Forecast Discussions mentioning ACARS, received at FSL on 01/15/01

USING THE ETA MODEL SURFACE FORECAST AND 700 MB FORECAST AND EXTRAPOLATION OF THE SAME LEVELS OF THE CYCLONE AND UPPER AIR LOW FORECAST THE LOW INTO NORTHERN MICHIGAN BY MONDAY AFTERNOON. WILL KEEP PRECIPITATION IN THE FORECAST FOR TONIGHT AND MONDAY MORNING. BASED ON 1000 TO 850 MB THICKNESS AND CURRENT ACARS SOUNDINGS WILL KEEP THE RAIN UNTIL LATE TONIGHT. THEN WILL FORECAST SNOW BUT NO ACCUMULATION. WILL MENTION FOG BUT NO ADVISORY BECAUSE THE LOW VISIBILITY AREAS ARE SCATTERED.

USING THE SATELLITE LOOPS AND FORECASTED POSITIVE VORTICITY ADVECTION IN LAYERS AND DIFFERENTIAL VORTICITY ADVECTION WILL FORECAST CLEARING MONDAY NIGHT. THE ISENTROPIC FORECAST FOR THE 285K SURFACE SHOWS SOME NEGATIVE PRESSURE ADVECTION SOUTH OF THE FORECAST AREA TONIGHT AND OVER THE FORECAST AREA MONDAY MORNING.

FOR THE EXTENDED NOTED THE POSITIVE VORTICITY ADVECTION AND SHORT WAVES ON THE 500 MB AND 300 TO 500 MB LAYER USING THE AVN AND MRF. KEPT A CHANCE OF SNOW IN THE FORECAST FOR THURSDAY AND FRIDAY. .CHI...NONE $$ WHW



LARGE SCALE...WATER VAPOR IMGRY SHOWS 00Z MDLS ON TRACK WITH SHARPENING THE STRONG UPR RDG ALG 130W. THIS WL BE THE DOMINANT FEATURE THROUGH MID WEEK...AND TO A LESSER EXTENT INTO THE WEEKEND.

SHORT TERM...RADAR SHOWS THAT PSCZ HAS FINALLY POOPED OUT...WITH MAIN PCPN THREAT THIS MORNING BEING LCL DRIZZLE IN THE VERY MOIST LOWER AIR MASS. IR SAT IMGRY AND SFC OBS SHOW CLDS PRETTY MUCH OVERCAST OVER ALL OF W WA...BUT CLEARING UP AT VANCOUVER PARTS OF FRASER VALLEY HAS ALREADY OCCURRED. BELLINGHAM IS ALREADY CLEAR...BUT WITH SMALL TEMP/DP SPREADS XPCT FOG TO FORM. SFC PRES GRADS SHOW WK BUT SLOWLY INCRSG NLY TREND AND LOW LVL WNDS FM ACARS SOUNDINGS SHOW ABT 5-15 KT FROM THE N. THUS...NLY FLOW IN PLACE FOR XPCTD CLEARING TREND. WL LEAVE MAIN THEME IN PLACE...BUT REWORD TODAY TO EXPRESS MORE WIDESPREAD CLOUDINESS AND AFTN CLRG. LESS MSTR XPCTD TUE MORNING BUT STILL IN 'AREAS' CATEGORY. 850 TEMPS STILL REMAIN COOL IN NLY FLOW...WL UNDERCUT MOS TEMPS SOME AND KEEP MAXES NR YDAS READINGS.

EXTENDED...NEW AVN/MRF/CANADIAN AND 12Z ECMWF ALL BRING A WKNG FNT THOUGH THE RDG THU NIGHT...AVN IS SLGTLY FASTER. MDLS REMAIN SMLR WITH GENERAL IDEA BUT DIFFER A BIT ON DETAILS FRI/SAT...WITH MINOR DRY PERIOD BTWN FNTS FRI/FRI NIGHT THEN NXT SYSTEM MOVING IN ON SAT. WON'T FIGHT THE MDLS THIS TIME BUT WL TRY TO WORD FCSTS TO MINIMIZE TREND CHANGES. THUS WITH FNT ARRIVING LATE THU...WL LEAVE DAYTIME MSTLY SUNNY AND PUT PCPN IN FRI PERIOD BEGINNING AT MIDNIGHT. KAM UIL 000 SEA 000 OLM 000

.KATX...VCP31/CSR32...OPERATIONAL

.SEW...NONE.