825
FXUS63 KLOT 222331
AFDLOT
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHICAGO/ROMEOVILLE, IL
631 PM CDT WED JUL 22 2026
KEY MESSAGES
- HAZARDOUS SWIMMING AND BOATING CONDITIONS WILL PERSIST AT
SOUTHERN LAKE MICHIGAN BEACHES THROUGH TONIGHT.
- HEAT, HUMIDITY, AND CHANCES FOR STORMS WILL RETURN EARLY NEXT
WEEK.
DISCUSSION
ISSUED AT 215 PM CDT WED JUL 22 2026
REGIONAL SURFACE OBSERVATIONS AND GOES VISIBLE SATELLITE
IMAGERY DEPICT ATMOSPHERIC CONDITIONS THIS AFTERNOON THAT ARE
MORE TYPICAL FOR SEPTEMBER OR EARLY OCTOBER RATHER THAN JULY
WITH FAIRLY EXPANSIVE, BROKEN STRATOCUMULUS COVERAGE NOTED
ACROSS THE UPPER MIDWEST AMIDST SURFACE TEMPERATURES IN THE MID
60S TO MID 70S. THE INTRUSION OF THIS EARLY FALL-LIKE AIR MASS
YIELDED BRISK NORTHERLY WINDS OVER LAKE MICHIGAN THAT HELPED
WHIP UP SOME CHOPPY WAVES ACROSS THE LAKE'S SOUTHERN SHORES.
THESE HIGH WAVES -- ALONG WITH AN ASSOCIATED ELEVATED RISK FOR
RIP CURRENTS -- PERSIST AT SOUTHERN LAKE MICHIGAN BEACHES AT
THIS HOUR, BUT SHOULD CONTINUE TO GRADUALLY SUBSIDE INTO TONIGHT
AS THE CENTER OF A ~1022 MB SURFACE HIGH SLIDES CLOSER TO THE
AREA.
DRY WEATHER WITH COMFORTABLE HUMIDITY LEVELS WILL CONTINUE INTO
TOMORROW AS THE SURFACE HIGH POSITIONS ITSELF OVER THE SOUTHERN
GREAT LAKES. TOMORROW'S HIGH TEMPERATURES WILL BE A FEW DEGREES
HIGHER THAN TODAY'S HIGHS, AND TEMPERATURES WILL WARM FURTHER
ON FRIDAY AND INTO THE WEEKEND AS THE PRESENT AIR MASS IS
PRODDED EASTWARD BY A BUILDING MID- TO UPPER-LEVEL RIDGE ACROSS
THE CENTRAL THIRD OF THE COUNTRY. AN UPPER-LEVEL SHORTWAVE WILL
ALSO DRIFT SOUTHEASTWARD ACROSS THE LOWER MIDWEST ON FRIDAY AND
WILL BE ACCOMPANIED BY RAIN. ACCORDING TO THE MAJORITY OF THE
LATEST FORECAST GUIDANCE, THE LINGERING INFLUENCE OF THE
AFOREMENTIONED HIGH PRESSURE SHOULD TEND TO KEEP THIS RAIN
SUPPRESSED OFF TO OUR SOUTHWEST AND SOUTH. HAVE THUS MAINTAINED
A DRY FORECAST FOR FRIDAY, BUT COULDN'T RULE OUT NEEDING TO
INTRODUCE MENTIONABLE POP CHANCES FOR OUR SOUTHERN COUNTIES AT
SOME POINT IF GUIDANCE AS A WHOLE TRENDS A LITTLE FARTHER TO THE
NORTH/NORTHEAST WITH THIS PRECIPITATION.
BY EARLY NEXT WEEK, DECIDEDLY MORE JULY-LIKE CONDITIONS WILL BE
IN PLACE ACROSS THE REGION ONCE AGAIN WITH TEMPERATURES
BUILDING INTO THE UPPER 80S AND 90S. DEW POINTS ARE ALSO
EXPECTED TO CLIMB INTO THE 70S (AND POSSIBLY WELL INTO THE 70S)
AS RICH GULF MOISTURE DRIFTS INTO THE REGION AND IS ENHANCED BY
EVAPOTRANSPIRATIONAL PROCESSES OCCURRING ACROSS CROPLAND. HEAT
INDICES WILL THUS AT LEAST APPROACH, AND COULD POTENTIALLY
EXCEED, THE 100 DEGREE MARK ON SUNDAY AND AGAIN ON MONDAY. IN
ADDITION, THIS JUICY AIR MASS WILL LIKELY SUPPORT EPISODIC
THUNDERSTORM CHANCES ACROSS THE REGION WHILE IT IS IN PLACE. THE
ELEVATED LEVELS OF MOISTURE AND INSTABILITY THAT WILL BE
PRESENT ACROSS THE REGION DURING THIS TIME FRAME WILL LIKELY
SUPPORT THREATS FOR SEVERE THUNDERSTORMS AND FLASH FLOODING
SOMEWHERE IN THE MIDWEST AS WELL, THOUGH ONLY TIME WILL TELL
PRECISELY WHERE AND WHEN SUCH THREATS MAY MATERIALIZE EARLY NEXT
WEEK.
OGOREK
AVIATION /00Z TAFS THROUGH 06Z FRIDAY/
ISSUED AT 630 PM CDT WED JUL 22 2026
NORTHEAST WINDS WILL BECOME LIGHT AND VARIABLE THIS EVENING AS
SURFACE HIGH PRESSURE EXPANDS ACROSS THE REGION. A WEAK LAKE
BREEZE IS EXPECTED TO TURN WINDS EASTERLY THURSDAY AFTERNOON
NEAR THE LAKE. HAVE MAINTAINED AN EARLY AFTERNOON TIMING AT
ORD/MDW FOR NOW THOUGH CONFIDENCE IN TIMING AND HOW FAR INLAND
IT REACHES REMAINS LOW. WINDS THEN BECOME LIGHT AND VARIABLE
AGAIN WITH SUNSET. SCT TO BKN VFR CUMULUS CAN BE EXPECTED AGAIN
ON THURSDAY WITH INCREASING HIGH CLOUDS EXPECTED TOWARD THE END
OF THE PERIOD.
PETR
LOT WATCHES/WARNINGS/ADVISORIES
IL...BEACH HAZARDS STATEMENT UNTIL 10 PM CDT THIS EVENING FOR
ILZ006-ILZ103-ILZ104.
IN...BEACH HAZARDS STATEMENT THROUGH THURSDAY MORNING FOR INZ001-
INZ002.
LM...SMALL CRAFT ADVISORY UNTIL 10 PM CDT THIS EVENING FOR THE IL
NEARSHORE WATERS.
SMALL CRAFT ADVISORY UNTIL 4 AM CDT THURSDAY FOR THE IN
NEARSHORE WATERS.
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