FXUS63 KPAH 291148 AAA
AFDPAH

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE PADUCAH KY
548 AM CST SUN NOV 29 2009

.UPDATE...
DISCUSSION FOR 12Z SUNDAY ROUTINE TAF ISSUANCE.

NO CHANGE TO PREVIOUS PUBLIC DISCUSSION.

&&

.DISCUSSION...
/LAST ISSUED 325 AM CST SUN NOV 29 2009/
FORECAST ISSUES THIS AM CENTER MAINLY AROUND A DEVELOPING STORM
SYSTEM TOWARD MID WEEK.

COLD FRONT WILL MOVE INTO THE REGION TODAY. NOT MUCH GOING ON PRECIP 
WISE THIS AM ALONG THE FRONT...BUT THIS SHOULD GRADUALLY CHANGE 
DURING THE DAY AS MID LEVEL ENERGY DIGS EAST INTO THE CENTRAL AND 
NRN PLAINS. SHOWERS SHOULD BEGIN TO BREAK OUT...ESP DURING THE 
AFTERNOON AND INTO THE EVENING HOURS ALONG AND BEHIND THE SFC 
FRONT...WHICH SHOULD BE CLOSE TO THE OH RVR BY EARLY EVENING. 
BELIEVE HIGHEST QPF WILL BE OVER WRN KY...WHERE A QUARTER INCH OR SO 
MAY FALL TONIGHT.  

AFTER A BRIEF REPRIEVE TUESDAY...RAIN CHANCES RETURN IN EARNEST WED 
AND WED NIGHT. THERE CONTINUES TO BE CONSIDERABLE MODEL DISCREPANCY 
WITH THE EVOLUTION OF THIS MID LVL SPLIT FLOW REGIME. THE 00Z GFS 
CONTINUES TO BE THE SOUTHERN OUTLIER OF ALL MODELS...AND SUGGESTS 
LITTLE IF ANY RAINFALL AT ALL. DECIDED TO USE MORE OF A 
ECMWF/CANADIAN/SREF BLEND AND BRING THE SRN STREAM H50 LOW FURTHER 
NW...WHICH WOULD PAINT QUITE A BIT OF QPF OVER THE REGION WED AND 
WED NIGHT...ESP ALONG AND S OF THE OH RVR. REALLY DO NOT LIKE TO 
THROW OUT THE OPERATIONAL GFS COMPLETELY...BUT CANNOT FIND ANY OTHER 
MODEL TO SUPPORT ITS SOLUTION AT THIS TIME. REALLY BELIEVE...AS THE 
ECMWF SUGGESTS...THAT MOST OF THE PRECIP WILL BE SHUT DOWN BEFORE 
ENOUGH COLD AIR FILTERS DOWN INTO THE BOUNDARY LAYER TO CHANGE THE 
RAIN OVER TO SNOW. HOWEVER...THERE MAY BE A COUPLE HOUR WINDOW LATE 
WED NIGHT WHERE THE PRECIP CHANGES BRIEFLY TO WET SNOW. WOULD NOT BE 
AN ISSUE THO AS SFC TEMPS SHOULD STAY ABOVE THE FREEZING MARK.  

MADE LITTLE CHANGES BEYOND WED NIGHT. WILL USE ECMWF 2M TEMPS WITH 
WED/WED NIGHT SYSTEM.

&&

.AVIATION...
AT THE START OF THE 12Z TAF PACKAGE...VFR CEILINGS CONTINUE TO
EXPAND ACROSS EACH OF THE WFO PAH TAF SITES IN ADVANCE OF THE
SLOWLY APPROACHING COLD FRONT. AS THE FRONT APPROACHES...CEILINGS
ARE REDUCED TO MVFR CATEGORY BETWEEN 17Z-19Z. A BRIEF INTRODUCTION
TO IFR CEILINGS WERE NOTED BETWEEN THE 20Z SUNDAY TO 04Z MONDAY
TIME FRAME FOR ALL SITES...EXCEPT KEVV TO ACCOUNT FOR FRONTAL/POST
FRONTAL CLOUD COVER. THERE IS SOME POTENTIAL FOR LIGHT DRIZZLE AT
KPAH/KOWB AFTER 06Z MONDAY...BUT VISIBILITY IMPACT SHOULD REMAIN
IN THE VFR CATEGORY...DESPITE THE MVFR CEILINGS.

&&

.PAH WATCHES/WARNINGS/ADVISORIES...
KY...NONE.
MO...NONE.
IL...NONE.
IN...NONE.
&&

$$

SMITH