772
FXUS63 KILX 141709
AFDILX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LINCOLN IL
1209 PM CDT TUE JUL 14 2026
KEY MESSAGES
- TYPICAL SUMMERTIME HEAT AND HUMIDITY WILL PREVAIL TODAY
THROUGH SATURDAY WITH HEAT INDEX VALUES PEAKING 95 TO 100 THIS
AFTERNOON AND AT OR ABOVE 100 DEGREES EACH AFTERNOON FROM
WEDNESDAY THROUGH SATURDAY.
- THERE IS A LOW CHANCE (20-30%) OF SHOWERS AND THUNDERSTORMS
THURSDAY AFTERNOON OVER CENTRAL AND SOUTHEAST IL. SHOWERS AND
THUNDERSTORMS ARE MORE LIKELY ON FRIDAY ESPECIALLY DURING THE
AFTERNOON. GUSTY WINDS AND LOCALLY HEAVY RAINS ARE POSSIBLE
WITH STRONGER CELLS. WPC/NBM HAS TRENDED HIGHER WITH BETWEEN A
QUARTER AND HALF INCH OF RAIN ON FRIDAY OVER CENTRAL AND
SOUTHEAST IL BUT SOME AREAS WILL LIKELY SEE OVER 1 INCH OF
RAIN.
DISCUSSION
ISSUED AT 300 AM CDT TUE JUL 14 2026
PATCHY SHALLOW GROUND FOG RECENTLY DEVELOP OVER PARTS OF CENTRAL
AND NW IL. LATEST CAMS LIKE HRRR AND RAP SHOW FOG FORMATION MORE
LIKELY OVER THE IL RIVER VALLEY INTO EARLY MORNING. BUT WE ARE
STARTING TO SEE 2-4 MILE VSBY AT SPI AND PARIS SO WILL EXPAND
MENTION OF PATCHY FOG FURTHER SE. THIS SHALLOW/GROUND FOG SHOULD
LIFT QUICKLY BY MID MORNING. WILL LIKELY SEE A REPEAT OF PATCHY
FOG DEVELOPMENT OVER CENTRAL IL NORTH OF I-70 OVERNIGHT INTO
EARLY WED MORNING.
A REX BLOCK PATTERN FEATURING A STRONG UPPER LEVEL HIGH
PRESSURE RIDGE OVER THE UPPER MIDWEST INTO THE SOUTHERN GREAT
LAKES AND OHIO RIVER VALLEY, AND WEAK TROUGHING OVER THE
SOUTHERN PLAINS INTO THE DEEP SOUTH WILL DOMINATE THE WEATHER
OVER IL DURING THIS WORK WEEK. ANOTHER HEAT WAVE IS UNFOLDING
FOR IL THE REST OF THIS WEEK ESPECIALLY WEDNESDAY THROUGH
SATURDAY. TEMPERATURES WILL REACH THE UPPER 80S AND LOWER 90S
TODAY WITH HEAT INDICES REACHING MID 90S TO NEAR 100 THIS
AFTERNOON (HIGHEST OVER THE IL RIVER VALLEY). HIGHS 90-95 WED
THROUGH SATURDAY WITH HEAT INDICES IN THE UPPER 90S AND LOWER
100S EACH AFTERNOON. A FEW SPOTS COULD SEE HEAT INDICES
APPROACH 105 DEGREES FROM WED-SAT AFTERNOON, BUT CURRENTLY FEEL
WE ARE SHY OF HEAT ADVISORY CRITERIA OF 105-109F. THOUGH IF WE
GET 4 OR MORE DAYS OF HEAT INDICES OF 100-105, THAT COULD
TRANSLATE INTO A HEAT ADVISORY. THE NWS HEATRISK CLIMBS INTO THE
MODERATE CATEGORY NORTH OF I-72 THIS AFTERNOON AND ACROSS MUCH
OF CENTRAL IL WEDNESDAY, AND INTO SOUTHEAST IL TOO THURSDAY
THROUGH SATURDAY AFTERNOON. THE IL RIVER VALLEY IS FORECAST TO
REACH MAJOR CATEGORY THURSDAY THROUGH SATURDAY AFTERNOON. PEOPLE
WHO ARE PARTICULARLY SENSITIVE/VULNERABLE TO HEAT SUCH AS THE
ELDERLY AND THOSE WITH HEALTH ISSUES SHOULD THEREFORE TAKE
PRECAUTIONS.
THE UPPER LEVEL RIDGE STARTS TO WEAKEN A BIT ON THURSDAY WITH
SHORT WAVES TRACKING ESE OVER SOUTHERN/SE CANADA WITH TROFFING
INTO EASTERN CANADA AND NEW ENGLAND. WE MAY SEE ISOLATED
CONVECTION AS EARLY AS THU AFTERNOON OVER CWA WITH LIGHT RETURN
SOUTH TO SW FLOW BRINGING IN MORE MOISTURE (PWATS RISING TO
1.8-2.2 INCHES THU AFTERNOON, THOUGH BETTER CHANCES APPEAR TO BE
IN SW IL AND OVER MO WHERE CAP IS WEAKER. THE BEST CHANCES OF
SHOWERS AND THUNDERSTORMS THIS WEEK OVER CWA APPEARS TO BE ON
FRIDAY, ESPECIALLY FRI AFTERNOON/EARLY FRI EVENING WITH A WEAK
DISTURBANCE MOVING IN WITH INCREASING MOISTURE. PWATS FORECAST
TO BE 2-2.4 INCHES ON FRIDAY AND WITH WEAK STEERING WINDS,
EXPECTED LOCALLY HEAVY RAINS POSSIBLE WITH THUNDERSTORMS FRI
AFTERNOON. ALSO A FEW STRONGER CELLS COULD HAVE GUSTY WINDS/WET
MICROBURSTS. BEST CONVECTION CHANCES SHIFT EAST OF IL ON
SATURDAY THOUGH WE STILL HAVE LOW CHANCES OF SHOWERS AND
THUNDERSTORMS WITH 20-40% SAT AFTERNOON (HIGHEST NEAR THE IN
BORDER).
MORE NORTHERN STREAM SHORT WAVE DEEPEN THE UPPER LEVEL TROF OVER
THE NORTHEAST THIRD OF THE US THIS WEEKEND WITH UPPER LEVEL
RIDGE RETROGRADING WESTWARD INTO THE ROCKIES AND HIGH PLAINS. A
BACKDOOR COLD FRONT COMING OUT OF THE GREAT LAKES REGION LATE
THIS WEEK COULD PUSH INTO CENTRAL IL ON SUNDAY AND SUNDAY NIGHT
AND WOULD KEEP A CHANCE OF SHOWERS AND THUNDERSTORMS AROUND.
TEMPERATURES TRENDING CLOSER TO NORMAL NEXT MON/TUE WITH HIGHS
IN THE MID TO UPPER 80S AND DEWPOINTS SLIPPING INTO THE 60S.
THE LATEST CLIMATE PREDICTION CENTER (CPC) 8-14 DAY OUTLOOK FOR
JULY 21-27TH HAS TEMPERATURES TRENDING NEAR NORMAL OVER IL, WHILE
PRECIPITATION IS TRENDING NEAR NORMAL IN WESTERN IL AND 33-40%
ABOVE NORMAL IN CENTRAL AND EASTERN IL.
AVIATION /18Z TAFS THROUGH 18Z WEDNESDAY/
ISSUED AT 1209 PM CDT TUE JUL 14 2026
HIGH PRESSURE WILL KEEP WINDS LIGHT AND SOMEWHAT VARIABLE THROUGH
THE TAF PERIOD. DIURNAL CUMULUS WILL PARTWAY TO CLEAR SKIES THIS
EVENING, WITH LOW TO MEDIUM CHANCES FOR PATCHY FOG ONCE AGAIN
OVERNIGHT INTO WEDNESDAY MORNING. A TEMPO GROUP FOR VISBY REDUCTIONS
HAS BEEN ADDED AT KPIA FOR NOW, BUT MAY NEED TO BE INCLUDED AT
ADDITIONAL SITES IF CONFIDENCE INCREASES.
ILX WATCHES/WARNINGS/ADVISORIES
NONE.
KEY MESSAGES...07
DISCUSSION...07
AVIATION...NMA
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page