037 
FXUS63 KPAH 210608
AFDPAH

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PADUCAH KY
1200 AM CST SAT NOV 21 2009

.UPDATE...
REVISED AVIATION DISCUSSION FOR 06Z TAFS...NO CHANGE TO PUBLIC 
DISCUSSION.

&&

.DISCUSSION...
THIN CIRRUS CONTINUES TO STREAM INTO THE FORECAST AREA THIS 
AFTERNOON. CIRRUS IS ABOUT THE ONLY SKY COVER WE EXPECT OVER THE 
NEXT 24 HOURS...AS AMPLE SUNSHINE HELPS TO BOOST TEMPERATURES BACK 
INTO THE 60S ON SATURDAY. 

BROAD TROUGH OVER THE CENTRAL STATES WILL SPLIT INTO TWO SEGMENTS ON 
SATURDAY...WITH ONE PASSING TO OUR NORTH ACROSS THE OHIO VALLEY AND 
THE OTHER TO OUR SOUTH NEAR THE GULF COAST. THE SOUTHERN WAVE WILL 
BRING MOISTURE NORTH TOWARDS THE FORECAST AREA SATURDAY NIGHT AND 
SUNDAY. WHILE THE PRIMARY IMPACT WILL BE AN INCREASE IN CLOUDS... 
SOME LIGHT PRECIPITATION CANNOT BE RULED OUT...ESPECIALLY ACROSS 
WESTERN KENTUCKY LATE SATURDAY NIGHT AND SUNDAY. THE GFS IS MORE 
PROGRESSIVE WITH THIS WAVE AND ITS ASSOCIATED MOISTURE...AND 
INDICATES MORE SUNSHINE AND LESS OF A CHANCE OF RAIN SHOWERS...BUT 
THIS IS CONTRARY TO THE NAM AND ECMWF. GIVEN THE TRANSITIONAL NATURE 
OF THE FLOW PATTERN AT THIS TIME...CONFIDENCE IN THE DRIER GFS IS 
NOT ALL THAT GREAT RIGHT NOW...SO WILL LEAN TOWARDS A NAM/ECMWF 
BLEND.

THE NEXT CHANCE OF PRECIPITATION ARRIVES BY THE MIDDLE OF NEXT WEEK. 
CONSISTENCY AMONG THE GFS AND ECMWF DETERMINISTIC RUNS HAS NOT BEEN 
OVERWHELMING...WITH A SMORGASBORD OF EVOLUTIONS POSSIBLE. WILL RELY 
HEAVILY ON THE ENSEMBLES...WITH THE BEST CHANCE OF RAIN AT THIS 
POINT APPEARING TO BE MONDAY NIGHT THROUGH TUESDAY NIGHT. IT DOES 
APPEAR THAT DRIER AND MUCH COOLER AIR WILL ARRIVE BY THANKSGIVING 
DAY AND LAST INTO THE FOLLOWING WEEKEND. 

&&

.AVIATION...
CIRRUS CLOUDS CONTINUE TO OVERSPREAD AREAS FROM THE OHIO RIVER 
SE...TENDING TO PUSH FURTHER SE WITH THE PASSAGE OF A SHORTWAVE 
TROUGH. SOME SIGNS OF DEVELOPING FOG WITH PATCHY BR VIS DOWN TO 
6-8SM. PARTIAL CLEARING ESPECIALLY AROUND KCGI/KEVV SHOULD ALLOW 
SOME SPOTS TO DROP DOWN INTO IFR RANGE AT TIMES BETWEEN 09Z AND 14Z 
THIS MORNING. OTHERWISE VFR CONDITIONS WILL RULE INTO SATURDAY NIGHT 
AS DEEPER MOISTURE STAYS WELL TO OUR SOUTH. WINDS WILL TEND VERY 
LIGHT JUST NORTH OF DUE EASTERLY. 

&&

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

$$