273
FXUS63 KILX 090521
AFDILX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LINCOLN IL
1221 AM CDT TUE JUN 9 2026
KEY MESSAGES
- A HEAVY RAIN THREAT WILL PERSIST THROUGH THIS EVENING,
CONTINUING INTO THE OVERNIGHT HOURS SOUTH OF I-72/DANVILLE.
RATES OF TWO INCHES PER HOUR OR GREATER MAY LEAD TO LOCALIZED
FLASH FLOODING.
- THE COMBINATION OF HEAT AND HUMIDITY WILL LEAD TO HEAT INDEX
VALUES PEAKING BETWEEN 95 AND 105 DEGREES ON TUESDAY AND
WEDNESDAY. THOSE SENSITIVE TO HEAT SHOULD TAKE EXTRA
PRECAUTIONS.
- THE THREAT FOR SEVERE WEATHER WILL INCREASE THROUGH THIS
WEEK, PEAKING IN THE LATE WEDNESDAY NIGHT-THURSDAY TIME FRAME.
UPDATE
ISSUED AT 935 PM CDT MON JUN 8 2026
MADE SOME TWEEKS TO THE POP/WX GRIDS TO BETTER REFLECT RADAR
TRENDS FOR THE REST OF THE NIGHT. SOME OF THE NEW MODELS ARE
INDICATING CHANCES OF PRECIP TOMORROW IN THE EAST AND CENTRAL
PARTS OF THE STATE, SO MADE SOME ADJUSTMENTS FOR TOMORROW AS
WELL. ADDITIONAL SHOWERS ARE POSSIBLE OVERNIGHT, BUT CHANCES ARE
LESS THAN EARLIER FORECASTED. UPDATE SHOULD HAVE ALREADY GONE
OUT.
DISCUSSION
ISSUED AT 241 PM CDT MON JUN 8 2026
NEAR RECORD PRECIPITABLE WATER VALUES OF JUST OVER 2" ALONG WITH
AN APPROACHING UPPER LOW ARE DRIVING A HEAVY RAIN THREAT TODAY,
WITH MULTIPLE REPORTS OF 2"/HOUR RAIN RATES. EAST CENTRAL IL
WILL SEE THE GREATEST THREAT FOR HEAVY RAIN OVER THE NEXT FEW
HOURS. AN MCV MOVING OUT OF SOUTHEAST MO MAY LEAD TO
THUNDERSTORM DEVELOPMENT IN PORTIONS OF SOUTHEASTERN IL THAT
HAVE YET TO SEE MUCH ACTIVITY. SOME WILL SEE A BRIEF BREAK THIS
AFTERNOON, BUT WITH MORE SHOWERS/STORMS CAPABLE OF HEAVY
RAINFALL MOVING IN FROM THE WEST WE ANTICIPATE THE FLOOD THREAT
TO PERSIST THROUGH AT LEAST THIS EVENING. A FEW CAMS DEPICT A
CONVECTIVE COMPLEX WITH AN ASSOCIATED MCV MOVING ACROSS MO AND
WEAKENING DURING THE OVERNIGHT HOURS. THE SOUTHERN PORTION OF
THE FLOOD WATCH HAS BEEN EXTENDED TO 7 AM TO ACCOUNT FOR THIS
POSSIBILITY, AS WELL AS TO ACCOUNT FOR THE PERSISTENT NEAR
RECORD PW VALUES.
THE COMBINATION OF HEAT AND HUMIDITY THEN BECOME A CONCERN FOR
TUESDAY AND WEDNESDAY. HEAT INDEX VALUES IN THE MID 90S UP TO
A FEW DEGREES OVER 100 ARE ANTICIPATED. PARTICULARLY FOLLOWING
THE EXTENDED PERIOD OF DRY AND COOL CONDITIONS EXPERIENCED
TOWARD THE END OF MAY/IN THE FIRST WEEK OF JUNE, THIS PERIOD OF
HEAT AND HUMIDITY COULD HAVE MORE IMPACT THAN USUAL. ON TUESDAY,
A WEAK MOISTURE BOUNDARY MAY TRIGGER ISOLATED THUNDERSTORMS BUT
LITTLE RELIEF FROM THE HEAT WILL PROBABLY RESULT. INSTABILITY IS
QUITE STRONG, BUT WITH SHEAR LIMITED THE SEVERE THREAT SHOULD BE
LIMITED AS WELL. THE MAIN CONCERN WOULD BE ISOLATED STRONG TO
SEVERE WIND GUSTS.
THE SEVERE WEATHER THREAT IS FORECAST TO INCREASE LATER IN THE
WEEK FOR CENTRAL AND SOUTHEAST ILLINOIS. LATE WEDNESDAY NIGHT
INTO THURSDAY MORNING, SEVERE STORMS COMING OUT OF THE UPPER
MISSISSIPPI VALLEY ARE FORECAST TO WEAKEN AS THEY MOVE TOWARD
CENTRAL ILLINOIS. THE GREATER THREAT IS ANTICIPATED ON THURSDAY
AFTERNOON/EVENING, WITH SPC DELINEATING A 30% CONTOUR
APPROXIMATELY NEAR AND WEST OF I-55.
AVIATION /06Z TAFS THROUGH 06Z WEDNESDAY/
ISSUED AT 1221 AM CDT TUE JUN 9 2026
AREA OF IFR CEILINGS EXTENDS FROM KGBG-KBMI NORTHWARD THIS HOUR,
WITH SATELLITE DATA SHOWING CONTINUED REDEVELOPMENT ALONG THE
SOUTHERN EDGE. WHILE KPIA/KBMI HAVE SEEN BREAKS IN THE STRATUS
AT TIMES, WILL GO ON THE PESSIMISTIC SIDE WITH THE NEW TAF'S AND
KEEP THEM IFR/LIFR THE NEXT FEW HOURS. SOME ADDITIONAL
DEVELOPMENT OF CEILINGS BELOW 3000 FEET IS ANTICIPATED OVER
CENTRAL ILLINOIS, WHICH IS EXPECTED TO PERSIST A GOOD PART OF
THE MORNING.
DEVELOPMENT OF NEW SHOWERS/STORMS IS EXPECTED WITH SOME OF THE
DAYTIME HEATING, THOUGH COVERAGE SHOULD BE MUCH LESS THAN ON
MONDAY. CURRENTLY FOCUSING ON THE KSPI-KCMI CORRIDOR WITH PROB30
MENTIONS, THOUGH AN ISOLATED SHOWER/STORM FURTHER NORTH CAN'T BE
RULED OUT.
ILX WATCHES/WARNINGS/ADVISORIES
FLOOD WATCH UNTIL 1 AM CDT EARLY THIS MORNING FOR ILZ027>031-
036>038-041>046-053-055-057.
FLOOD WATCH UNTIL 7 AM CDT THIS MORNING FOR ILZ040-047>052-054-
056-061>063-066>068-071>073.
KEY MESSAGES...AAT
UPDATE...AUTEN
DISCUSSION...AAT
AVIATION...GEELHART
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