAR SOUTHEAST. WITH LINGERING SHOWERS OVER THE NORTHWEST HILL COUNTRY...WILL CONTINUE SLIGHT CHANCE POPS FOR THIS EVENING. MODELS ALL BRING UPPER LOW VERY SLOWLY SOUTHEASTWARD...WITH LOW CENTERED JUST EAST OF ABILENE BY TOMORROW AFTERNOON AND SOUTH OF DALLAS FT WORTH BY WEDNESDAY AFTERNOON. AT THE SURFACE...HIGH PRESSURE WILL BUILD IN ACROSS THE NORTHERN HALF OF WEST CENTRAL TEXAS TONIGHT AND CONTINUE TO REMAIN IN CONTROL THROUGH EARLY WEDNESDAY. DESPITE THE UPPER LOW IN THE AREA...RELATIVELY DRY AIRMASS AND LACK OF BOUNDARIES SHOULD LEAD TO A GENERALLY DRY FORECAST FOR TUESDAY AND WEDNESDAY. AM STILL A LITTLE CONCERNED ABOUT EASTERN COUNTIES WITH REMNANT OUTFLOW BOUNDARIES FROM PREVIOUS STORMS AND VICINITY OF COLD UPPER LOW...SO WILL CONTINUE SLIGHT CHANCE PRECIP FOR THAT AREA. OTHERWISE...SHOULD SEE ONE MORE DAY OF SLIGHTLY BELOW NORMAL TEMPERATURES FOR TUESDAY WITH A WARMUP BEGINNING ON WEDNESDAY. LEE TROUGH BEGINNING TO TAKE SHAPE WEDNESDAY AFTERNOON WILL BRING A RETURN OF SOUTHEASTERLY WINDS TO THE AREA.

IN THE EXTENDED...UPPER LOW LINGERS NEAR SOUTHEAST TEXAS COAST THROUGH SATURDAY. DRYLINE OVER FAR WEST TEXAS TRIES TO MOVE INTO THE AREA FRIDAY AND SATURDAY AFTERNOON. WITH MOISTURE BACK ACROSS THE AREA AND WEAK UPPER LOW STILL IN THE NEIGHBORHOOD...CAN NOT RULE OUT A FEW STORMS ALONG THE DRYLINE FOR THE END OF THE WEEK. WILL CONTINUE WITH SLIGHT CHANCE POPS IN THE EXTENDED.

PRELIMS... ABI 051/075/055/083 0-11 SJT 050/077/054/085 0-11 JCT 051/077/054/086 2-21

.SJT...NONE. 08 N 

INTERESTING 24 TO 36 HOURS COMING UP. AS EXPECTED...ENVIRONMENT IS STILL IN STATE OF RE-ADJUSTMENT AFTER MCS MOVED TO EAST JUST NORTH OF CWFA. GOOD OUTFLOW MOVED THROUGH CWFA THIS MORNING BRINGING GUSTY EAST WINDS AND DROPPING DWPTS INTO MID 60S. NEXT SHORT WAVE TROUGH IS BACK NEAR ELP PER WV LOOP AND THIS SHOULD BRING CONVECTION FURTHER SOUTH IN THIS ROUND. FRONT IS DIFFICULT TO FIND BUT APPEARS TO BE JUST NORTH OF SAT TO JUST SOUTH OF DRT. CONVECTION IS ALREADY STARTING TO REFIRE IN THIS AREA. MODELS SOLNS ARE FAIRLY CLOSE WITH BULLEYES IN VERTICAL MOTION AND DIVERGENCE FIELDS BY MIDNIGHT TONIGHT. NGM IS HAVING SFC FEATURE PROBLEMS AND WILL NOT USE. WITH 500 HPA LOW FCST TO REMAIN OVER TX...BUT DRIFT SOUTHEAST...WILL LEAVE CLOUDS AND PRECIP IN FCST THROUGH WEDNESDAY NIGHT. WILL TREND TEMPS DOWN NEXT FEW DAYS DUE TO RAIN COOLED AIR. GUIDANCE TEMPS REALLY NOT OF MUCH USE DUE TO CONVECTION. WILL ISSUE SPS FOR POTENTIAL HEAVY RAIN TONIGHT. NOT AN ENORMOUS AMOUNT OF COOLING AT 500 HPA...SO SEVERE THREAT IS APPEARS LIMITED TO LOCALIZED WIND EVENTS.

EXTENDED...MRF APPEARS TO BE BACKING OFF FROM YESTERDAY'S UNREALISTIC SOLN OF RETROGRADING THE CLOSED LOW OVER TX INTO MEXICO. IT HAS COME AROUND TO A GRADUAL EASTWARD DRIFT TO THE 500 HPA LOW. THIS SHOULD SHUTDOWN PRECIP CHANCES IN EXTENDED PERIOD...SO WILL MAINTAIN A DRY EXTENDED FOR NOW.

MARINE...WILL MAINTAIN SCA FOR TONIGHT AS 30KT LLJ WILL REMAIN OVER AREA. WIND SPEEDS WILL DECREASE TO BELOW SCA AROUND 12Z...AS LLJ MOVES OUT OF AREA...AND COLD FRONT APPROACHES AND BECOMES STATIONARY. WILL KEEP POPS IN THRU WED...BUT ONLY ISOLATED ON TUES NIGHT AND WED AS FRONTOLYSIS OCCURS AND FLOW REMAINS ONSHORE. WW3 WAVE HGTS ARE A BIT LOW AND WILL KEEP SEAS AT 8 FEET TONIGHT AND SUBSIDE THEM BY TUE NIGHT.

PRELIMS... CRP TE 067/079 067/082 068 663 VCT TE 064/077 065/082 068 773 LRD TE 067/080 066/085 065 643

.CRP...SCA GMZ230-250-255-270-275.

78/91/75



SATELLITE PIC HAS AMPLY MID AND HIGH CLOUDS AND MOISTURE CONTINUING FROM THE WEST OVER THE CWA. RAIN AND CONVECTIVE ACTIVITY OCCURRING WITH THE MCS LAST NIGHT AND THIS MORNING HAVE MOVED NORTHEAST. HIGH PRESSURE RIDGE OVER COLORADO IS SLIDING SOUTHEAST...LOW PRESSURE OVER EASTERN OKLAHOMA/ARKANSAS MOVING NORTHEAST...FRONT OVER HILL COUNTY BEGINNING TO SLOWLY SLID EASTWARD THROUGH REMAINING CWA. ALL THIS LEADS ME TO BELIEVE THAT CONVECTIVE ACTIVITY WILL CONTINUE OVER THE CWA THROUGH TONIGHT AND INTO TUESDAY AS A OVER-RUNNING CONDITIONS PREVAILS...HOWEVER BRIEF AND ISOLATED IT MAY BE.

FRONT NOT MOVING FAST ENOUGH TO CLEAR THE CWA BEFORE TONIGHT AS GULF HIGH DEW-POINTS VALUES INFLOW CONTINUES TO SLIDE NORTH UP OVER HILL COUNTRY COUNTIES AND PORTIONS OF SOUTH CENTRAL SECTIONS. ISOLATED CONVECTIVE ACTIVITY CONTINUES TO FIRER ALONG BOUNDARIES CREATED FROM THE EARLIER ACTIVITY.

EXPECT CONVECTIVE ACTIVITY TO INCREASE TONIGHT. SURFACE DEW-POINT DRIER IN THE WESTERN COUNTIES BUT STILL REMAIN IN THE 60S OVER THE EASTERN SECTIONS.

WILL KEEP ISOLATED BRIEF LOCALLY HEAVY RAIN AND SEVERE WEATHER THREAT FOR TONIGHT'S FORECAST. AS SPC STILL HAS SEVERE MENTION FOR ENTIRE CWA MONDAY NIGHT.

EXTENDED FORECAST...WEDNESDAY THROUGH FRIDAY STILL HAS CWA UNDER MOSTLY CLOUDY SKIES...20 TO 30 PERCENT POPS.

PRELIMINARY NUMBERS...

DRT 62/81/62/85 3222 AUS 61/74/61/80 4332 SAT 60/76/62/82 4322

.EWX...NONE.



DO NOT PLAN TO CHANGE FORECAST MUCH. STORM CHANCES HERE APPEAR SIGNIFICANT AS UPPER LOW IN OKLAHOMA MEANDERS SOUTHEAST THE NEXT SEVERAL DAYS. LOW HAS A CONVECTIVE HISTORY. FOR A PERIOD...BACK SIDE OF THE LOW WILL BE UNSTABLE BEFORE AIR SUBSIDES AND DRIES WEST OF THE LOW. BEST CHANCES FOR RAIN HERE SEEM TO BE TONIGHT AND TOMORROW AS LOW LEVEL GULF AIR FEEDS THE MONSTER ALOFT NEARBY BEFORE CONVERGENT AREA SHIFTS NORTHEAST TOMORROW AFTERNOOON.

WILL LOWER MARINE FLAGS AS GRADIENT CONTINUES TO WEAKEN.

BRO TB 073/086 070/084 070 62553 MFE TB 072/088 071/088 070 62553 RGC TB 070/089 066/089 067 62553 SPI TB 076/082 075/082 076 62553

.WFO BRO INTERNET ADDRESS... WWW.SRH.NOAA.GOV/BRO

.BRO...NONE.



AVIATION DISCUSSION...EXPECT SOME CLEARING OF MVFR CEILINGS ACROSS THE DFW SITES BEFORE 21Z...PER SATELLITE IMAGERY AND LATEST RUC OUTPUT. EXPECT WEST-NORTHWEST WIND TO PREVAIL THROUGH 12Z. PRECIPITATION CHANCES TOO LOW TO WARRANT MENTION IN TAF.

COORD. WITH CWSU ZFW.

83

1110 AM CDT MON MAY 01 2000

UPDATED ZONES TO DROP SEVERE AND HEAVY RAIN THREAT AND ALSO MAKE CHANGES TO POPS AND WINDS.

.FTW...NONE

59



BASICALLY JUST UPDATED WRN AND SRN SXNS TO LWR POPS THIS AFTN. SOME SHRA/S MOVG SWD OUT OF THE CNTRL OK PNHDL INTO THE N-CNTRL TX PNHDL...BUT THESE ARE WKNG AND DSIPTG AS THEY CONT MOVG SWD THRU THE CNTRL TX PNHDL. KEPT POPS ALONE ACRS THE N-CNTRL AND NERN SXNS OF THE FA. ALSO...BUMPED UP WNDS EVERYWHERE INTO CAUTION CRITERIA OF 15-25 MPH RANGE. UPR LOW LOCATED W OF KP28 AND S OF KDDC IN SWRN KS ATTM WHICH IS FCSTD TO DIG SWD TDA INTO NWRN OK. PRES GRAD TIGHT ACRS THE PNHDLS AS SFC RDG BUILDS DOWN INTO THE FA AND CAA CONTS. OTRW...NO OTR CHGS TO PREV FCST.

.AMA... TX...NONE. OK...NONE.

SCHNEIDER



UPDATED ZONES TO DROP SEVERE AND HEAVY RAIN THREAT AND ALSO MAKE CHANGES TO POPS AND WINDS.

.FTW...NONE

59



CHECKING THE LATEST GOES SOUNDING...LOOKS LIKE THE ONLY CHANCE FOR AFTERNOON CONVECTION WILL BE IN THE NW HILL COUNTRY AND PERHAPS THE EASTERN HALF OF THE HEARTLAND. HAVE REMOVED POPS IN ALL OTHER COUNTIES.

.SJT...NONE.

15 N N 

UPPER LOW APPEARS TO BE CENTERED IN THE VICINITY OF THE WESTERN OK PANHANDLE. EXPECT THE LOW TO MAKE VERY LITTLE PROGRESS TOT HE EAST TODAY. COLD POOL ALOFT WILL HELP IN THE DEVELOPMENT OF AT LEAST SOME CUMULUS THIS AFTERNOON...AND MAYBE A SHOWER OR TWO. ONLY CHANGE TO THE ZONES WILL BE FOR THE MORNING WORDING TO THE CLOUD COVER OVER THE EASTERN ZONES.

.LBB...NONE. MM



UPDATE TO REMOVE ANY MORNING LOW CLOUD MENTION. 12Z MON MAF MODIFIED SOUNDING INDICATING LITTLE POTENIAL FOR CONVECTION THIS AFTERNOON. GOING DRY FORECAST REASONABLE.

12



OVERNIGHT MCS SHOWING CONSIDERABLE WEAKENING THIS TREND MORNING WITH WARMING CLOUD TOPS...DECREASING LIGHTNING...AND A DECREASE IN OVERALL RADAR ACTIVITY. THINKING THIS MORNING IS THAT CURRENT SOUTHEAST TEXAS ACTIVITY WILL CONTINUE TO DECREASE IN COVERAGE AND INTENSITY. IN THE HILL COUNTRY...A COUPLE LINES OF CONVECTION CONTINUE TO FIRE. EXPECT THIS ACTIVITY TO INCREASE LATER THIS AFTERNOON AND THIS EVENING AS THE UPPER LOW CONTINUES TO SAG SOUTHWARD INTO TEXAS. IT APPEARS THAT THIS WILL PLACE PORTIONS OF SOUTHEAST TEXAS AND THE COASTAL BEND IN VERY STRONG UPWARD VERTICAL MOTION TONIGHT RESULTING IN AN INCREASING HEAVY RAIN AND SEVERE WEATHER THREAT. WILL CONTINUE TO MONITOR PRESENT ACTIVITY AS A LOT OF UNCERTAINTY STILL EXISTS DUE TO BOUNDARIES CREATED FROM THIS FIRST MCS.

WILL MAKE SOME ZONE ADJUSTMENTS. WILL LOWER FIRST PERIOD POPS AREAWIDE. WILL CALL FOR FIRST PERIOD WINDS TO COME BACK AROUND TO THE SOUTHEAST. WILL KEEP LOCALLY HEAVY RAIN AND SEVERE WEATHER THREAT INTACT FOR TONIGHT.

.KHGX...SCEC BAYS AND 0-60 NM.

42/37/35

PRELIMS... CLL CT 077/064 077/062 079 476 IAH CT 077/067 078/064 080 466 GLS CC 077/073 078/072 078 355



ATMOSPHERE WILL BE IN A STATE OF RE-ADJUSTMENT UNTIL AT LEAST MID AFTERNOON AS MCS TO NORTH CONTINUES TO MOVE EAST. ONLY FAR NORTHERN AND NORTHEAST CWFA WERE CLIPPED BY THIS WITH NO SEVERE WEATHER. AREA SOUNDINGS HAVE A FAIRLY GOOD CAP IN PLACE AND AS A FORMER FORECASTER HERE ONCE SAID "AN ENORMOUS AMOUNT OF WASTED CAPE". STILL EXPECT "BIG SHOW" TONIGHT AS MORE VIGOROUS SHORT WAVE TROUGH APPROACHES FROM NORTHWEST. WILL REWORD POPS/PRECIP FOR LATE AFTERNOON. WINDS ARE "CONFUSED" WITH OUTFLOW BOUNDARIES AROUND. EXPECT MEAN SYNOPTIC FLOW TO START AGAIN BY MID-AFTERNOON. WILL MAKE SOME WIND ADJUSTMENTS TO INLAND BAYS AND WATERWAYS ON MARINE FORECAST...OTHERWISE IT IS OK.

.CRP...SCA GMZ230-235-250-255-270-275.

78



.DISCUSSION...MORNING SOUNDING AT BRO SHOWS GOOD POTENTIAL FOR CONVECTIVE ACTIVITY. A CAPE OF NEAR 5000 J/KG AND LI OF -12 SET THE STAGE FOR LATER ACTIVITY HERE. PWAT IS A MODERATE 1.22 INCHES. SPC HAS THE ENTIRE CWA IN A SLIGHT RISK AREA. CURRENTLY WATCHING A WIND SHIFT LINE MOVE THROUGH DEEP SOUTH TEXAS WHILE THE BULK OF THE REMAINING OVERNIGHT ACTIVITY BEGINS TO LIFT TO THE NORTH OF HERE. EXPECT SOMETHING TO POSSIBLY POP UP THIS AFTERNOON AS THE MESOETA SHOWS PVA PARCELS BEGINNING TO ADVECT OVER DEEP SOUTH TEXAS. BY THIS EVENING STRONG PVA WILL PROVIDE AMPLE TRIGGER FOR CONVECTION AS THE UPPER LOW SAGS OVER NORTH TEXAS. FOR THIS MORNING WATCHING SURFACE WINDS AS A 55 KT LOW LEVEL JET MIXES DOWN WITH DAYTIME SURFACE HEATING. CURRENT PACKAGE LOOKS ON TRACK FOR NOW...THE AFTERNOON SHIFT WILL BE IN A BETTER POSITION TO FINE TUNE FOR LATER TODAY. WILL STILL MONITOR FOR WINDS HOWEVER...AND ADJUST IF NECESSARY.

.MARINE...WILL KEEP THE SCA UP FOR ALL COASTAL ZONES AS A NORTHWEST MEXICAN SURFACE LOW WILL HELP KEEP THE GRADIENT UP THROUGH TODAY.

WILL ISSUE AN UPDATED HAZARDOUS WEATHER OUTLOOK LATER THIS MORNING.

SYNOPTIC...54.BHM/HMT...ABBOTT

WFO BRO INTERNET ADDRESS...WWW.SRH.NOAA.GOV/BRO

.BRO...SCA GMZ130-150-155-170-175.



CLOUD DECK HAS MOVED OUT OF NORTHERN AND WESTERN COUNTIES...WILL KEEP MOSTLY CLOUDY OVER NORTHWEST HILL COUNTRY AND HEARTLAND AND UPDATE WITH PARTLY CLOUDY ELSEWHERE. THE REST LOOKS OK FOR NOW.

.SJT...NONE.

15 N N 

UPPER LOW WAS CURRENTLY OVER THE CENTRAL KS/OK BORDER. SHORTWAVE TROUGH WAS ALSO PUSHING AROUND THE SOUTHERN SIDE OF THE LOW...MOVING INTO SOUTHERN TEXAS. AREA SOUNDINGS...INCLUDING THE ACARS/MAPS SOUNDING FOR IAH...ALL SHOW CAPES NEAR OR EXCEEDING 3000 FOR MUCH OF SETX. WITH THIS IN MIND FEEL THAT THE HIGH POPS FOR THE AREA ARE WARRANTED...INCLUDING THE MENTION OF SEVERE AND HEAVY RAINFALL. STRONG THUNDERSTORMS WERE DEVELOPING JUST WEST OF GRK AT THE MOMENT. THESE STORMS WERE DEVELOPING ALONG A SURFACE TROUGH/OUTFLOW BOUNDARY. SURFACE DEWPOINTS ALONG AND AHEAD OF THE BOUNDARY WERE IN THE MID 60S. ALSO...SOUTHEASTERLY WINDS WERE FEEDING GULF MOISTURE INTO THE DEVELOPING STORMS. A SIDE NOTE...THE HGX VWP WAS SHOWING SOUTHWEST WINDS NEAR THE SURFACE...MORE THAN LIKELY THE RESULT OF MIGRATING BIRDS CONTAMINATING THE ALGORITHM RESULTS.

SO...THE CONCLUSION OF THE MATTER IS THAT ANOTHER ROUND OF THUNDERSTORMS ARE EXPECTED. WILL NOT GO WITH A FLASH FLOOD WATCH AT THIS TIME...THOUGH RAINFALL AMOUNTS COULD REACH 1 INCH OR SO OVER A WIDE AREA. LOCATIONS THAT LOOK TO GET THE HEAVIER RAIN AMOUNTS WILL BE THE FAR NORTHERN COUNTIES OF THE FORECAST AREA.

TEMPERATURES AND WINDS ARE THE MOST DIFFICULT OF THE VARIABLES TO FORECAST TONIGHT. GIVEN THE CURRENT DEWPOINTS FEEL THAT THE FORECAST MINS ARE OKAY. WINDS ARE ANOTHER MATTER. VARIABLE TO SOUTHEAST WINDS SHOULD OCCUR AHEAD OF THE THUNDERSTORMS...WITH NORTH WINDS IN ITS WAKE.

WILL ONLY MAKE MINOR CHANGES TO THE COASTAL FORECAST.

.KHGX...NONE.

PL-40 45



UPDATED ZONES WILL BE OUT SHORTLY TO REFLECT CURRENT PRECIP TRENDS. LOBE ROTATING AROUND MID/UPPER LEVEL LOW PROVIDING JUST ENOUGH LIFT IN MID LEVELS TO SQUEEZE OUT SOME LIGHT RAIN SHOWERS ACROSS THE CNTRL AND SRN TX PNHDL. A FEW LOCATIONS MAY BE ABLE TO RECEIVE MEASURABLE PRECIP AMOUNTS SO WILL INTRODUCE POPS. HOWEVER...THINK MOST LOCATIONS WILL RECEIVE TRACE AMOUNTS.

.AMA... TX...NONE. OK...NONE.

JH



SHOWERS AND THUNDERSTORMS ARE INCREASING IN AREAL COVERAGE AS THE SHORTWAVE OVER FAR WEST TEXAS APPROACHES. ALTHOUGH MOST OF THE SEVERE WEATHER WILL REMAIN JUST SOUTH OF THE FORECAST AREA...A FEW STORMS MAY REACH SEVERE LIMITS ACROSS THE EXTREME SOUTH. THUS HAVE ADDED MENTION OF SEVERE THERE. HAVE ALSO ADJUSTED TONIGHTS LOWS A CATEGORY OR SO ACROSS THE SOUTH AS DEWPOINTS REMAIN IN THE 60S. DRIER AIR SHOULD FILTER IN LATE TONIGHT AS THE WINDS BECOME MORE NORTHERLY.

AVIATION DISCUSSION... HAD TO ADD A MENTION OF TEMPO THUNDERSTORMS BETWEEN 2 AND 4Z FOR THE WACO AREA...THIS MAY HAVE TO BE EXTENDED FOR A COUPLE OF HOURS MORE. THUNDERSTORMS HAVE ALSO FORMED SOUTH OF THE DALLAS/FORT WORTH AREA... THIS ACTIVITY WILL LIKELY REMAIN JUST SOUTH OF THE METROPLEX...SO WILL OPT NOT TO ADD THUNDERSTORSM TO METROPLEX FOR NOW. OTHERWISE.. VFR WILL PREVAIL THIS EVENING ACROSS THE METROPLEX...BUT EXPECT CIGS OF BKN-OVC015 AS WRAP AROUND SLOW MOVING UPPER LEVEL LOW. #58

.FTW...NONE.



THE LATEST KSJT REFLECTIVITY LOOP SHOWS A NARROW BAND OF SHOWERS AND THUNDERSTORMS TRAINING ALONG THE STALLED COLD FRONT WHICH WAS LOCATED ALONG A DFW TO JCT LINE. THE ETA DID SHOW A SHORTWAVE ROTATING INTO OUR SRN ZONES THIS EVENING. THE COMBINATION OF THE SYNOPTIC SCALE FORCING... LOW LEVEL CONVERGENCE ALONG THE BOUNDARY... AND MARGINAL INSTABILITY SHOULD ALL BE ENOUGH TO SUSTAIN THE CONVECTION OVER OUR FAR SERN ZONES FOR A FEW MORE HOURS. AS THE UPPER LOW PUSHES FARTHER SOUTH TONIGHT... EXPECT THE COLD FRONT TO MOVE SLOWLY SOUTH ENDING THE CONVECTIVE THREAT. AS A RESULT... WILL UPDATE ZONES TO INCREASE POPS IN THE ERN HEARTLAND AND NORTHWEST HILL COUNTRY FOR EARLY TONIGHT. IN ADDITION... THE SLOWER MOVING COLD FRONT WILL KEEP TEMPS UP OVERNIGHT IN THIS AREA... SO PLAN TO BUMP LOWS UP A CATAGORY OR TWO.

.SJT...NONE.

TEW N 

SATELLITE IMAGERY INDICATES UPPER LOW CENTERED OVER NORTHWEST OKLAHOMA. WATER VAPOR IMAGERY INDICATES SMALL AMPLITUDE SHORT WAVE OVER EXTREME WEST TEXAS...ROTATING AROUND THE UPPER LOW.

WEAK...NEARLY STATIONARY SURFACE BOUNDARY WAS LOCATED NEAR A AUSTIN...TO LUFKIN LINE. SOME ORGANIZED CONVECTIVE DEVELOPMENT IS EXPECTED OVERNIGHT IN THE VICINITY OF THIS BOUNDARY. EXPECT THE BULK OF THIS ACTIVITY TO AFFECT AREAS EAST AND SOUTH OF THE CWA.

UPPER LOW OVER NORTHWEST OKLAHOMA EXPECTED TO MOVE SLOWLY SOUTHEAST AND WEAKEN THROUGH THE SHORT TERM PERIODS. COLD POOL ASSOCIATED WITH THIS FEATURE SHOULD PROMOTE WIDELY SCATTERED TO SCATTERED...MAINLY DIURNAL TSRA ACROSS CENTRAL AND EASTERN PORTIONS OF THE FORECAST AREA THROUGH WEDNESDAY.

UPPER LEVEL PATTERNS EXPECTED TO BECOME MORE ZONAL ACROSS NORTH AMERICA DURING THE EXTENDED PERIODS. DRY CONDITIONS EXPECTED TO PREVAIL BY THE END OF THE WEEK.

FCSTID = 83 DFW 56 76 57 79 / 10 20 10 10 ACT 56 76 59 80 / 30 30 20 20

.FTW...NONE.

...AVIATION DISCUSSION

VFR TO PREVAIL THIS EVENING BEFORE WRAP AROUND CIGS BKN-OVC015 WRAP AROUND SLOW MOVING UPPER LEVEL LOW. THIS IS A BIT ON THE PESSIMISTIC SIDE AS ETA AND FWC KEEP DRY SLOT OVER N TEXAS TONIGHT. HOWEVER...WET GROUND AND NW WINDS SHOULD ALLOW CIGS TO LOWER AFTER MIDNIGHT. EXPECT THUNDER TO REMAIN SOUTH OF KACT BUT MORE LOW CLOUDS WILL MOVE ACROSS THIS AREA AS WELL. 80



SYNOPSIS... HERE IS THE BORDERLAND WEATHER SYNOPSIS. AN UPPER LEVEL LOW CURRENTLY OVER THE TEXAS PANHANDLE WILL SLOWLY SLIDE SOUTHEAST ACROSS TEXAS AND AWAY FROM THE AREA. THIS WILL ALLOW AN UPPER LEVEL RIDGE TO FORM OVER THE SOUTHWEST. UNDER THE RIDGE TEMPERATURES WILL WARM DAY TO DAY THROUGH THE END OF THE WEEK. BY THURSDAY LOWLAND TEMPERATURES WILL BE BACK IN THE MID 90S. WINDS WILL STAY LIGHT AND SKIES WILL REMAIN RELATIVELY CLOUD FREE.

DISCUSSION... WATER VAPOR SATELLITE IMAGERY SHOWING UPPER LOW SPINNING OVER TX/OK PANHANDLES THIS AFTERNOON. AVN/ETA/NGM IN AGREEMENT IN SAGGING THIS FEATURE SOUTH ACROSS TX. THAT WOULD HELP KEEP TEMPS OVER THE EL PASO FORECAST AREA (FA) SLIGHTLY COOLER AS RIDGE BUILDING OUT WEST IS HELD AT BAY. LOOKING AT H250 WINDS BELIEVE THE LOW WILL PULL OUT SOONER AND TAKE A MORE EASTERN TRACK. STILL, EFFECTS ON FA ARE MINIMAL AS THE WEEK WILL SEE ANOTHER SIGNIFICANT WARMING AS STRONG HIGH PRESSURE BUILDS OVER THE SOUTHWEST ON THE HEELS OF THE EXITING LOW. SHOULD KEEP EAST COMPONENT TO WINDS THIS EVE AND TONIGHT...BUT LIGHT ENOUGH TO ALLOW TEMPS TO BE COOLER THAN SEEN IN SOME WEEKS. WITH HIGH PRESSURE OVER THE AREA AND LOW EXITING...WILL SEE LIGHTER WINDS FOR THE WEEK AND A DRYING OF THE ATMOSPHERE.

IN THE EXTENDED...MRF VERY AGGRESSIVE IN BUILDING A STRONG HIGH OVER THE REGION...OTHER MODELS SUCH AS ECMWF, NOGAPS, AND CANADIAN NOT NEAR AS STRONG...BUT DO BUILD A HIGH...THIS WILL KEEP IT WARM AND DRY.

EL PASO UU 48/ 86/ 54/ 90/ 58 00000 LAS CRUCES UU 44/ 85/ 51/ 89/ 54 00000 ALAMOGORDO UU 42/ 83/ 48/ 87/ 52 00000 CLOUDCROFT UU 25/ 62/ 31/ 66/ 35 00000 TRUTH OR CONSEQUENCES UU 41/ 84/ 47/ 88/ 51 00000 SILVER CITY UU 33/ 75/ 39/ 79/ 43 00000 DEMING UU 42/ 85/ 48/ 89/ 53 00000 LORDSBURG UU 41/ 84/ 48/ 88/ 54 00000 SIERRA BLANCA UU 47/ 84/ 53/ 88/ 56 00000

.ELP...NONE

14 / BIRD

N 

SATELLITE IMAGERY SHOWS AN UPPER LEVEL LOW CHURNING OVER NORTHWEST OKLAHOMA PRESENTLY. THIS UPPER LOW IS EXPECTED TO MOVE SOUTH SOUTHEAST INTO NORTH TEXAS BY TOMORROW AFTERNOON. AN ASSOCIATED 500 MB COLD POOL LOCATED NEAR THE UPPER LOW OVER THE BIG COUNTRY SHOULD ALLOW FOR SOME CU TO FORM ACROSS THE NORTHEAST AND EAST PORTIONS OF THE FORECAST AREA ON TUESDAY. WITH DAYTIME HEATING...I WOULD NOT RULE OUT A SHOWER FOR THIS AREA.

THE UPPER LOW WILL GRADUALLY SLIDE EAST OF THE AREA...WITH ASSOCIATED SFC LOW PRESSURE ALSO MOVING EAST OF THE AREA BY WEDNESDAY MORNING. SFC LEE TROFFING WILL SET UP BY WEDNESDAY WITH SOUTHEAST SFC WINDS FORECAST EAST OF THE MOUNTAINS ALONG WITH INCREASING LOW LEVEL MOISTURE. THIS WILL LEAD TO WARMER NIGHTTIME TEMPERATURES. IN FACT...A GENERAL WARMING TREND IS EXPECTED INTO THE EXTENDED PERIOD AS AN UPPER LVL RIDGE INTENSIFIES OVER THE WEST TEXAS AND NEW MEXICO.

PRELIMINARY CCF...

MAF 48/75/52/84 0000 LSA 46/74/50/83 0110 E41 49/76/55/81 0210 6R6 54/78/59/87 0--0 MRF 42/76/45/83 0000 CNM 47/77/49/89 0000

.MAF... TX...NONE. NM...NONE.

VESPER/03



SATELLITE IMAGERY INDICATES UPPER LOW CENTERED OVER NORTHWEST OKLAHOMA. WATER VAPOR IMAGERY INDICATES SMALL AMPLITUDE SHORT WAVE OVER EXTREME WEST TEXAS...ROTATING AROUND THE UPPER LOW.

WEAK...NEARLY STATIONARY SURFACE BOUNDARY WAS LOCATED NEAR A AUSTIN...TO LUFKIN LINE. SOME ORGANIZED CONVECTIVE DEVELOPMENT IS EXPECTED OVERNIGHT IN THE VICINITY OF THIS BOUNDARY. EXPECT THE BULK OF THIS ACTIVITY TO AFFECT AREAS EAST AND SOUTH OF THE CWA.

UPPER LOW OVER NORTHWEST OKLAHOMA EXPECTED TO MOVE SLOWLY SOUTHEAST AND WEAKEN THROUGH THE SHORT TERM PERIODS. COLD POOL ASSOCIATED WITH THIS FEATURE SHOULD PROMOTE WIDELY SCATTERED TO SCATTERED...MAINLY DIURNAL TSRA ACROSS CENTRAL AND EASTERN PORTIONS OF THE FORECAST AREA THROUGH WEDNESDAY.

UPPER LEVEL PATTERNS EXPECTED TO BECOME MORE ZONAL ACROSS NORTH AMERICA DURING THE EXTENDED PERIODS. DRY CONDITIONS EXPECTED TO PREVAIL BY THE END OF THE WEEK.

FCSTID = 83 DFW 56 76 57 79 / 10 20 10 10 ACT 56 76 59 80 / 30 30 20 20

.FTW...NONE.



THE 17Z WATER VAPOR SATELLITE IMAGERY SHOWS AN UPPER LEVEL LOW CENTERED OVER THE OK PANHANDLE. AN UPPER LEVEL RIDGE WAS LOCATED OVER THE WESTERN HALF OF THE CONUS...WHILE AN UPSTREAM TROUGH WAS AMPLIFYING OVER THE EASTERN PACIFIC. AN UPPER LEVEL SHORTWAVE TROUGH WAS DIGGING SOUTHEAST ACROSS THE UPPER GREAT LAKES.

THE 17Z SURFACE OBSERVATIONS SHOW A WEAK SURFACE LOW OVER WESTERN MISSOURI WITH A TRAILING COLD FRONT EXTENDING SOUTH-SOUTHWEST ACROSS CENTRAL OK INTO CENTRAL TX.

THIS AFTERNOON...SKIES WERE MOSTLY SUNNY OVER THE SOUTHWESTERN SECTIONS OF THE FORECAST AREA AND MOSTLY CLOUDY OVER THE NORTHEAST SECTIONS. THE LOW AND MID-LEVEL CLOUDS ROTATING AROUND THE UPPER LOW OVER EASTERN NM HAVE BEEN DISSIPATING AS THEY MOVE SOUTHEAST ONTO THE LOWER TERRAIN DUE TO SUBSIDENCE...AS THE AIR PARCELS MOVE EAST FROM HIGHER TO LOWER TERRAIN. WITH A POCKET OF COLD AIR ALOFT IN THE VICINITY OF THE UPPER LEVEL LOW...AFTERNOON HEATING ALONG WITH RESIDUAL MOISTURE WILL CAUSE CUMULUS CLOUDS TO DEVELOP ACROSS THE FORECAST AREA. IF ENOUGH CAPE IS AVAILABLE...PERHAPS AN EVENING SHOWER OR THUNDERSTORM MAY DEVELOP. THE BEST CHANCE FOR LATE AFTERNOON AND EVENING SHOWERS OR THUNDERSTORMS WILL OCCUR OVER THE NORTH-CENTRAL AND NORTHEAST SECTION OF THE FORECAST AREA CLOSER TO THE UPPER LEVEL LOW WHERE 500MB TEMPERATURES WILL RANGE FROM -17 T0 -19 DEGREES...ALSO THERE WILL BE LESS SUBSIDENCE. AT THIS TIME I WILL CARRY A SLIGHT CHANCE OF SHOWERS OR THUNDERSTORMS ACROSS THE NORTH-CENTRAL AND EASTERN SECTIONS OF THE FORECAST AND KEEP SKIES PARTLY CLOUDY TONIGHT. IF BY ZONE ISSUANCE THE CU FIELD DOESN'T SHOW MUCH VERTICAL GROWTH I MAY PULL THE SLIGHT CHANCE FOR A SHOWER OR THUNDERSTORM THIS EVENING. OVER THE SOUTH-CENTRAL AND WESTERN SECTIONS OF THE FORECAST AREA I WILL GO WITH MOSTLY CLEAR SKIES AS THE DOWNGLIDE SHOULD DISSIPATE THE LOW CLOUDS. THERE MAY BE A FEW PASSING HIGH AND MID-LEVEL CLOUDS. ANY CUMULUS CLOUDS AND SHOWERS THAT DO FORM ACROSS THE FORECAST AREA WILL DISSIPATE AFTER SUNSET.

THE ETA MODEL SHOWS THE UPPER LEVEL LOW DIGGING SOUTHEAST INTO WESTERN OK DURING THE DAY TUESDAY. THE RIDGE AXIS OVER THE WESTERN US WILL BUILD NORTHEAST OVER THE CENTRAL PLAINS. THE UPPER LEVEL CLOSED LOW OVER OK WILL BE CUT OFF FROM THE WESTERLY ZONAL FLOW FORMING A MINOR REX BLOCK. 500-1000 MB THICKNESSES WILL INCREASE TOMORROW AFTERNOON ALLOWING TEMPERATURES TO WARM INTO THE 70S ACROSS THE FORECAST AREA. THERE MAY BE A SLIGHT CHANCE OF AN AFTERNOON SHOWER OR THUNDERSTORM TUESDAY AFTERNOON OVER THE EASTERN SECTIONS OF THE FORECAST AREA SINCE THE WESTERN EDGE OF THE MID-LEVEL COLD POOL WILL BE OVER THE EASTERN COUNTIES. I WILL STICK A 20 POP IN THE EASTERN COUNTIES OF THE FORECAST AREA FOR TUESDAY AFTERNOON. BY 48 HOURS THE ETA MODEL FORECAST THE UPPER LEVEL CLOSED LOW TO MOVE SOUTHEAST INTO EASTERN TX AND FILL. AFTERNOON HIGHS WILL WARM INTO THE 80S ON WEDNESDAY AS THE 500-1000MB THICKNESSES INCREASE AND THE UPPER LEVEL RIDGE AXIS MOVES CLOSER TO THE REGION.

EXTENDED OUT LOOK: THE MRF...ECMWF AND CANADIAN MODEL SOLUTIONS ARE SIMILAR KEEPING THE UPPER LEVEL JET STREAM OVER THE NORTHERN US AND SOUTHERN CANADA WITH THE RIDGE AXIS AMPLIFYING OVER THE CENTRAL CONUS. EXPECT DRY AND WARM CONDITIONS TO CONTINUE THROUGH THE END OF THE WEEK.

FRIONA 42/74/46/82 1-00 LUBBOCK 44/74/47/83 --00 TULIA 43/72/46/82 11-0 BROWNFIELD 44/76/47/85 --00 CHILDRESS 46/70/50/80 1210 ASPERMONT 49/72/52/82 1210

.LBB...NONE.

20



UPPER LOW NEAR THE TEXAS PANHANDLE-WESTERN OKLAHOMA BORDER WILL WEAKEN AND SLOWLY DRIFT TOWARD SOUTHEAST TEXAS THROUGH THURSDAY. ENERGY ROTATING AROUND THE LOW WILL IGNITE SHOWERS AND THUNDERSTORMS LATER THIS AFTERNOON AND TONIGHT TO OUR WEST AND SOUTHWEST. ACTIVITY WILL ORGANIZE INTO ANOTHER MCS AND DRIFT TO THE SOUTHEAST AND EAST OVERNIGHT. MODELS INDICATE GOOD UVM VALUES...HIGH MOISTURE LEVELS (PW VALUES 1.50 TO 1.75 INCHES)...AND A FOCUSING BOUNDARY (OLD OUTFLOWS AND FRONTAL BOUNDARY OVER SOUTH CENTRAL TEXAS) IN THE AREA. STILL UNCERTAIN AS TO WHICH EXACT ROUTE THE MCS WILL TAKE...BUT SOME IF NOT ALL OF OUR AREA HAS A GOOD SHOT OF SEEING MORE STORMS TONIGHT AND TOMORROW MORNING. CANNOT RULE OUT THE THREAT FOR SOME HAIL AND STRONG WINDS WITH THE STRONGER STORMS SO WILL INCLUDE THE MENTION OF SEVERE IN THE FIRST PERIOD. WILL ALSO MENTION LOCALLY HEAVY RAIN THREAT FOR BOTH TONIGHT AND EARLY TOMORROW MORNING. EXPECT MOST AREAS TO SEE UP TO AN INCH OF RAIN WITH ISOLATED SPOTS POSSIBLY GETTING 3 TO 4 INCHES. WILL HOLD OFF ON A FLASH FLOOD WATCH SINCE RAINS FROM EARLIER TODAY HAVE HAD TIME TO RECEDE/DISSIPATE. WOULD PREFER TO SEE WHERE THE MCS DEVELOPS BEFORE JUMPING ON A WATCH.

AS THE UPPER LOW CONTINUES TO HEAD THIS WAY...EXPECT A BREAK FROM THE STORMS TOMORROW AFTERNOON THEN ANOTHER SHOT TUESDAY NIGHT/ WEDNESDAY MORNING. THERE'S A CHANCE WE COULD HAVE THIS ON-AGAIN/ OFF-AGAIN TYPE OF SHOWERS AND THUNDERSTORMS THROUGH THE REST OF THE WEEK AS THE MEDIUM RANGE MODELS KEEP THE UPPER LOW IN OUR VICINITY. WILL KEEP A CHANCE OF RAIN THROUGH THE EXTENDED FORECAST. PRELIMS ARE NEXT.

.KHGX...NONE.

42/37/35

PRELIMS... CLL TT 063/077 062/080 064 42766 IAH TT 066/078 065/081 065 42766 GLS TT 072/078 070/079 070 42766



MAIN STORY TONIGHT WILL BE THE TRACK OF MID/UPPER LEVEL LOW CURRENTLY LOCATED BETWEEN WICHITA KANSAS AND GAGE OKLAHOMA. MODELS TRACK LOW CENTER TOWARDS THE RED RIVER AREA BY 12Z TUESDAY AND THEN OVER NORTHEAST TEXAS TUESDAY AFTERNOON. 12Z AVN A BIT MORE PROGRESSIVE NEAR LAWTON OK COMPARED TO THE SLOWER NGM NEAR ALTUS BUT DECENT AGREEMENT NONETHELESS. STILL EXPECT SOME WRAP AROUND ENERGY TO BRUSH THE EASTERN ZONES TONIGHT BEFORE PRECIP ENDS BY TUESDAY AFTERNOON. REFLECTIVITY IMAGERY INDICATES SOME LIGHT RETURNS OVER PORTIONS EASTERN ZONES. PLAN TO HOLD ON TO LOW CHANCE POPS OUT EAST TONIGHT WITH A DRY FORECAST OVER WESTERN ZONES.

12Z MODELS ALSO INDICATE ISENTROPIC DOWNGLIDE ALONG THE 295 K SURFACE BY 12Z TUESDAY SO WOULD NOT EXPECT MUCH IN THE WAY OF FOG DEVELOPMENT AFTER MIDNIGHT. NORTH WINDS TONIGHT MAY BECOME LIGHT AND VARIABLE TOWARDS SUNRISE AS SURFACE HIGH SETTLES OVER THE PANHANDLES. SURFACE HIGH WILL SLIDE EAST OF THE AREA TUESDAY NIGHT AS LEE TROF REDEVELOPS OVER EASTERN COLORADO. WAA PATTERN AND LOW LEVEL JET SHOULD BECOME REESTABLISHED OVER THE SOUTHERN HIGH PLAINS WEDNESDAY AND ESPECIALLY WEDNESDAY NIGHT.

EXTENDED...SEVERE WEATHER ON SATURDAY SEEMS TO BE A REOCCURING THEME FOR THE PANHANDLES DURING THE PAST 4 SATURDAYS. LATEST MRF KEEPS THIS STRING OF STORMY SATURDAYS GOING. A NORTHERN STREAM SHORTWAVE WILL DISLODGE ANOTHER COLD FRONT INTO THE SOUTHERN PLAINS SATURDAY NIGHT WHILE MOST OF THE UPPER ENERGY REMAINS NORTH OF THE PANHANDLES. HOWEVER...MOIST THERMAL ADVECTION PATTERN ASSOCIATED WITH THE LOW LEVEL JET WILL BE WELL ESTABLISHED BY THURSDAY. AIRMASS OVER THE REGION SHOULD BE WELL PRIMED WHEN FRONT REACHES THIS AREA BUT EXPECT CAP TO BE FAIRLY STRONG UNDER THE WARM RIDGE. WILL INTRODUCE CHANCE POPS SATURDAY OVER EASTERN ZONES WITH SLIGHT CHANCE WESTERN ZONES WHICH MAY BE WEST OF THE DRYLINE. STAY TUNED FOR MORE INFO.

PRELIM... AMA 40/70 49/80 55 -00 DHT 40/72 47/82 53 000

.AMA... TX...NONE. OK...NONE.

SLATTERY



LATEST WATER VAPOR IMAGERY SHOWS AN UPPER LOW SPINNING SLOWLY SOUTHWARD ACROSS THE SOUTHEASTERN TEXAS PANHANDLE TOWARD NORTH CENTRAL TEXAS. AT THE SURFACE....COLD FRONT HAS PUSHED SOUTH OF THE AREA AND WAS LOCATED FROM NEAR COLLEGE STATION TO EAST OF AUSTIN NEAR LAREDO. A LINE OF WEAK SHOWERS AND THUNDERSTORMS HAS LINGERED ACROSS SOUTHERN KIMBLE AND MASON COUNTIES ALL DAY TODAY AND MAY CONTINUE FOR A COUPLE HOURS THIS EVENING.

FOR THE MOST OF THE AREA...FORECAST SHOULD BE DRY FOR THIS EVENING WITH SATELLITE SOUNDINGS SHOWING A STABLE AIRMASS ACROSS ALL BUT THE FAR SOUTHEAST. WITH LINGERING SHOWERS OVER THE NORTHWEST HILL COUNTRY...WILL CONTINUE SLIGHT CHANCE POPS FOR THIS EVENING. MODELS ALL BRING UPPER LOW VERY SLOWLY SOUTHEASTWARD...WITH LOW CENTERED JUST EAST OF ABILENE BY TOMORROW AFTERNOON AND SOUTH OF DALLAS FT WORTH BY WEDNESDAY AFTERNOON. AT THE SURFACE...HIGH PRESSURE WILL BUILD IN ACROSS THE NORTHERN HALF OF WEST CENTRAL TEXAS TONIGHT AND CONTINUE TO REMAIN IN CONTROL THROUGH EARLY WEDNESDAY. DESPITE THE UPPER LOW IN THE AREA...RELATIVELY DRY AIRMASS AND LACK OF BOUNDARIES SHOULD LEAD TO A GENERALLY DRY FORECAST FOR TUESDAY AND WEDNESDAY. AM STILL A LITTLE CONCERNED ABOUT EASTERN COUNTIES WITH REMNANT OUTFLOW BOUNDARIES FROM PREVIOUS STORMS AND VICINITY OF COLD UPPER LOW...SO WILL CONTINUE SLIGHT CHANCE PRECIP FOR THAT AREA. OTHERWISE...SHOULD SEE ONE MORE DAY OF SLIGHTLY BELOW NORMAL TEMPERATURES FOR TUESDAY WITH A WARMUP BEGINNING ON WEDNESDAY. LEE TROUGH BEGINNING TO TAKE SHAPE WEDNESDAY AFTERNOON WILL BRING A RETURN OF SOUTHEASTERLY WINDS TO THE AREA.

IN THE EXTENDED...UPPER LOW LINGERS NEAR SOUTHEAST TEXAS COAST THROUGH SATURDAY. DRYLINE OVER FAR WEST TEXAS TRIES TO MOVE INTO THE AREA FRIDAY AND SATURDAY AFTERNOON. WITH MOISTURE BACK ACROSS THE AREA AND WEAK UPPER LOW STILL IN THE NEIGHBORHOOD...CAN NOT RULE OUT A FEW STORMS ALONG THE DRYLINE FOR THE END OF THE WEEK. WILL CONTINUE WITH SLIGHT CHANCE POPS IN THE EXTENDED.

PRELIMS... ABI 051/075/055/083 0-11 SJT 050/077/054/085 0-11 JCT 051/077/054/086 2-21

.SJT...NONE. 08 N 

INTERESTING 24 TO 36 HOURS COMING UP. AS EXPECTED...ENVIRONMENT IS STILL IN STATE OF RE-ADJUSTMENT AFTER MCS MOVED TO EAST JUST NORTH OF CWFA. GOOD OUTFLOW MOVED THROUGH CWFA THIS MORNING BRINGING GUSTY EAST WINDS AND DROPPING DWPTS INTO MID 60S. NEXT SHORT WAVE TROUGH IS BACK NEAR ELP PER WV LOOP AND THIS SHOULD BRING CONVECTION FURTHER SOUTH IN THIS ROUND. FRONT IS DIFFICULT TO FIND BUT APPEARS TO BE JUST NORTH OF SAT TO JUST SOUTH OF DRT. CONVECTION IS ALREADY STARTING TO REFIRE IN THIS AREA. MODELS SOLNS ARE FAIRLY CLOSE WITH BULLEYES IN VERTICAL MOTION AND DIVERGENCE FIELDS BY MIDNIGHT TONIGHT. NGM IS HAVING SFC FEATURE PROBLEMS AND WILL NOT USE. WITH 500 HPA LOW FCST TO REMAIN OVER TX...BUT DRIFT SOUTHEAST...WILL LEAVE CLOUDS AND PRECIP IN FCST THROUGH WEDNESDAY NIGHT. WILL TREND TEMPS DOWN NEXT FEW DAYS DUE TO RAIN COOLED AIR. GUIDANCE TEMPS REALLY NOT OF MUCH USE DUE TO CONVECTION. WILL ISSUE SPS FOR POTENTIAL HEAVY RAIN TONIGHT. NOT AN ENORMOUS AMOUNT OF COOLING AT 500 HPA...SO SEVERE THREAT IS APPEARS LIMITED TO LOCALIZED WIND EVENTS.

EXTENDED...MRF APPEARS TO BE BACKING OFF FROM YESTERDAY'S UNREALISTIC SOLN OF RETROGRADING THE CLOSED LOW OVER TX INTO MEXICO. IT HAS COME AROUND TO A GRADUAL EASTWARD DRIFT TO THE 500 HPA LOW. THIS SHOULD SHUTDOWN PRECIP CHANCES IN EXTENDED PERIOD...SO WILL MAINTAIN A DRY EXTENDED FOR NOW.

MARINE...WILL MAINTAIN SCA FOR TONIGHT AS 30KT LLJ WILL REMAIN OVER AREA. WIND SPEEDS WILL DECREASE TO BELOW SCA AROUND 12Z...AS LLJ MOVES OUT OF AREA...AND COLD FRONT APPROACHES AND BECOMES STATIONARY. WILL KEEP POPS IN THRU WED...BUT ONLY ISOLATED ON TUES NIGHT AND WED AS FRONTOLYSIS OCCURS AND FLOW REMAINS ONSHORE. WW3 WAVE HGTS ARE A BIT LOW AND WILL KEEP SEAS AT 8 FEET TONIGHT AND SUBSIDE THEM BY TUE NIGHT.

PRELIMS... CRP TE 067/079 067/082 068 663 VCT TE 064/077 065/082 068 773 LRD TE 067/080 066/085 065 643

.CRP...SCA GMZ230-250-255-270-275.

78/91/75



SATELLITE PIC HAS AMPLY MID AND HIGH CLOUDS AND MOISTURE CONTINUING FROM THE WEST OVER THE CWA. RAIN AND CONVECTIVE ACTIVITY OCCURRING WITH THE MCS LAST NIGHT AND THIS MORNING HAVE MOVED NORTHEAST. HIGH PRESSURE RIDGE OVER COLORADO IS SLIDING SOUTHEAST...LOW PRESSURE OVER EASTERN OKLAHOMA/ARKANSAS MOVING NORTHEAST...FRONT OVER HILL COUNTY BEGINNING TO SLOWLY SLID EASTWARD THROUGH REMAINING CWA. ALL THIS LEADS ME TO BELIEVE THAT CONVECTIVE ACTIVITY WILL CONTINUE OVER THE CWA THROUGH TONIGHT AND INTO TUESDAY AS A OVER-RUNNING CONDITIONS PREVAILS...HOWEVER BRIEF AND ISOLATED IT MAY BE.

FRONT NOT MOVING FAST ENOUGH TO CLEAR THE CWA BEFORE TONIGHT AS GULF HIGH DEW-POINTS VALUES INFLOW CONTINUES TO SLIDE NORTH UP OVER HILL COUNTRY COUNTIES AND PORTIONS OF SOUTH CENTRAL SECTIONS. ISOLATED CONVECTIVE ACTIVITY CONTINUES TO FIRER ALONG BOUNDARIES CREATED FROM THE EARLIER ACTIVITY.

EXPECT CONVECTIVE ACTIVITY TO INCREASE TONIGHT. SURFACE DEW-POINT DRIER IN THE WESTERN COUNTIES BUT STILL REMAIN IN THE 60S OVER THE EASTERN SECTIONS.

WILL KEEP ISOLATED BRIEF LOCALLY HEAVY RAIN AND SEVERE WEATHER THREAT FOR TONIGHT'S FORECAST. AS SPC STILL HAS SEVERE MENTION FOR ENTIRE CWA MONDAY NIGHT.

EXTENDED FORECAST...WEDNESDAY THROUGH FRIDAY STILL HAS CWA UNDER MOSTLY CLOUDY SKIES...20 TO 30 PERCENT POPS.

PRELIMINARY NUMBERS...

DRT 62/81/62/85 3222 AUS 61/74/61/80 4332 SAT 60/76/62/82 4322

.EWX...NONE.



DO NOT PLAN TO CHANGE FORECAST MUCH. STORM CHANCES HERE APPEAR SIGNIFICANT AS UPPER LOW IN OKLAHOMA MEANDERS SOUTHEAST THE NEXT SEVERAL DAYS. LOW HAS A CONVECTIVE HISTORY. FOR A PERIOD...BACK SIDE OF THE LOW WILL BE UNSTABLE BEFORE AIR SUBSIDES AND DRIES WEST OF THE LOW. BEST CHANCES FOR RAIN HERE SEEM TO BE TONIGHT AND TOMORROW AS LOW LEVEL GULF AIR FEEDS THE MONSTER ALOFT NEARBY BEFORE CONVERGENT AREA SHIFTS NORTHEAST TOMORROW AFTERNOOON.

WILL LOWER MARINE FLAGS AS GRADIENT CONTINUES TO WEAKEN.

BRO TB 073/086 070/084 070 62553 MFE TB 072/088 071/088 070 62553 RGC TB 070/089 066/089 067 62553 SPI TB 076/082 075/082 076 62553

.WFO BRO INTERNET ADDRESS... WWW.SRH.NOAA.GOV/BRO

.BRO...NONE.



AVIATION DISCUSSION...EXPECT SOME CLEARING OF MVFR CEILINGS ACROSS THE DFW SITES BEFORE 21Z...PER SATELLITE IMAGERY AND LATEST RUC OUTPUT. EXPECT WEST-NORTHWEST WIND TO PREVAIL THROUGH 12Z. PRECIPITATION CHANCES TOO LOW TO WARRANT MENTION IN TAF.

COORD. WITH CWSU ZFW.

83

1110 AM CDT MON MAY 01 2000

UPDATED ZONES TO DROP SEVERE AND HEAVY RAIN THREAT AND ALSO MAKE CHANGES TO POPS AND WINDS.

.FTW...NONE

59



BASICALLY JUST UPDATED WRN AND SRN SXNS TO LWR POPS THIS AFTN. SOME SHRA/S MOVG SWD OUT OF THE CNTRL OK PNHDL INTO THE N-CNTRL TX PNHDL...BUT THESE ARE WKNG AND DSIPTG AS THEY CONT MOVG SWD THRU THE CNTRL TX PNHDL. KEPT POPS ALONE ACRS THE N-CNTRL AND NERN SXNS OF THE FA. ALSO...BUMPED UP WNDS EVERYWHERE INTO CAUTION CRITERIA OF 15-25 MPH RANGE. UPR LOW LOCATED W OF KP28 AND S OF KDDC IN SWRN KS ATTM WHICH IS FCSTD TO DIG SWD TDA INTO NWRN OK. PRES GRAD TIGHT ACRS THE PNHDLS AS SFC RDG BUILDS DOWN INTO THE FA AND CAA CONTS. OTRW...NO OTR CHGS TO PREV FCST.

.AMA... TX...NONE. OK...NONE.

SCHNEIDER



NO UPDATES NEEDED SO FAR BUT WILL MONITOR WEST CENTRAL AND BOI MTNS FOR CONTINUED SHOWERS UNDER UPR TROF PASSAGE. MODIFIED 12Z BOI/MFR SOUNDINGS AND ETA FORECAST 00ZMAY3 SOUNDINGS SHOW STEEP LAPSE RATES WITH 300-600 CAPE AND -2/-3 LIS BUT WITH LITTLE MID LEVEL MOISTURE. UPPER AIR TROF PASSAGE EXPECTED LATE MORNING-AFTERNOON AND PRES RISES BEHIND FRONT OVER SW ID SHIFTING THRU TWF AREA EARLY THIS AFTN FOR GUSTY BREEZY WINDS THERE. FSL ACARS SOUNDING NEAR BOI AND MODIFIED MFR SOUNDING SHOWS DEVELOPING CAP ABOUT 700 MBS...-1.6C BOI RAOB TO -2.5C MFR RAOB AND SLC-BOI DESCENT/COR/ FLIGHT...LIMITING CHCS OF TSTMS IN SPITE OF DECENT INSTABILITY AND LIFTING TRIGGER. MORE MOISTURE IN ID MTNS BUT BECOMING CAPPED. TEMPS RSNBL AS SPRING SUNSHINE GIVES DIURNAL RANGES ABOUT 20F.

.BOI...NONE.



SHORTWAVE CURRENTLY IN CENTRAL ID PRODUCING VERY LITTLE SHOWER ACTIVITY. ISOLD LIGHT SHOWERS DEPICTED ON 88D OVER CENTRAL ID MTN ZONES. WAVE ON TRACK TO LIFT NORTHEAST DURING THE DAY...WITH SOME CLEARING EXPECTED ALONG ITS BACK EDGE. TRAILING WEAK COOL FRONT WILL MOVE ACROSS CWA TODAY. WINDS PICKING UP ALREADY ALONG UPPER SNAKE PLAINS ALONG SOUTHERN HIGHLANDS (PIH...FOR EXAMPLE). THESE WINDS WILL CONTINUE TO INCREASE FURTHER NORTH EXTENDING TO UPPER SNAKE PLAINS BY THE AFTERNOON. TEMPS DOWN A FEW DEGREES TODAY WITH LOWER THICKNESSES. WILL BUMP UP WINDS IN VALLEY ZONES AND SHOW A DECREASING CLOUD TREND. OTHERWISE...ZONES LOOK GOOD. WAW BYI 77/45/82 000

.KSFX 88D...OPERATIONAL...VCP 32.

.PIH...NONE

PIH BB 075/040 080/047 076 08000



SURFACE THERMAL PRESSURE TROUGH HAS ALREADY MOVED EAST OF OUR CWA NOW CENTERED WESTERN MONTANA AND EASTERN IDAHO. WINDS NOW SOUTHWEST TO NORTHWEST EVERYWHERE AND INCREASING AS COOLER AIR SPREADS IN AT ALL LEVELS. UPPER LEVEL SHORTWAVE TROUGH ALREADY WEAK AND CONTINUES TO LOSE AMPLITUDE AS IT DISTANCES ITSELF FROM THE MAIN UPPER LOW WHICH CONTINUES TO SPIN OFF THE QUEEN CHARLOTTE ISLANDS. MOISTURE AND DYNAMICS CONCENTRATED NORTH OF OUR CWA WITH 88D SHOWING ONLY A NARROW BAND OF LIGHT PRECIP OVER SOUTHEAST OREGON AT THIS TIME. WILL KEEP LOW POPS FOR THIS MORNING EASTERN OREGON ZONES AND WEST CENTRAL IDAHO MOUNTAINS. MINOR SHORTWAVE RIDGING WITH SOME SUBSIDENCE THIS AFTERNOON THROUGH EARLY WEDNESDAY. NEXT SHORTWAVE CURRENTLY APPROACHING 130W SHOULD WEAKEN ALSO AS IT DRIFTS EAST. WILL MENTION CHANCE POPS WITH THIS ONE FOR WEDNESDAY AFTERNOON AGAIN FOR AREAS WEST AND NORTH OF BOISE. TEMPERATURES ONLY ABOUT 5-8 DEGREES COOLER THAN YESTERDAY THEN SLIGHT RECOVERY FOR WEDNESDAY. MODEL SOUNDINGS SHOW IT NEVER GETS UNSTABLE ENOUGH FOR MORE THAN SLIGHT CHANCE THUNDER WEDNESDAY AFTERNOON.

CONTINUED ONSLAUGHT OF SHORTWAVES WILL LOWER THE HEIGHTS AND PUSH THE BAROCLINIC ZONE FARTHER SOUTH THURSDAY AND FRIDAY. WILL NEED TO MENTION CHANCE SHOWERS EVEN SOUTHERN ZONES THOSE TWO DAYS BEFORE HEIGHTS BEGIN TO REBOUND ON SATURDAY. /JT

.BOI...NONE.



H3 120KT JET STREAMING ALONG 40N WITH ON SHORE SPLITTING FLOW VICINITY OF NORTHERN CALIFORNIA AND FORECAST AREA UNDER INFLUENCE OF NORTHERN BRANCH OF FLOW. FIRST OF SEVERAL EMBEDDED SHORT WAVES MOVING THROUGH CENTRAL OREGON AND WASHINGTON THIS MORNING. MOST MOISTURE AND SHOWERS SHEARS TO THE NORTHEAST ACROSS PAN HANDLE. CURRENT RADAR AND SATELLITE IMAGERY INDICATE SAWTOOTH MOUNTAINS SHOULD BE ON SOUTHERN FRINGE OF SHOWERS...AND POSSIBLY THE UPPER SNAKE HIGHLANDS LATER THIS AFTERNOON. THEREFORE WILL CONTINUE ISOLATED SHOWERS IN THESE AREAS.

ASSOCIATED SURFACE LOW AND COOL FRONT VICINITY OF SOUTHWEST IDAHO BORDER AT 06Z...SHOULD REACH THE UPPER SNAKE RIVER VALLEY 16 TO 18Z... GRADUALLY STRETCHING EAST WEST THROUGH THE UPPER END OF THE VALLEY THIS AFTERNOON. EXPECT VALLEY WINDS 15 TO 25 MPH BY LATE MORNING.

MINOR SHORT WAVE WEDNESDAY PASSES FURTHER NORTH WITH GULF OF ALASKA LOW ROTATING INTO BRITISH COLUMBIA COAST WITH INCREASED RIDGING OVER FORECAST AREA.

AVN ROTATES NEXT SPOKE OF ENERGY AROUND GULF LOW THURSDAY WITH SHORT WAVE ENERGY TAKING A BIT FURTHER SOUTH BITE INTO IDAHO FOR CHANCE POPS MOST AREAS. PROXIMITY OF H3 JET WITH RIGHT ENTRANCE REGION OFFERS MORE SUPPORT FOR SHOWERS. ALSO VALLEY WINDS MORE WINDY AND WILL ADD THIS TO EXTENDED FORECAST. 00Z MRF BRINGS NEXT SHORT WAVE INTO MEAN EASTERN PACIFIC TROUGH BY SATURDAY WHICH HELPS BUILD RIDGE OVER SOUTHEAST IDAHO FOR ANOTHER DRY AND WARM PERIOD GOING INTO THE WEEKEND. SURVICK BYI 77/45/82 000

.KSFX 88D...OPERATIONAL...VCP 32.

.PIH...NONE

PIH BB 075/040 080/047 076 08000



SURFACE THERMAL PRESSURE TROUGH IN SOUTHWEST IDAHO AND MOVING EAST AS A COLD FRONT IN CENTRAL WASH/ORE PUSHES EAST. REGIONAL RADAR INDICATES ISOLATED SHOWERS HAVE MOVED INTO EASTERN OREGON. LARGER AREA OF SHOWERS HAS JUST CROSSED THE CASCADES AS OF 9 PM MDT. SATELLITE AND RADAR LOOPING INDICATES THESE SHOWERS HAVE DECREASED IN INTENSITY WITH THEIR EASTWARD PROGRESS. HOWEVER...SIZE OF AREA SUGGESTS POPS NEED TO BE A BIT HIGHER FOR SOUTHEAST OREGON ZONES...WILL MAKE THIS SO. WILL DO THE SAME FOR WEST CENTRAL MOUNTAINS ZONES. STILL EXPECT THE FRONT INTO THE BOISE AREA A LITTLE AFTER MIDNIGHT. HOWEVER WINDS SHOULD SHIFT TO THE WEST BEFORE THEN WITH THERMAL TROUGH MOVEMENT. WILL MAKE MINOR ADJUSTMENT TO WINDS TOO. NO OTHER SIGNIFICANT CHANGES TO CURRENT FORECAST. COOLER AND DRIER ON TUESDAY.

.BOI...NONE.

EGGER



SLOW ERODING OF THE UPPER TROUGH OVER IDAHO. ONE SHORT WAVE PASSING OVER TONIGHT WITH MAIN MOISTURE TO THE SOUTH AND JUST SOME MID AND HIGH LEVEL CLOUDS PASSING OVER SOUTHERN IDAHO. NEXT SHORT WAVE JUST ON THE OREGON-WASHINGTON COAST HAS MORE MOISTURE ASSOCIATED AND WILL BRING A CHANCE OF SHOWERS TO THE CENTRAL MOUNTAINS TUESDAY. SOUTHWEST FLOW PERSISTS ALOFT AS THE GULF OF ALASKA LOW REMAINS ANCHORED IN...THE GULF OF ALASKA. THE GENERAL WEATHER THROUGH THE EXTENDED PERIOD REMAINING WARMER THAN NORMAL WITH OCCASIONAL SHORT WAVES RIPPELING THROUGH ON THE SOUTHWEST H5 FLOW. WILL UPDATE 1ST PERIOD FOR INCREASED CLOUDS TONIGHT. OTHERWISE FORECASTS LOOK GOOD. BYI 49/77 45/79 000

.KSFX 88D...OPERATIONAL...VCP 32.

.PIH...NONE

PIH BB 044/076 042/078 044 04000



UPPER LOW WAS CURRENTLY OVER THE CENTRAL KS/OK BORDER. SHORTWAVE TROUGH WAS ALSO PUSHING AROUND THE SOUTHERN SIDE OF THE LOW...MOVING INTO SOUTHERN TEXAS. AREA SOUNDINGS...INCLUDING THE ACARS/MAPS SOUNDING FOR IAH...ALL SHOW CAPES NEAR OR EXCEEDING 3000 FOR MUCH OF SETX. WITH THIS IN MIND FEEL THAT THE HIGH POPS FOR THE AREA ARE WARRANTED...INCLUDING THE MENTION OF SEVERE AND HEAVY RAINFALL. STRONG THUNDERSTORMS WERE DEVELOPING JUST WEST OF GRK AT THE MOMENT. THESE STORMS WERE DEVELOPING ALONG A SURFACE TROUGH/OUTFLOW BOUNDARY. SURFACE DEWPOINTS ALONG AND AHEAD OF THE BOUNDARY WERE IN THE MID 60S. ALSO...SOUTHEASTERLY WINDS WERE FEEDING GULF MOISTURE INTO THE DEVELOPING STORMS. A SIDE NOTE...THE HGX VWP WAS SHOWING SOUTHWEST WINDS NEAR THE SURFACE...MORE THAN LIKELY THE RESULT OF MIGRATING BIRDS CONTAMINATING THE ALGORITHM RESULTS.

SO...THE CONCLUSION OF THE MATTER IS THAT ANOTHER ROUND OF THUNDERSTORMS ARE EXPECTED. WILL NOT GO WITH A FLASH FLOOD WATCH AT THIS TIME...THOUGH RAINFALL AMOUNTS COULD REACH 1 INCH OR SO OVER A WIDE AREA. LOCATIONS THAT LOOK TO GET THE HEAVIER RAIN AMOUNTS WILL BE THE FAR NORTHERN COUNTIES OF THE FORECAST AREA.

TEMPERATURES AND WINDS ARE THE MOST DIFFICULT OF THE VARIABLES TO FORECAST TONIGHT. GIVEN THE CURRENT DEWPOINTS FEEL THAT THE FORECAST MINS ARE OKAY. WINDS ARE ANOTHER MATTER. VARIABLE TO SOUTHEAST WINDS SHOULD OCCUR AHEAD OF THE THUNDERSTORMS...WITH NORTH WINDS IN ITS WAKE.

WILL ONLY MAKE MINOR CHANGES TO THE COASTAL FORECAST.

.KHGX...NONE.

PL-40 45



UPDATED ZONES WILL BE OUT SHORTLY TO REFLECT CURRENT PRECIP TRENDS. LOBE ROTATING AROUND MID/UPPER LEVEL LOW PROVIDING JUST ENOUGH LIFT IN MID LEVELS TO SQUEEZE OUT SOME LIGHT RAIN SHOWERS ACROSS THE CNTRL AND SRN TX PNHDL. A FEW LOCATIONS MAY BE ABLE TO RECEIVE MEASURABLE PRECIP AMOUNTS SO WILL INTRODUCE POPS. HOWEVER...THINK MOST LOCATIONS WILL RECEIVE TRACE AMOUNTS.

.AMA... TX...NONE. OK...NONE.

JH



SHOWERS AND THUNDERSTORMS ARE INCREASING IN AREAL COVERAGE AS THE SHORTWAVE OVER FAR WEST TEXAS APPROACHES. ALTHOUGH MOST OF THE SEVERE WEATHER WILL REMAIN JUST SOUTH OF THE FORECAST AREA...A FEW STORMS MAY REACH SEVERE LIMITS ACROSS THE EXTREME SOUTH. THUS HAVE ADDED MENTION OF SEVERE THERE. HAVE ALSO ADJUSTED TONIGHTS LOWS A CATEGORY OR SO ACROSS THE SOUTH AS DEWPOINTS REMAIN IN THE 60S. DRIER AIR SHOULD FILTER IN LATE TONIGHT AS THE WINDS BECOME MORE NORTHERLY.

AVIATION DISCUSSION... HAD TO ADD A MENTION OF TEMPO THUNDERSTORMS BETWEEN 2 AND 4Z FOR THE WACO AREA...THIS MAY HAVE TO BE EXTENDED FOR A COUPLE OF HOURS MORE. THUNDERSTORMS HAVE ALSO FORMED SOUTH OF THE DALLAS/FORT WORTH AREA... THIS ACTIVITY WILL LIKELY REMAIN JUST SOUTH OF THE METROPLEX...SO WILL OPT NOT TO ADD THUNDERSTORSM TO METROPLEX FOR NOW. OTHERWISE.. VFR WILL PREVAIL THIS EVENING ACROSS THE METROPLEX...BUT EXPECT CIGS OF BKN-OVC015 AS WRAP AROUND SLOW MOVING UPPER LEVEL LOW. #58

.FTW...NONE.



THE LATEST KSJT REFLECTIVITY LOOP SHOWS A NARROW BAND OF SHOWERS AND THUNDERSTORMS TRAINING ALONG THE STALLED COLD FRONT WHICH WAS LOCATED ALONG A DFW TO JCT LINE. THE ETA DID SHOW A SHORTWAVE ROTATING INTO OUR SRN ZONES THIS EVENING. THE COMBINATION OF THE SYNOPTIC SCALE FORCING... LOW LEVEL CONVERGENCE ALONG THE BOUNDARY... AND MARGINAL INSTABILITY SHOULD ALL BE ENOUGH TO SUSTAIN THE CONVECTION OVER OUR FAR SERN ZONES FOR A FEW MORE HOURS. AS THE UPPER LOW PUSHES FARTHER SOUTH TONIGHT... EXPECT THE COLD FRONT TO MOVE SLOWLY SOUTH ENDING THE CONVECTIVE THREAT. AS A RESULT... WILL UPDATE ZONES TO INCREASE POPS IN THE ERN HEARTLAND AND NORTHWEST HILL COUNTRY FOR EARLY TONIGHT. IN ADDITION... THE SLOWER MOVING COLD FRONT WILL KEEP TEMPS UP OVERNIGHT IN THIS AREA... SO PLAN TO BUMP LOWS UP A CATAGORY OR TWO.

.SJT...NONE.

TEW N