446
FXUS63 KILX 271101
AFDILX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LINCOLN IL
601 AM CDT SAT JUN 27 2026
KEY MESSAGES
- THERE IS A MARGINAL RISK (LEVEL 1 OF 5) FOR SEVERE WEATHER
THIS AFTERNOON AND EVENING ALONG AND SOUTH OF A RUSHVILLE...TO
DECATUR...TO TERRE HAUTE LINE. THE MAIN RISK WILL BE ISOLATED
DAMAGING WIND GUSTS.
- THE FIRST PROLONGED HEATWAVE OF THE SUMMER WILL ARRIVE NEXT
WEEK WHEN AIR TEMPERATURES RISE INTO THE 90S AND MAXIMUM HEAT
INDEX VALUES CLIMB WELL ABOVE 100 DEGREES MONDAY THROUGH AT
LEAST THURSDAY.
DISCUSSION
ISSUED AT 405 AM CDT SAT JUN 27 2026
*** MARGINAL SEVERE WEATHER RISK ***
08Z/3AM SURFACE ANALYSIS SHOWS A STATIONARY FRONTAL BOUNDARY
EXTENDING FROM SOUTHERN INDIANA WESTWARD TO KANSAS. SEVERAL
CLUSTERS OF CONVECTION ARE ONGOING SOUTH OF THE BOUNDARY WITH
THE MOST SIGNIFICANT STORMS FOCUSED ACROSS SOUTHERN KANSAS INTO
OKLAHOMA. MEANWHILE NORTH OF THE FRONT, SCATTERED LIGHT SHOWERS
ARE EVIDENT ACROSS CENTRAL ILLINOIS. THE BOUNDARY WILL REMAIN
NEARLY STATIONARY TODAY, THEN WILL SLOWLY SHIFT NORTHWARD
TONIGHT IN RESPONSE TO RISING UPPER HEIGHTS. EXTENSIVE CLOUD
COVER WILL KEEP MUCH OF THE KILX CWA RELATIVELY STABLE TODAY:
HOWEVER, AS TEMPERATURES CLIMB INTO THE UPPER 70S AND LOWER 80S
AND DEWPOINTS HOVER IN THE LOWER TO MIDDLE 70S, MODEST
DESTABILIZATION WILL OCCUR SOUTH OF THE I-72 CORRIDOR DURING
PEAK HEATING WITH THE 00Z HREF SHOWING MEAN SBCAPES REACHING
1000-1500J/KG. WIND SHEAR WILL REMAIN QUITE WEAK, WITH THE NAM
INDICATING 0-6KM BULK SHEAR OF LESS THAN 30KT. SCATTERED
THUNDERSTORM CELLS WILL DEVELOP WITHIN THE FRONTAL ZONE, BUT
PARAMETERS DO NOT SUPPORT ORGANIZATION OR PARTICULARLY VIGOROUS
UPDRAFTS. AS A RESULT, THE RISK FOR SEVERE WEATHER WILL REMAIN
LOW...WITH A FEW OF THE STRONGER STORMS PERHAPS PRODUCING GUSTY
WINDS BETWEEN 3PM AND 10PM ALONG/SOUTH OF A RUSHVILLE...TO
DECATUR...TO TERRE HAUTE LINE. SCATTERED SHOWERS AND
THUNDERSTORMS WILL DEVELOP ACROSS THE REMAINDER OF CENTRAL
ILLINOIS LATER TONIGHT INTO SUNDAY MORNING AS THE FRONT LIFTS
NORTHWARD: HOWEVER, SEVERE WEATHER IS NOT ANTICIPATED.
*** HOT WEATHER AHEAD ***
AFTER THE RECENT STRETCH OF BELOW NORMAL TEMPERATURES, A
DISTINCT PATTERN CHANGE WILL BRING SUMMERTIME HEAT BACK TO
CENTRAL ILLINOIS FOR THE WEEK AHEAD. AS UPPER-LEVEL RIDGING
BUILDS OVER THE MIDWEST, THE PERSISTENT FRONTAL BOUNDARY WILL
GET PUSHED WELL TO THE NORTH AND TEMPERATURES WILL RISE
MARKEDLY. CLOUDS AND A FEW SHOWERS EARLY IN THE DAY WILL TEND TO
BLUNT THE WARMING TREND ON SUNDAY: HOWEVER, AFTERNOON HIGHS
WILL STILL REACH THE UPPER 80S TO AROUND 90 DEGREES. RISING
HEIGHTS AND INCREASING AMOUNTS OF SUNSHINE WILL BRING HOTTER
CONDITIONS FOR MONDAY THROUGH THURSDAY WHEN HIGHS CLIMB INTO THE
LOWER TO MIDDLE 90S. WITH DEWPOINTS IN THE MIDDLE TO PERHAPS
UPPER 70S, CORRESPONDING HEAT INDEX VALUES WILL EXCEED 100
DEGREES EACH AFTERNOON. GIVEN THE INCREASING CONFIDENCE OF AN
EXTENDED PERIOD OF HEAT/HUMIDITY, HEAT HEADLINES WILL NEED TO BE
ISSUED OVER THE NEXT FORECAST CYCLE OR TWO. CURRENT PROJECTIONS
INDICATE SOLID HEAT ADVISORY CONDITIONS (HEAT INDEX OF 105-110)
MONDAY THROUGH THURSDAY BEFORE THE RIDGE AXIS SHIFTS EASTWARD
AND ADDITIONAL CLOUD COVER AND CONVECTION CHANCES BRING A
SLIGHT COOLING BY THE END OF THE WEEK.
AVIATION /12Z TAFS THROUGH 12Z SUNDAY/
ISSUED AT 601 AM CDT SAT JUN 27 2026
IFR CONDITIONS WILL PERSIST AT THE CENTRAL ILLINOIS TERMINALS
FOR MUCH OF THE MORNING BEFORE FORECAST SOUNDINGS SUGGEST A
GRADUAL IMPROVEMENT TO MVFR TOWARD MIDDAY. THE BIG QUESTION IS
WHETHER OR NOT CLOUD BASES CLIMB TO VFR BY LATE THIS AFTERNOON
AND EVENING AS PER THE LATEST CONSSHORT/HRRR. PREVIOUS FORECAST
SHOWED THIS IMPROVEMENT AT THE I-72 SITES AND HAVE CONTINUED
THIS TREND WITH THE 12Z ISSUANCE. AS A FRONTAL BOUNDARY NORTH OF
THE OHIO RIVER LIFTS SLOWLY NORTHWARD, CEILINGS/VISBYS WILL
ONCE AGAIN DROP TO IFR LATE TONIGHT. SCATTERED SHOWERS/THUNDER
WILL DEVELOP ALONG AND AHEAD OF THE FRONT, BUT AM NOT CONFIDENT
ENOUGH WITH AREAL COVERAGE TO INCLUDE THUNDER AT THIS TIME.
ILX WATCHES/WARNINGS/ADVISORIES
NONE.
KEY MESSAGES...BARNES
DISCUSSION...BARNES
AVIATION...BARNES
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page