697  
FXUS63 KILX 291742  
AFDILX  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE LINCOLN IL  
1242 PM CDT SUN MAR 29 2026  
   
KEY MESSAGES  
 
- A SIGNIFICANT WARMING TREND WILL BRING TEMPERATURES WELL INTO  
THE 60S TODAY, AND NEAR 80 DEGREES BY MONDAY AND TUESDAY.  
 
- PERIODS OF SHOWERS AND THUNDERSTORMS WILL OCCUR THROUGHOUT THIS  
WEEK PROVIDING A SUBSTANTIAL MULTI-DAY RAINFALL EVENT. THERE  
IS CURRENTLY A HIGH (60-80%) PROBABILITY THAT THE WEEKLY  
RAINFALL WILL EXCEED 2 INCHES IN AREAS EAST OF THE ILLINOIS  
RIVER.  
 
 
   
DISCUSSION  
 
ISSUED AT 603 AM CDT SUN MAR 29 2026  
 
(THROUGH NEXT SUNDAY)  
ISSUED AT 308 AM CDT SUN MAR 29 2026  
 
A SIGNIFICANT WARMING TREND IS EXPECTED TODAY THROUGH TUESDAY  
AS LOW-LEVEL FLOW SHIFTS TO THE SOUTH BEHIND DEPARTING SURFACE  
HIGH PRESSURE. HIGH TEMPERATURES ARE FORECAST TO REACH WELL INTO  
THE 60S BY THIS AFTERNOON, ACCORDING TO DETERMINISTIC NBM  
GUIDANCE, BEFORE SURGING CLOSE TO 80 DEGREES ON BOTH MONDAY AND  
TUESDAY. THIS WARMER WEATHER WILL BE ACCOMPANIED BY BREEZY  
SOUTHERLY WINDS. AFTERNOON GUSTS ARE FORECAST TO PEAK BETWEEN 20  
AND 30 MPH TODAY AND MONDAY, THEN INCREASE TO THE 30-40 MPH  
RANGE ON TUESDAY AHEAD OF AN APPROACHING COLD FRONT.  
 
A WET WEEK IS ON THE WAY, BRINGING NEAR-DAILY OPPORTUNITIES FOR  
SHOWERS AND THUNDERSTORMS. THE FIRST, LOW-PROBABILITY CHANCE  
FOR SCATTERED ELEVATED STORMS ARRIVES MONDAY NIGHT, PRIMARILY IN  
NORTHERN ILLINOIS, BUT POSSIBLY EXTENDING AS FAR SOUTH AS THE  
INTERSTATE 74 CORRIDOR. THIS ACTIVITY WILL BLOSSOM AS SUBTLE  
SHORTWAVE ENERGY MOVES IN AHEAD OF A COLD FRONT AND INTERACTS  
WITH A STRONG, VEERING LOW-LEVEL JET AXIS, POTENTIALLY PRODUCING  
SOME LOW-END HAIL AND WIND.  
 
THE BETTER CHANCE FOR WIDESPREAD THUNDERSTORMS ARRIVES TUESDAY  
EVENING. BY THEN, THE COLD FRONT WILL HAVE SHIFTED SOUTHWARD  
INTO CENTRAL ILLINOIS. HOWEVER, THE SEVERE WEATHER THREAT  
REMAINS UNCERTAIN DUE TO NEBULOUS MID-LEVEL FORCING, A WELL-  
CAPPED WARM SECTOR WITH ONLY MARGINAL CAPE/SHEAR, AND  
UNCERTAINTY ABOUT THE ORIENTATION OF DEEP-SHEAR VECTORS RELATIVE  
TO THE COLD FRONT. THE SETUP MAY BE MORE CONDUCIVE TO A HEAVY  
RAIN EVENT THAN SEVERE WEATHER. CURRENT RAINFALL PROJECTIONS  
SHOW GLOBAL ENSEMBLES AGREEING ON A NARROW AXIS OF 0.5" TO 1"  
OF RAIN FROM SOUTHWEST MISSOURI TO CENTRAL INDIANA THROUGH  
WEDNESDAY MORNING, WHILE DETERMINISTIC MODELS SUGGEST LOCALIZED,  
CONVECTIVELY-ENHANCED AMOUNTS THAT COULD REACH 2".  
 
WEDNESDAY AFTERNOON COULD BRING A BRIEF RETURN TO DRIER AND  
COOLER CONDITIONS AS AN ELONGATED SURFACE HIGH-PRESSURE SYSTEM  
QUICKLY MOVES ACROSS THE REGION UNDER RISING MID-LEVEL HEIGHTS.  
TEMPERATURES ARE EXPECTED TO DROP SIGNIFICANTLY, BY 20-25  
DEGREES BEHIND THE FRONT, RESULTING IN AFTERNOON HIGHS IN THE  
50S AREAWIDE.  
 
A DISTINCT SHORTWAVE TROUGH MOVING OVER THE CENTRAL U.S. IS  
EXPECTED TO BRING ADDITIONAL SHOWERS AND THUNDERSTORMS FROM  
WEDNESDAY NIGHT INTO THURSDAY. UNCERTAINTY REMAINS REGARDING THE  
EXACT PATH OF THE ASSOCIATED SURFACE LOW, SPECIFICALLY WHETHER  
IT WILL TRACK ALONG THE ILLINOIS RIVER OR THE OHIO RIVER.  
HOWEVER, MODEL TRENDS OVER THE PAST 24 HOURS, INCLUDING BOTH THE  
EPS AND GEFS, FAVOR THE MORE NORTHERN TRAJECTORY. CURRENT  
PROJECTIONS INDICATE A RAIN AXIS EXTENDING FROM SOUTHWEST  
MISSOURI TO SOUTHWEST MICHIGAN, WITH EXPECTED ACCUMULATIONS OF  
0.75" TO 1.5" THROUGH THURSDAY. WHILE THIS NEXT ROUND OF HEAVY  
PRECIPITATION CARRIES SOME THUNDERSTORM POTENTIAL, THE  
CAPE/SHEAR PARAMETER SPACE IS LESS FAVORABLE FOR SEVERE WEATHER.  
 
GLOBAL FORECAST MODELS CONTINUE TO INDICATE A SIGNIFICANT  
UPPER-LEVEL TROUGH AND FRONTAL SYSTEM APPROACHING BY NEXT  
WEEKEND, LIKELY BRINGING ANOTHER ROUND OF SHOWERS AND  
THUNDERSTORMS. DUE TO PRECEDING RAINFALL EVENTS, THE GROUND WILL  
BE SATURATED, INCREASING THE POTENTIAL FOR NOTABLE URBAN AND  
SMALL STREAM FLOODING WITH ANY MODERATE TO HEAVY RAINFALL. WHILE  
THE THREAT FOR SEVERE WEATHER REMAINS UNCERTAIN FOR THIS  
PERIOD, THERE IS A HIGH PROBABILITY (60-80%), ACCORDING TO OUR  
100-MEMBER ENSEMBLE, THAT THIS EVENT WILL PUSH THE WEEKLY  
RAINFALL TOTAL OVER 2 INCHES IN AREAS EAST OF THE ILLINOIS RIVER  
VALLEY.  
 
 
   
AVIATION /18Z TAFS THROUGH 18Z MONDAY/  
 
ISSUED AT 1242 PM CDT SUN MAR 29 2026  
 
VFR CONDITIONS WILL PREVAIL THROUGH THE ENTIRE 18Z TAF PERIOD.  
AN AREA OF CLOUDS AT AROUND 5000FT WILL SPREAD EASTWARD TO THE  
I-57 CORRIDOR BY 19Z...WITH OVERCAST CONDITIONS EXPECTED ACROSS  
THE BOARD FOR THE REMAINDER OF THE AFTERNOON. WHILE THESE CLOUDS  
MAY TEND TO THIN AT TIMES THIS EVENING AND OVERNIGHT, THEY WILL  
NOT COMPLETELY CLEAR THE TERMINALS UNTIL MID-MORNING MONDAY.  
WINDS WILL INITIALLY BE S WITH GUSTS TO AROUND 20KT THIS  
AFTERNOON, THEN WILL DECREASE INTO THE 10-15KT RANGE BY SUNSET.  
MODELS INDICATE A STRENGTHENING LOW-LEVEL JET AFTER DARK, SO  
HAVE INCLUDED 40-50KT OF WIND SHEAR AT ALL SITES AFTER 03Z  
ACCORDINGLY. SOME OF THIS HIGHER MOMENTUM AIR WILL MIX TO THE  
SURFACE MONDAY MORNING, RESULTING IN SW WIND GUSTS OF 20-25KT AT  
THAT TIME.  
 
 
   
ILX WATCHES/WARNINGS/ADVISORIES  
 
NONE.  
 
 
 
 
 
KEY MESSAGES...MJA  
DISCUSSION...MJA  
AVIATION...BARNES  
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