386 
FXUS63 KILX 071641
AFDILX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LINCOLN IL
1040 AM CST WED JAN 7 2004

.DISCUSSION...ALREADY UPDATED GRIDS/ZONES TO MAKE SOME MINOR 
ADJUSTMENTS TO HOURLY TEMPERATURE TRENDS AND TO ALLOW FOR THE 
REMOVAL OF MENTION OF WIND CHILLS FROM THE ZONE FORECAST TEXT 
PRODUCT. TEMPS ARE NOW INTO THE TEENS ACROSS NORTH...WITH LOWER 20S 
CENTRAL AND MID 20S SOUTHEAST. STILL LOOKS LIKE FORECAST READINGS 
ARE ON TRACK. ADJUSTED HIGHS DOWN A DEGREE OR SO OVER SNOW FIELD 
ACROSS NORTH. IN ADDITION...COORDINATED WITH LONG TERM FORECASTER 
REGARDING CHANCE OF SNOW TOMORROW. HAVE ADJUSTED NORTHERN GROUP 
UPWARD TO 50 PERCENT CHANCE GIVEN MODEL TRENDS AND FORECASTS FROM 
NEIGHBORING OFFICES. QUICK LOOK AT MODELS SHOWS THE ETA MUCH DRIER 
THAN GFS IN THE LOW LEVELS. MUCH MORE ON THIS IN UPCOMING AFTERNOON 
FORECAST DISCUSSION.

&&

.PREV DISCUSSION...RIDGE OF HIGH PRESSURE BEGINNING TO MOVE 
SOUTHEAST OF REGION...SO WILL SEE SOUTHERLY WINDS RETURN TO ILLINOIS 
TODAY WITH A VERY SLOW WARMUP IN STORE. MAIN FORECAST PROBLEM IS THE 
NEXT WEATHER SYSTEM TO AFFECT THE CWA BY LATE TONIGHT AS WEAKENING 
SHORT WAVE SWINGS THROUGH THURSDAY AND THURSDAY NIGHT.

SHORT TERM...TODAY THROUGH FRIDAY...
TEMPS HAVE NOT DROPPED OFF AS MUCH AS PREVIOUS THOUGHT AS WINDS HAVE 
REMAINED BETWEEN 5 AND 10 MPH. SO DESPITE VERY DRY AIR OVER 
REGION...TEMPS RANGE FROM 10 ABOVE AT GBG TO 18 ABOVE AT LWV AS OF 
07Z. THIS WILL HELP TEMPS TO RECOVER TODAY AS WINDS SWING AROUND TO 
THE SOUTH UNDER PARTLY SUNNY SKIES.

BY TONIGHT...CLOUDS WILL RETURN TO THE REGION AHEAD OF NEXT WEATHER 
SYSTEM. THIS SYSTEM IS LACKING A GOOD MOISTURE RETURN AND UPPER 
LEVEL ENERGY...SO PRECIPITATION TO BE ON THE LIGHT SIDE. EACH 
SUCCESSIVE MODEL RUN HAS SLOWED THIS SYSTEM DOWN...SO WILL NOT SEE 
PCPN MOVE IN TIL WELL AFTER MIDNIGHT TONIGHT OVER THE NORTHERN 
PORTIONS OF THE CWA...THEN SLOWLY SPREAD SOUTHEAST. STILL FEEL THAT 
THE SOUTHERN THIRD OF CWA TO SEE A MIX OF LIGHT RAIN AND SNOW DURING 
THE DAYTIME HOURS AS THE SFC TEMPS RISE INTO THE MID TO UPPER 
30S...BEFORE SWITCHING TO ALL LIGHT SNOW DURING THURSDAY EVENING.
SYSTEM TO EXIT DURING THE DAY FRIDAY WITH SOME LINGERING FLURRIES IN 
THE MORNING FOR THE EASTERN HALF OF CWA.

AS FOR TEMPS...WILL FOLLOW MAV NUMBERS AS MET NUMBERS ARE TOO COLD 
AT NIGHT AND WAY TO WARM DURING THE DAY.

LONG TERM...FRIDAY NIGHT THROUGH TUESDAY...
AS FOR THE EXTENDED FORECAST...ONLY MADE MINOR ADJUSTMENTS TO THE 
GRIDS AS GFS/MRF CONTINUE TO SLOW DOWN WEATHER SYSTEM THAT WILL 
AFFECT CENTRAL ILLINOIS BY LATE IN THE DAY ON SUNDAY. SO FRIDAY 
NIGHT THROUGH SUNDAY WE WILL SEE TEMPS MODERATE WITH DAYTIME HIGHS 
IN THE MID 30S TO LOWER 40S AND LOWS IN THE MID TO UPPER 20S. SFC 
LOW WILL TRACK ACROSS THE GREAT LAKES REGION BRINGING A COLD FRONT 
THROUGH THE STATE BEGINNING SUNDAY NIGHT. PRECIPITATION TO BEGIN AS 
A MIX MOST LOCATIONS...BEFORE CHANGING OVER TO LIGHT SNOW SUNDAY 
NIGHT AND MONDAY. DRY WEATHER WILL RETURN MONDAY NIGHT AND TUESDAY.
&&

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

$$
BYRD/PLAHMER