000 
FXUS63 KILX 260157
AFDILX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LINCOLN IL
855 PM CDT SUN JUL 25 2004

.DISCUSSION...SURFACE FRONT IS LOCATED FROM SOUTHERN ARKANSAS TO 
EASTERN KENTUCKY...WITH A LOW PRESSURE CENTER DEVELOPING JUST EAST 
OF MEMPHIS. TO THE NORTHWEST...THE SURFACE RIDGE AXIS IS LOCATED 
FROM WISCONSIN INTO EASTERN NEBRASKA...RESULTING IN DRY 
NORTHEASTERLY LOW LEVEL FLOW OVER ILLINOIS. AN UPPER SHORTWAVE 
APPROACHING IOWA WILL CAUSE THE TENNESSEE LOW TO DEEPEN AS IT MOVES 
NORTHEAST ALONG THE FRONT. THIS WILL CAUSE DEEPER MOISTURE TO OUR 
SOUTHEAST TO BE PUSHED BACK INTO EASTERN ILLINOIS WITH 
TIME...HOWEVER EXPECT THAT ANY RAIN THREAT WILL HOLD OFF UNTIL AFTER 
TONIGHT. AREAS OF FOG STILL LOOK POSSIBLE LATER TONIGHT MAINLY OVER 
THE SOUTHEAST WHERE THERE WAS NO SUNSHINE EARLIER TODAY...WITH FOG 
DECREASING NORTHWESTWARD. 

WILL THEREFORE TAKE RAIN MENTION OUT OF THE FORECAST PACKAGE FOR THE 
REMAINDER OF THE NIGHT. CURRENT DEWPOINT FIELDS SUPPORT THE GOING 
MIN FORECASTS...SO NO CHANGES THERE.

&&

.PREV DISCUSSION...
SHORT TERM PROBLEMS STEM AROUND PCPN CHANCES TONIGHT AND TOMORROW IN 
THE EAST AND SE. LONGER TERM CONCERNS STEM AROUND PCPN CHANCES 
FRI-SAT. TEMPS TO REMAIN ON THE COOL SIDE ANOTHER COUPLE DAYS THEN A 
WARMUP THRU THE MIDDLE AND END OF THE WEEK. LEANING A LITTLE MORE 
TOWARD THE ETA MODEL IN THE SHORT TERM AS IT SEEMS TO HAVE A LITTLE 
BETTER HANDLE ON THE UPPER LOW AS IT MOVES OVER THE AREA. THE ETA 
HAS BECOME MORE BULLISH WITH THIS FEATURE AND THE GFS HAS BACKED OFF 
A LITTLE ON THE STRENGTH OF THE SYSTEM AND THE EXTENT OF THE WRAP 
AROUND PCPN.  

SHORT TERM...TONIGHT THROUGH TUESDAY NIGHT...
RADAR TRENDS INDICATING THAT THE BULK OF THE PCPN IS NOW ONLY IN 
THE FAR E-SE ZONES AND TRYING TO MOVE OUT OF THE AREA. MOS GUIDANCE 
STILL SHOWING CHC POPS OVERNIGHT IN THE E-SE. ALREADY REMOVED PCPN 
MENTION CENTRAL-WEST FOR TONIGHT AND TOMORROW. WILL COORDINATE MORE 
WITH IND BEFORE MAKING FINAL DECISION...MAY LOWER POPS TO 20 PERCENT 
IN THE E-SE AND JUST PARTLY TO MOSTLY CLOUDY ELSEWHERE. TEMPS AGAIN 
MORE OR LESS IN THE UPPER 50S. COULD BE A LITTLE PATCHY FOG E-SE 
OVERNIGHT. 

ON MONDAY...ETA MODEL MORE BULLISH WITH THE UPPER LOW AND PCPN 
PATTERN THAN THE 12Z GFS. LEANING A LITTLE MORE TOWARD THE ETA SO 
WILL KEEP LOW CHC POPS GOING E-SE FOR SHRA ACTIVITY. TEMPS STILL 
WELL BELOW NORMAL WITH READINGS MAINLY IN THE MID 70S IN THE NE WIND 
FLOW. CONTINUED WITH LOW CHC POPS IN THE E-SE MON NIGHT AS SYSTEM 
INTENSIFIES A LITTLE AND LIFTS NE. DRY AND A LITTLE WARMER ON TUE AS 
SYSTEM LIFTS OUT TO THE NE AND SLIGHTLY HIGHER HEIGHTS AND WARMER 8H 
TEMPS MOVE INTO THE AREA. 

LONG TERM...WEDNESDAY THROUGH SUNDAY...
WEDNESDAY AND THURSDAY STILL LOOK DRY OVER THE AREA. THE 12Z GFS HAS 
NOW SLOWED DOWN AND BACKED OFF SOMEWHAT IN BRINGING PCPN INTO THE 
AREA ON FRIDAY...ESPECIALLY COMPARED TO THE 00Z GFS RUN. SOME 
UNCERTAINTY ON PCPN CHANCES FRIDAY AS THE FRONT MOVES INTO THE AREA 
AND WEAKENS CONSIDERABLY. TRIED TO COORDINATE THE ISC GRIDS A BIT ON 
FRIDAY DURING THE DAY BY BRINGING PCPN CHANCES ONLY INTO THE WESTERN 
1/2 OR SO OF THE CWA...THEN CHC POPS ALL AREAS FRI NIGHT AND SAT. 
GFS LOOKS OVERDONE WITH PCPN CHANCES OVER THE AREA ON 
SUNDAY...PREFER NOT TO INTRODUCE CHC POPS JUST YET...WOULD LIKE TO 
SEE SOME RUN TO RUN CONSISTENCY FIRST. 

&&

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

&&

$$

04/HALL