Forecast Discussions mentioning ACARS, received at FSL on 06/07/99

COLD AMS SETTLING OVR WRN WA WITH MULTIPLE ACARS SOUNDINGS REPORTING -28C AT 500 MB THIS AFTERNOON. EVEN WITH LITTLE SUNSHINE AMS UNSTBL ENOUGH TO KICK OFF ISOLATED CONVECTION OVER THE NORTHERN PORTION OF THE AREA. BETTER CHANCE FOR MORE WIDESPREAD CONVECTION MONDAY AFTERNOON AS UPPER LEVEL LOW ALONG BC COAST DROPS DOWN OVER WRN WA WITH A LITTLE BIT COLDER TEMPS ALOFT. MODEL LI'S FOR MON AFTERNOON BETWEEN 0 AND -2. CONVECTIVE TEMPS OFF MODEL SOUNDINGS IN THE LOWER 50S. SATELLITE IMAGERY SHOWING RIDGE BUILDING OUT ALONG 150W. THIS WILL SHIFT EASTWARD AND KICK THE WEAKENED UPPER LEVEL LOW E OF WA BY TUESDAY NIGHT WITH DRIER NWLY FLOW ALOFT BEGINNING OVER WRN WA DURING THE DAY ON TUE. .EXTENDED...MODELS SLIGHTLY DIFFERENT BUT IDEA STILL THE SAME WITH HIGH AMPLITUDE RIDGE TO THE NORTH WITH WEAK ZONAL FLOW CUTTING UNDERNEATH THE RIDGE OVER OREGON. END RESULT FOR WA WILL BE A DRYING AND WARMING TREND. SYSTEM DROPPING OUT OF THE GULF OF ALASKA ALONG 140W ON FRI PUMPING UP SHORTWAVE RIDGE OVER WA FOR THE WARMEST DAY WE HAVE HAD IN JUNE. FELTON

UIL 886 SEA 655 OLM 655

.KATX...VCP21/CSR21...OPERATIONAL. .SEW...SCA COAST FOR HEAVY SWELL.

KUIL SOUNDING AND ACARS OBS CONFIRM WHAT WE ALREADY KNOW. ITS COLD OUT THERE. 500 MB TEMPS NEAR -30C WITH FREEZING LEVEL 3900 FEET AT FORKS AND A LITTLE LOWER OVER THE CASCADES. SATELLITE IMAGES SHOW VORT MAX OFF NRN OREGON COAST MOVING INLAND AT 15Z. MODELS LOOK TO BE SLOW WITH THIS FEATURE BUT THE END RESULT IS THE SAME FOR WRN WA WITH UNSTABLE AMS AND SHOWERS TODAY. CONVECTIVE TEMPERATURES IN THE LOWER TO MID 50S THIS AFTERNOON SO NUMBER OF THUNDERSTORMS DEPENDENT ON HOW MUCH SUNSHINE WE GET. MID LEVEL MOISTURE ASSOCIATED WITH THE VORT MAX GOING INTO NRN OREGON COVERING THE AREA NOW BUT ONCE THAT FEATURE MOVES BY TO THE SOUTH AND EAST THIS AFTERNOON ENOUGH SUN TO KEEP THUNDERSTORMS IN THE FORECAST FOR LATE AFTERNOON AND EVENING. AMS BEGINS SLOW STABILIZATION TOMORROW WITH TEMPS ALOFT BEGINNING TO WARM AS UPPER LEVEL TROF SHIFTS TO THE EAST IN RESPONSE TO UPPER LEVEL RIDGE BUILDING ALONG 140W. STILL A COUPLE OF VORT LOBES LEFT IN THE NORTHERLY FLOW ALOFT TOMORROW BUT MOST OF THE DYNAMICS STAY NORTH AND EAST OF WRN WA. WILL STAY WITH MAX TEMPS IN THE LOWER 60S BUT ONSHORE FLOW TO KEEP PLENTY OF CLOUD COVER OVER THE AREA. STAT OF THE DAY ...RECORD NUMBER OF CONSECUTIVE DAYS WITH HIGHS IN THE 50S IN JUNE IN SEATTLE IS FOUR SET BACK IN 1953. IF WE DON'T GET TO 60...IT WILL BE CLOSE...TODAY WILL BE THE FOURTH DAY IN A ROW WITH HIGHS IN THE 50S IN SEATTLE. FELTON

UIL 864 SEA 653 OLM 753

.KATX...VCP21/CSR21...OPERATIONAL. .SEW...NONE.