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000 FXUS63 KILX 240148 AFDILX AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE LINCOLN IL 848 PM CDT THU OCT 23 2008 .DISCUSSION... ISSUED 848 PM CDT THU OCT 23 2008 LARGE AREA OF RAIN CONTINUES TO SPREAD NORTH ACROSS THE STATE THIS EVENING. BASED ON RADAR MOSAIC LOOP EXPECT THIS TO CONTINUE OVERNIGHT...ESPECIALLY IN EASTERN PARTS OF CWA. CURRENT FORECAST FOR OVERNIGHT HAS A GOOD HANDLE ON CURRENT SITUATION AND DO NOT SEE ANY NEED TO UPDATE AT THIS TIME. THEREFORE...NO UPDATE REQUIRED AT THIS TIME. AUTEN && .AVIATION... ISSUED 617 PM CDT THU OCT 23 2008 RAIN WILL CONTINUE THIS EVENING AND INTO THE OVERNIGHT. SPI AND PIA SHOULD SEE PCPN WANE SOONER THAN THE REST SO GOING WITH ENDING TIME OF AROUND 06Z. OTHER SITES WILL BE AN HOUR OR TWO AFTER THAT SO HAVE 07Z FOR BMI AND DEC...AND 08Z FOR CMI. CIGS WILL BE IFR THROUGH THE PERIOD UNTIL PCPN DECREASES LATE TONIGHT. THEN MVFR CIGS ARE EXPECTED AFTER THE RAIN ENDS AND UNTIL TOMORROW MORNING. DO EXPECT CIGS TO LIFT UNDER THE UPPER LEVEL LOW THAT WILL BE AFFECTING THE AREA TOMORROW...BUT ONLY TO AROUND 2-2.5KFT. WITH UPPER LVL LOW NEAR US AND LOTS OF LOW LEVEL MOISTURE FOR PCPN TODAY...EXPECT SCATTERED COLD AIR ADVECTION SHOWERS TO IN THE AREA TOMORROW MOST OF THE DAY. THE SCATTERED NATURE OF THE PCPN WARRANTS A VCSH FOR NOW. SOUTHEAST WINDS WILL BECOME SOUTHERLY TOMORROW BUT GRADIENT LOOSE ENOUGH SO AS NOT EXPECTING ANY GUSTS. AUTEN && .PREV DISCUSSION... ISSUED 200 PM CDT THU OCT 23 2008 LATEST SURFACE ANALYSIS INDICATING LOW PRESSURE OVR NORTHEAST KANSAS WITH A FRONTAL BOUNDARY EXTENDING EAST FROM THE LOW INTO EXTREME WESTERN ILLINOIS. BAND OF LIGHT TO MODERATE RAIN CONTINUES TO MOVE NNW ACRS WESTERN AND CNTRL IL WITH SATELLITE AND SFC OBS INDICATING A NARROW DRY SLOT EXTENDING FROM ERN MO NORTH INTO SE IOWA. THE CLOSED UPPER LOW OVER EASTERN KANSAS EARLY THIS AFTERNOON WILL BE THE MAIN WEATHER MAKER FOR THE NEXT COUPLE OF DAYS ACRS CENTRAL ILLINOIS. STRONG COLD FRONT STILL EXPECTED TO PUSH THRU THE AREA ON SUNDAY BRINGING THE THREAT FOR FREEZING TEMPERATURES MONDAY AND TUESDAY MORNINGS. SHORT TERM...TONIGHT THROUGH SUNDAY THE VERTICALLY STACKED SYSTEM TO OUR WEST WILL SLOWLY EDGE EAST ACRS CNTRL ILLINOIS OVR THE NEXT 24 TO 36 HOURS. THE MAIN AREA OF LOW AND MID LEVEL FORCING TO THE EAST OF THE SYSTEM WL CONTINUE TO PUSH THE SOLID AREA OF LIGHT TO MODERATE RAINS ACRS THE FORECAST AREA TNT WITH THE EAST SEEING THE HIGHEST POPS...WHILE ACRS THE FAR WEST...WL CARRY 40 AND 50 POPS THIS EVENING TO TAKE INTO ACCOUNT THE LOW AND MID LVL DRY SLOT THAT WL PUSH ACRS THE AREA. AS THE UPPER LOW TRACKS INTO WRN IL ON FRIDAY...WL CONTINUE TO CARRY RATHER HIGH PRECIP CHANCES ACRS THE FORECAST AREA. FAIRLY DECENT AREA OF RAIN NOW OCCURRING UNDERNEATH THE UPPER LOW AND WE SHOULD SEE THAT TYPE OF WX ACRS CNTRL IL ON FRIDAY. WL HOLD ONTO POPS FRIDAY NIGHT AS THE UPPER LOW TRACKS INTO NE IL WITH DECREASING POPS FROM WEST TO EAST ON SATURDAY AS THE WAVE SHIFTS WELL TO OUR EAST. UP UNTIL SAT NIGHT...MODELS HAVE SHOWN SOME DECENT CONTINUITY...HOWEVER WITH THIS MRNGS RUNS...WE ARE STARTING TO SEE SOME TIMING DIFFERENCES WITH THE COLD FRONT ON SUNDAY WITH THE FASTER NAM-WRF SOLUTION LOOKING MORE REASONABLE AT THIS TIME. THIS IS SUPPORTED NOW BY THE LATEST ECWMF WHICH HAS THE STRONG FRONT PUSHING INTO OUR NW COUNTIES BY 12Z SUNDAY. BEST COLD ADVECTION LAGS ABOUT 6 HOURS BEHIND THE BOUNDARY SO WE MAY ACTUALLY SEE TEMPS REBOUND A BIT LATE SUN MORNING INTO THE AFTN HOURS... ESP ACRS OUR EAST AND SOUTHEAST. WITH THE BEST LIFT LOCATED WELL TO OUR NORTH AND EAST SUNDAY...WL CONTINUE TO CARRY A DRY FORECAST ON SUNDAY AHEAD OF AND BEHIND THE FRONTAL BOUNDARY. LONG TERM...MONDAY THROUGH THURSDAY THE SHORTWAVE THAT SHIFTS SOUTHEAST INTO THE LAKES REGION AND HELPS DEEPEN IN THE TROF OVER THE LAKES WL ONLY GRADUALLY SHIFT OFF THE EAST LATE TUE OR WEDNESDAY OF NEXT WEEK. LARGE CANADIAN HIGH PRESSURE WILL SETTLE SOUTH INTO THE MIDWEST MONDAY AND TUESDAY OF NEXT WEEK. THE ACTUAL SFC RIDGE AXIS IS FORECAST TO FINALLY MOVE INTO OUR AREA BY LATE TUESDAY NIGHT OR WEDNESDAY MORNING...SO THAT MAY BE OUR COLDEST MORNING SO FAR THIS FALL SEASON. HAVE HAD EARLY MRNG LOWS IN 30 TO 35 DEGREE RANGE STARTING MONDAY MRNG AND SEE NO REASON TO MAKE ANY SIG CHANGES AT THIS TIME. MODELS STILL SHOWING SOME VARIABILITY WITH RESPECT TO HOW MUCH LOW LVL CLOUDINESS LINGERS ACRS THE AREA EARLY NEXT WEEK...WHICH WILL AFFECT OVERNIGHT TEMPS. AS THE CENTER OF THE HIGH SHIFTS TO OUR EAST LATE WEDNESDAY INTO THURSDAY...WE SHOULD START TO SEE SOME MODERATING TEMPERATURES TOWARDS THE END OF THE WEEK AS THE UPPER LEVEL FLOW BECOMES MORE ZONAL. SMITH && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$