000 
FXUS63 KILX 281923
AFDILX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LINCOLN IL
230 PM CDT WED JUL 28 2004

.DISCUSSION...
HIGH PRESSURE STILL IN PLACE OVER THE MIDWEST TODAY AND WILL SLOWLY 
DRIFT EAST...PROVIDING QUIET WEATHER TONIGHT AND THURSDAY. 12Z UA 
ANALYSIS AND WV IMAGES SHOWING NEXT UPPER LEVEL SYSTEM AND SURFACE 
COLD FRONT OVER WESTERN NE AND DAKOTAS. THE 12Z 25H PLOT REVEALING A 
JET NOSING SE INTO MT. THIS JET SHOULD DEEPEN UPPER LEVEL SYSTEM. 
GFS MODEL DID A BETTER JOB INITIALIZING PLACEMENT OF THE NEXT SYSTEM 
THAN THE ETA DID. ETA MODEL INITIALIZED WITH A CUT OFF LOW AT H50 
OVER WRN KS...DIDNT SEE ANY REFLECTION OF THIS IN THE 12Z UA PLOT.  
GLANCED AT THE CANADIAN MODEL...HOWEVER IT HAD THE ILX FORECAST AREA 
MOSTLY DRY THIS WEEKEND. AS A RESULT...AGREED MORE WITH THE GFS. THE 
MAIN FORECAST CHALLENGES ARE PRECIPITATION BEGINNING AND ENDING 
TIMES...AS WELL AS TIMING OF THE NEXT SYSTEM/FRONT.

SHORT TERM...TONIGHT THROUGH THURSDAY NIGHT...
HIGH PRESSURE WILL DRIFT EAST OF THE FORECAST AREA THU...ALLOWING A 
SHIFT IN WINDS AND A SLIGHT WARM-UP BEFORE NEXT SYSTEM. SOUNDINGS AT 
ILX...SGF AND TOP INDICATING VERY DRY AIR IN PLACE AROUND 800MB AND 
UP. IN ADDITION...THE OPERATIONAL GFS FASTER THAN MOST OF THE 
ENSEMBLE MEMBERS...SO THINK FRONT WILL BE A LITTLE SLOWER THAN GFS 
SOLUTION. AS A RESULT THINK PRECIPITATION WILL HOLD OFF UNTIL 
FRIDAY. 

.LONG TERM...FRIDAY NIGHT THROUGH WEDNESDAY...
EXPECT PRE-FRONTAL TROF TO BEGIN TO MOVE INTO THE FORECAST AREA 
FRIDAY. A COLD FRONT WILL FOLLOW THIS TROF...HOWEVER SHOULD 
DISSIPATE ON FRIDAY. THE GFS HINTS AT A WAVE CARRYING TROPICAL 
MOISTURE MOVING NORTHWARD AND INTERACTING WITH THE TROF AND 
ENHANCING PRECIPITATION OVER THE SE FORECAST AREA LATE FRIDAY...KEPT 
QPFS LOW DUE TO THE UNCERTAINTY OF THIS WAVE...LATER SHIFTS MAY 
NEED TO KEEP AN EYE ON THIS THOUGH. 

THE GFS MOVES WHATS LEFT OF THE FRONT OUT OF IL LATE 
SATURDAY...HOWEVER LEFT A CHANCE OF PRECIPITATION IN THE SE DUE TO 
THE SLOWER PROGRESSION OF THE ENSEMBLE MEMBERS OF THE DEPARTING 
FRONT COMPARED WITH THE OPERATIONAL GFS MODEL. 

MONDAY THROUGH WEDNESDAY...A SLOW WARMING TREND IS IN STORE...AS 
HIGH PRESSURE RETURNS. LEFT FORECAST DRY FOR THIS PERIOD DESPITE THE 
FACT THAT THE GFS HAD ANOTHER COLD FRONT BEGINNING TO AFFECT IL ON 
WEDNESDAY...TOO MUCH UNCERTAINTY THAT FAR OUT...AS WELL AS THE 
SLOWER NATURE OF THE ENSEMBLE MEANS HOLDING THE FRONT BACK A DAY.


&&

.ILX WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
&&

$$

KELLY