000
FXUS63 KPAH 032119 AAA
AFDPAH
AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE PADUCAH KY
300 PM CST WED DEC 3 2008
.SHORT TERM.../TONIGHT THROUGH FRIDAY NIGHT/
MAIN FORECAST ISSUE IN THE SHORT TERM WILL BE WITH THE SYSTEM/COLD
FRONT MOVING THROUGH THE AREA TONIGHT...AND THE DEGREE OF COLD AIR
FOLLOWING IT.
CURRENT SATELLITE AND RADAR TRENDS SHOW PRECIP INCREASING ALONG THE
OHIO RIVER VALLEY...OUT AHEAD OF AN ADVANCING COLD FRONT IN SE MO.
THIS TREND SHOULD CONTINUE INTO THE EVENING AS THE FRONT MOVES INTO
THE REGION AND H50 SHORT WAVE DIGS SOUTHEAST INTO THE UPPER MIDWEST.
THERE LOOKS TO BE QUITE A BIT OF POST FRONTAL MOISTURE AS WELL...BUT
THE THINKING IS THAT MOST OF THE PRECIP WILL BE OVER BEFORE ENOUGH
COLD AIR GETS IN TO CHANGE THE RAIN TO SNOW. CANNOT RULE OUT A BRIEF
PERIOD OF LIGHT SNOW ON THE BACK EDGE OF THE PRECIP SHIELD...BUT IT
WOULD MOST LIKELY OCCUR WITH TEMPS ABOVE FREEZING. ALL IN
ALL...BELIEVE QPF AMOUNTS WILL STAY IN THE QUARTER TO HALF INCH
RANGE...WITH HIGHEST TOTALS OVER SE MO AND WRN KY.
COLDER (BUT DRY) AIR ON TAP FOR THE REST OF THE WEEK AS SURFACE HIGH
FROM CANADA DROPS SOUTH INTO THE REGION. MAY EVEN SEE SOME UPPER
TEENS THU NIGHT IF HIGH CLOUDS DO NOT INTERFERE. ALSO WILL LIKELY
SEE DAY TIME TEMPS NOT GET OUT OF THE 30S THU/FRI.
.LONG TERM.../FRIDAY NIGHT THROUGH NEXT THURSDAY/
FOR FRIDAY NIGHT THROUGH SATURDAY...A QUICK CLIPPER SYSTEM WILL MOVE
THROUGH THE WFO PAH FORECAST AREA. FOR NOW...REINTRODUCED A SMALL
CHANCE FOR LIGHT SNOW INTO A SMALL PART OF SOUTHEAST
ILLINOIS...SOUTHWEST INDIANA DURING THE DAY ON SATURDAY. GIVEN THE
VERY LOW QPF SUGGESTED BY THE SHORT RANGE ENSEMBLES...AS WELL AS THE
LATEST DETERMINISTIC /12Z WEDNESDAY/ RUN OF THE GFS/ECMWF...THIS
WILL MOST LIKELY END UP AS A TRACE EVENT.
FOR SATURDAY NIGHT THROUGH TUESDAY NIGHT...SLOWED THE TIME OF
ONSET OF PRECIPITATION ON MONDAY. A VERY LOW AMPLITUDE UPPER RIDGE
MOVES ACROSS THE WFO PAH FORECAST AREA...PER THE 12Z WEDNESDAY
GFS/ECMWF AND IMPLIED BY THE 00Z WEDNESDAY GEFS CONSENSUS
FORECASTS. THE SLOWER MOVEMENT OF THE SECOND SHORTWAVE /BEHIND THE
RIDGE/ MOVING THROUGH THE UPPER MIDWEST IMPLIED BY THE
AFOREMENTIONED MODELS ALLOWS FOR A LONGER RESIDENCE TIME FOR WARM
AIR ADVECTION TO SPREAD ACROSS THE AREA. WITH THE DELAY IN
MEASURABLE PRECIPITATION ONSET...THE MAIN CHANGE FOR THIS FORECAST
ISSUANCE IS TO KEEP THE PRECIPITATION TYPE IN LIQUID /RAIN/ FORM
DURING THE DAY ON TUESDAY. DECENT COLD AIR ADVECTION BEHIND THE
RAPIDLY MOVING FRONTAL BOUNDARY TUESDAY AFTERNOON WILL ALLOW FOR A
RAIN/SNOW MIX TUESDAY NIGHT.
FOR WEDNESDAY THROUGH THURSDAY...KEPT THIS FORECAST PERIOD DRY.
HOWEVER...GIVEN THE WIDE VARIABILITY OF THE GFS ENSEMBLES AND THE
OPERATIONAL GFS/ECMWF...I HAVE LOW CONFIDENCE THAT THIS FORECAST
PERIOD WILL REMAIN COMPLETELY DRY. FOR TEMPERATURES...LEANED TOWARD
THE COLDER ECMWF VS. GFS SOLUTION.
&&
.AVIATION...
A DECK OF MVFR CIGS WILL CONTINUE THIS AFTERNOON. CLOUDS WILL
GRADUALLY LOWER LATER IN THE DAY...AND WILL LIKELY DIP DOWN TO IFR
LEVELS NEAR AND BEHIND THE COLD FRONT TONIGHT. RAIN WILL ALSO
DEVELOP AHEAD OF THE FRONT AS CEILINGS LOWER...BUT AT THIS TIME...IT
APPEARS THAT VISIBILITIES SHOULD STAY AT VFR LEVELS AHEAD OF THE
FRONT. SOME DRIZZLE/LIGHT RAIN OR FOG COULD REDUCE THEM TO MVFR
LEVELS BEHIND THE FRONT. STRONG/GUSTY SOUTH SOUTHWEST WINDS AROUND
20 KTS WILL THROUGH THE DAY AHEAD OF THE FRONT...BEFORE ABRUPTLY
SHIFTING TO THE NORTH NORTHWEST BEHIND IT THIS EVENING.
&&
.PAH WATCHES/WARNINGS/ADVISORIES...
KY...NONE.
MO...NONE.
IL...NONE.
IN...NONE.
&&
$$
SHORT TERM...MEFFERT
LONG TERM...KES
