SOUTHWEST CALIFORNIA AREA FORECAST DISCUSSION
NWS LOS ANGELES/OXNARD CA
AFDLOX ISSUED BY THE NATIONAL WEATHER SERVICE SAN DIEGO
900 AM PDT THU AUG 19 1999
LOW CLOUDS ARE FAIRLY SOLID ALONG THE NORTH COAST OF SANTA BARBARA
COUNTY...OTHERWISE LOW CLOUDS ARE FAIRLY PATCHY. THE 1KM VIS IMAGE
AND THE 7AM CGR INDICATE THAT LOW CLOUDS ARE ALONG THE BEACHES OF
SOUTHERN SANTA BARBARA COUNTY TOO DUE TO A WEAK EDDY THERE. A ZONE
UPDATE WILL REFLECT THIS.
PRESSURE GRADIENTS ARE TRENDING OFFSHORE A BIT...EXCEPT TO THE
NORTH. IT APPEARS THAT THE SBA-SMX GRADIENT WILL BE A BIT WEAKER
THAN EARLIER EXPECTED...SO THE ZONE UPDATE WILL TREND DOWN WINDS IN
SANTA BARBARA COUNTY FOR TONIGHT. THE NKX AND ACARS SOUNDINGS SHOW
LITTLE CHANGE FROM YESTERDAY MORNING...BUT WITH WEAKER ONSHORE FLOW
HIGH TEMPS SHOULD BE SLIGHTLY WARMER TODAY. THE CURRENT FORECAST
REFLECTS THIS WELL. 12Z ETA INDICATES AN INCREASE IN 850 MB TEMPS
FOR FRIDAY...BUT 12Z NGM IS FAIRLY FLAT...SO INLAND TEMPS WILL
PROBABLY INCREASE JUST A DEGREE OR TWO.
MONSOONAL MOISTURE IS PROGRESSING NORTH AND WEST OUT OF THE GULF OF
CALIFORNIA...BUT THIS SHOULD PRIMARILY AFFECT AREAS EAST OF THE LOX
FORECAST AREA SINCE THE 700-500 MB FLOW IS DRIER AND MORE
SOUTHWESTERLY WEST OF LA. THE MOISTURE SHOULD PEAK FRIDAY DUE TO
INFLUENCE OF AN EASTERLY WAVE TO OUR SOUTHEAST...SO SOME AFTERNOON
CUMULUS COULD OCCUR AT LEAST OVER THE LA COUNTY MTNS.
LITTLE CHANGE IS EXPECTED OVER THE WEEKEND AS MODERATE ONSHORE FLOW
CONTINUES AT THE SURFACE WITH THE PERSISTENT COLD-CORE LOW OVER THE
ALEUTIANS/GULF OF ALASKA. MONSOONAL FLOW WILL REMAIN JUST EAST OF
THE FORECAST AREA. EXCEPT FOR THE IMMEDIATE COAST...WHERE COLD SEA
SURFACE TEMPS WILL RESULT IN CONTINUED BELOW NORMAL TEMPS...TEMPS
SHOULD BE NEAR NORMAL.
THE UPDATE WILL BE OUT BY 930 AM.
LAX 000
MAXWELL
.LAX...SMALL CRAFT ADVISORY...SEE LAXCWFLAX.
INTERIOR CENTRAL CALIFORNIA FORECAST DISCUSSION
NWS SAN JOAQUIN VALLEY - HANFORD CA
AFDFAT 900 AM PDT THU AUG 19 1999
PROBLEM TODAY IS VALLEY TEMPS. 24HR CHANGE SHOWING TEMPS CONTINUING
BELOW YESTERDAY AT THIS TIME...AND THE MORNING FRESNO AIRCRAFT OB
AVERAGING 5 DEGS LESS BELOW 5K. HOWEVER...ONSHORE GRADS DOWN 4 MB/S
AND PROFILER SHOWS STRONG WARMING OVERNITE ABOVE 2K. WILL LEAVE
ZONES ALONE FOR ANOTHER HOUR OR TWO TO SEE IF 24HR CHG SHOWS ANY
DECREASE. REMAINDER OF FCST LOOKS FINE. ALL POPS ZERO. BINGHAM
.HNX...NONE.
DEEP SOUTH TEXAS FORECAST DISCUSSION
NWS BROWNSVILLE TX
AFDBRO 915 AM CDT THU AUG 19 1999
HUR HUNTER AIRCRAFT SCHEDULED TO INVESTIGATE T.D. 3 LATER THIS AM.
CURRENT STLT PICS OVR GULF SHOW UPPER LOW ROTATING SOUTHWESTWARD
JUST EAST OF POR. MSAS HAS A BROAD AREA OF SFC LOW PRES OVR CENTRAL
GULF...EXTENDING SOUTH TO T.D. 3. KBRO IDENTIFIES SUM SHRAS/TSRAS
BEGINNING 60 MILES EAST OF POR AND EXTENDING E INTO THE CENTRAL
GULF. VAD WNDS HAVE NE FETCH OFF SFC TO 14K FT WITH SFC OBS SHOWING
N SFC WNDS DUE TO FUNNELING FM T.D. 3. UPPER LOW WL CONFINE T.D. 3
IN BAY OF CAMPECHE WITH LITTLE MVMT TDY.
TPC SEES NO NEED FOR WATCHES IN DEEP S TX ATTM...WITH SITUATION TOO
VAGUE TO FORMULATE A GOOD HOLD ON DEEPENING POTENTIAL AND TRACK OF
SYSTEM. THERE STILL EXISTS A POTENTIAL FOR INCREASE IN STRENGTH
PRIOR TO LANDFALL.
WL REWORD FCST TO ELIMINATE TIMELINESS WORDING FOR PM SHRAS/TSRAS.
OTHERWISE...NO CHANGES TO CURRENT ZFPBRO AND CWFBRO. 58
.BRO...NONE.