617 
FXUS63 KILX 221730
AFDILX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LINCOLN IL
1230 PM CDT MON APR 22 2013

.DISCUSSION...
ISSUED 1008 AM CDT MON APR 22 2013

FORECAST LARGELY ON TRACK THIS MORNING...AND HAVE ONLY MADE SOME
MINOR ADJUSTMENTS TO THE GRIDDED FORECAST TO REFLECT CURRENT
TRENDS.

FRONTAL BOUNDARY CURRENTLY EXTENDS FROM NORTHEAST WISCONSIN TO
JUST NORTH OF DES MOINES...THEN SOUTHWEST INTO NORTHWEST KANSAS. A
LARGE SHIELD OF CLOUDS HAD REACHED THE MISSISSIPPI RIVER IN
ADVANCE OF THIS SYSTEM...BUT MOST OF THE FORECAST AREA HAS BEEN
SEEING ABUNDANT SUNSHINE THIS MORNING. THE FRONT IS EXPECTED TO
BULGE A BIT NORTHWARD THIS AFTERNOON AS LOW PRESSURE DEVELOPS IN
IOWA...SO THE CLOUDS WILL REMAIN THE PRIMARY IMPACT IN OUR AREA.
HOWEVER...ENOUGH SUNSHINE AND SOUTHERLY WINDS ARE EXPECTED TO
ALLOW TEMPERATURES TO REACH THE UPPER 60S EVERYWHERE...WITH A FEW
LOWER 70S SOUTH OF I-70.

GEELHART


&&

.AVIATION...
ISSUED 1230 PM CDT MON APR 22 2013

VFR CONDITIONS EXPECTED THROUGH AT LEAST 06Z OVER CENTRAL
ILLINOIS...WITH JUST SOME LOWERING MID AND HIGH CLOUDS. HOWEVER...
CU-RULE AND SOUNDINGS SHOWING SOME SCATTERED CLOUDS AS LOW AS
4000 FEET THIS AFTERNOON FROM KSPI-KCMI. INCOMING COLD FRONT FROM
THE WEST HAS BEEN SLOWING DOWN...SO HAVE BACKED OFF ON THE VCSH
MENTION FOR A FEW HOURS UNTIL AROUND 05Z OR LATER...AND MAY BE
CLOSER TO 12Z TOWARD KDEC/KCMI. ONCE THE FRONT PASSES...SHOWERS
WILL BECOME MORE STEADY AND CEILINGS SHOULD FALL TO AROUND 2000
FEET. CURRENTLY DOES NOT APPEAR TO BE A MAJOR THREAT OF THUNDER...
BUT NAM MODEL INDICATES A LOW POTENTIAL AROUND KCMI TOWARD THE END
OF THE TAF PERIOD...SO WILL NEED TO KEEP AN EYE ON THIS.

GEELHART

&&

.PREV DISCUSSION...
ISSUED 308 AM CDT MON APR 22 2013

SHORT TERM...TODAY THROUGH WEDNESDAY

A NICE SPRING DAY AHEAD FOR CENTRAL/SE IL AS TEMPS WARM CLOSER TO
NORMAL HIGHS IN THE UPPER 60S THIS AFTERNOON OVER CENTRAL IL WITH
LOWER 70S SE OF I-70. STRONG 1042 MB HIGH PRESSURE OVER MAINE AND
NEW BRUNSWICK CANADA AND RIDGING SW INTO THE LOWER MS VALLEY TO
GRADUALLY PULL AWAY FROM IL TODAY WHILE 999 MB LOW PRESSURE
EMERGES OVER THE TEXAS PANHANDLE BY SUNSET WHILE COLD FRONT OVER
CENTRAL IA MOVES LITTLE TODAY. PARTLY TO MOSTLY SUNNY SKIES THIS
MORNING TO BECOME MOSTLY CLOUDY DURING THE AFTERNOON FROM I-55
WEST. 

LOW PRESSURE TO EJECT NE DURING TONIGHT AND TUE AS COLD FRONT
PUSHES SE INTO CENTRAL IL AND THRU SE IL TUE EVENING. THIS TO
INCREASE CHANCES OF SHOWERS AND THUNDERSTORMS FROM WEST TO EAST
DURING THIS TIME WITH BEST CHANCES TUE AND TUE NIGHT. SPC HAS 5%
RISK OF STRONG TO SEVERE STORMS OVER SE IL LATE TUE AFTERNOON AND
TUE EVENING. RAINFALL AMOUNTS OF 0.75 TO 1 INCH STILL LOOKS GOOD
WITH THIS SYSTEM WHICH COULD AGGRAVATE RIVER LEVELS ACROSS
CENTRAL/SE IL. LINGERED 20-30% CHANCE OF SHOWERS EAST OF I-57 WED
MORNING OTHERWISE DRY AND COOLER TEMPS USHERING INTO THE REGION.

LONG TERM...WEDNESDAY NIGHT THROUGH SUNDAY

HIGH CONFIDENCE WITH DRY WEATHER RETURNING FOR A TIME WED NIGHT
THROUGH FRI ACROSS CENTRAL/SE IL AS 1025-1028 MB HIGH PRESSURE
SETTLES INTO IL BY SUNSET THU AND STRENGTHENS TO 1030 MB OVER THE
EASTERN OHIO VALLEY BY DAWN FRI. CONFIDENCE LOWERS TOWARDS THE
WEEKEND AS MODELS CONTINUE TO DIFFER WITH HANDLING NEXT WEATHER
SYSTEM WITH SOME TIMING DIFFERENCES. ECMWF CONTINUES TO BE FURTHER
SOUTH WITH LOW PRESSURE AND HEAVIER QPF PASSING SOUTH OF IL WITH
LIGHT QPF INTO CENTRAL/SE IL SAT AND SAT NIGHT. GFS IS FURTHER
NORTH AND MORE AGGRESSIVE WITH SPREADING QPF ACROSS MUCH OF IL
DURING THE DAY FRI AND DIMINISH EAST OF IL BY SUNSET SAT. GEM IS
SLOWER MODEL WITH DRY CONDITIONS UNTIL SAT AFTERNOON. WILL STAY
CLOSE TO ALL-BLEND POPS FOR NOW WITH SLIGHT CHANCES BY FRIDAY
AFTERNOON AND 20-30% CHANCE POPS FRI NIGHT AND SAT...AND JUST
SLIGHT CHANCE POPS SE IL SAT NIGHT AND SUNDAY. HIGHS IN THE LOWER
60S FRI MODIFY CLOSER TO NORMAL THIS WEEKEND WITH HIGHS IN THE MID
TO UPPER 60S AND LOWS IN THE MID TO UPPER 40S.

07


&&

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

$$