724
FXUS63 KLOT 160458
AFDLOT
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHICAGO/ROMEOVILLE, IL
1058 PM CST SUN FEB 15 2026
KEY MESSAGES
- POSSIBLE FOG ALONG/SOUTH OF I-80 TONIGHT AND POSSIBLE FOG NORTH
OF I-80 MONDAY NIGHT.
- SCATTERED SHOWERS AND A LOW CHANCE (20%) OF THUNDERSTORMS
EARLY WEDNESDAY MORNING.
- ELEVATED FIRE DANGER WEDNESDAY WITH WESTERLY WINDS GUSTING TO
30-35 MPH.
- ADDITIONAL RAIN CHANCES THURSDAY NIGHT/FRIDAY MORNING AND
POSSIBLE RAIN/SNOW CHANCES FRIDAY NIGHT/SATURDAY.
- ABOVE AVERAGE TEMPERATURES THROUGH THURSDAY, WITH RECORD
WARMTH LIKELY ON MONDAY.
UPDATE
ISSUED AT 913 PM CST SUN FEB 15 2026
MADE ADJUSTMENTS TO SKY COVER AND TEMP TRENDS TONIGHT AND
ADJUSTED UP HIGH TEMPERATURES A BIT ON MONDAY, FURTHER INTO
RECORD TERRITORY FOR CHICAGO AND ROCKFORD (SEE CLIMATE AFD
SECTION BELOW). CONCERN CONTINUES FOR FOG DEVELOPMENT NEAR AND
SOUTH OF I-80 TONIGHT INTO EARLY MONDAY, THOUGH CONFIDENCE
REMAINS ON THE LOWER SIDE.
CLOUD COVER HAS BEEN MUCH SLOWER TO MATERIALIZE UPSTREAM (AS PER
NIGHTTIME MICROPHYSICS RGB AND OBSERVATIONS). GIVEN CLEAR SKIES
AND A DECOUPLED BOUNDARY LAYER (LIGHT TO CALM WINDS), AREAS
OUTSIDE OF CHICAGO IN NORTHERN ILLINOIS HAVE QUICKLY DROPPED
BELOW MOST AVAILABLE GUIDANCE FOR OVERALL LOWS FOR TONIGHT. MID
AND HIGH CLOUD COVER WILL EVENTUALLY SPREAD IN AND SLOW THE
TEMPERATURE DROP, BUT NOT UNTIL SOME LOCALIZED MID 20S ARE
ATTAINED AT FAVORED COOL SPOTS OF INTERIOR NORTHERN ILLINOIS.
TEMPERATURES WILL THEN LIKELY RISE SOME IN THE PRE-DAWN HOURS.
FARTHER SOUTH, MUCH HIGHER DEW POINTS (MID-UPPER 30S VS. 20S TO
AROUND 30F NORTH) AND A LONGER DURATION OF CLEAR SKIES AND
LIGHTER WINDS ALOFT DO LEND TO CONCERN FOR FOG DEVELOPMENT.
CONCEPTUALLY, THERE SHOULD BE AT LEAST PATCHY FOG, INCLUDING
LOCALIZED DENSE FOG, BUT THE LACK OF BETTER GUIDANCE SUPPORT
DOES LOWER CONFIDENCE. MAINTAINED PATCHY FOG WORDING IN THE
GRIDDED FORECAST. ANY FOG AND RESULTANT LOW STRATUS SHOULD
QUICKLY DISSIPATE AFTER SUNRISE. GUSTY SOUTHWEST WINDS AND
DECREASING CLOUDS DURING EARLY-MID AFTERNOON PEAK HEATING POINT
TOWARDS A VERY MILD AFTERNOON. AS SUCH, NUDGED UP TEMPS A
COUPLE DEGREES, CLOSER TO THE MOST RECENT HRRR.
CASTRO
DISCUSSION
ISSUED AT 200 PM CST SUN FEB 15 2026
HIGHS THIS AFTERNOON ARE TOPPING OUT IN THE UPPER 50S FOR MOST
LOCATIONS WITH A FEW SPOTS TAGGING 60. A WEAK LAKE BREEZE HAS
FORMED AND WILL TURN WINDS ONSHORE AND BRING COLDER TEMPS TO
THE IMMEDIATE LAKE MICHIGAN SHORELINE THROUGH SUNSET.
FOG WILL BE A CONCERN AGAIN OVERNIGHT INTO MONDAY MORNING. MUCH
OF THE HIGH RES GUIDANCE IS SHOWING FOG DEVELOPING OVERNIGHT FOR
AREAS SOUTH OF I-80 THOUGH THERE IS STILL QUITE A BIT OF
UNCERTAINTY FOR HOW WIDESPREAD OR HOW DENSE THIS FOG MAY BECOME.
LOW LEVEL WINDS ALSO STEADILY INCREASE IN THE PREDAWN HOURS INTO
MONDAY MORNING, WHICH WOULD LIMIT THE OVERALL FOG POTENTIAL.
FROM THIS DISTANCE, INCLUDED PATCHY FOG MENTION OVERNIGHT
THROUGH MID MORNING MONDAY FOR AREAS ALONG/SOUTH OF I-80 AND
TRENDS WILL NEED TO BE MONITORED THIS EVENING.
THE INCREASING LOW LEVEL WINDS NOTED ABOVE WILL BEGIN TO MIX TO
THE SURFACE BY LATE MONDAY MORNING AND GUSTS INTO THE 25-30 MPH
ARE EXPECTED MONDAY. WHILE SOME CLOUD COVER IS EXPECTED IN THE
MORNING, SHOULD AT LEAST SEE PARTLY CLOUDY SKIES BY AFTERNOON
AND PROBABLY MOSTLY SUNNY SKIES AS TEMPS WARM INTO THE LOWER 60S
FOR MOST AREAS AND THE STRONGER SOUTHWEST WINDS WILL PREVENT A
LAKE BREEZE MONDAY AFTERNOON.
A WEAK FRONTAL BOUNDARY IS EXPECTED TO SAG SOUTH ACROSS NORTHERN
IL MONDAY NIGHT INTO TUESDAY MORNING AND THIS MAY ALLOW FOR FOG
TO DEVELOP OVERNIGHT AND CONTINUE INTO TUESDAY MORNING, NORTH OF
I-80. WHILE CONFIDENCE IS LOW, FRONTAL BOUNDARIES ARE OFTEN THE
MAIN ELEMENT NEEDED FOR FOG DEVELOPMENT AND ADDED PATCHY FOG
FOR THIS TIME PERIOD. THE PROXIMITY OF THIS BOUNDARY WILL
LIKELY MAINTAIN SOUTHEAST WINDS ACROSS MUCH OF THE AREA TUESDAY,
KEEPING AN ONSHORE WIND AND COLDER TEMPS ALONG THE IL SHORE OF
LAKE MICHIGAN. THOUGH HIGHS IN THE 50S ARE EXPECTED FURTHER
INLAND.
LOW PRESSURE WILL MOVE NORTHWEST ACROSS THE NORTHERN PLAINS AND
NORTHERN GREAT LAKES TUESDAY NIGHT INTO WEDNESDAY BRINGING A
CHANCE FOR SHOWERS TO THE LOCAL AREA, MAINLY TUESDAY NIGHT.
STILL SOME UNCERTAINTY FOR COVERAGE WITH THE BLENDED POPS NOW IN
THE LIKELY RANGE. THUNDER POTENTIAL LOOKS RATHER LOW BUT
MAINTAINED SLIGHT CHANCE (20%) MENTION FOR LATE TUESDAY NIGHT.
CURRENT TRENDS WOULD SUGGEST WHATEVER PRECIPITATION DEVELOPS
WILL BE QUICKLY SHIFTING EAST AROUND OR JUST AFTER SUNRISE
WEDNESDAY MORNING.
WEDNESDAY IS THEN LOOKING DRY AND WINDY WITH HIGH TEMPS WARMING
INTO THE MID/UPPER 60S AND WEST/SOUTHWEST WINDS GUSTING 30-35
MPH. WITH RELATIVE HUMIDITY LEVELS DROPPING INTO THE 25 TO 35
PERCENT RANGE IN THE AFTERNOON, AND DEPENDING ON THE EXTENT OF
RAIN EARLIER IN THE MORNING, AN ELEVATED FIRE DANGER MAY
DEVELOP, ESPECIALLY ACROSS THE WESTERN HALF OF THE CWA.
MODELS ARE DEVELOPING ANOTHER STORM SYSTEM THURSDAY THAT MOVES
ACROSS THE LOCAL AREA THURSDAY NIGHT INTO FRIDAY MORNING. THERE
REMAINS QUITE A BIT OF UNCERTAINTY WITH THIS SYSTEM AND ITS
STRENGTH AND LOCATION. BUT AS TRENDS LOOK NOW, THIS MAY HAVE A
BETTER CHANCE TO PRODUCE AT LEAST ISOLATED THUNDERSTORMS FOR THE
LOCAL AREA AS WELL AS A HIGHER CHANCE/COVERAGE FOR SHOWERS.
BLENDED POPS ARE NOW INTO THE 40-60 PERCENT RANGE AND THAT SEEMS
REASONABLE FROM THIS DISTANCE.
BEYOND THIS TIME PERIOD, THE OVERALL TREND LOOKS COLDER WITH
PERHAPS BELOW NORMAL TEMPS BY EARLY NEXT WEEK. THE TRANSITION TO
THIS POSSIBLE COLDER PATTERN WILL LIKELY HAVE A STORM SYSTEM
AND PRECIPITATION NEARBY, POSSIBLY WITH SOME SNOW. CMS
AVIATION /06Z TAFS THROUGH 12Z TUESDAY/
ISSUED AT 1058 PM CST SUN FEB 15 2026
KEY MESSAGES FOR THE 06Z TAFS:
- POTENTIAL FOR A BRIEF PERIOD OF LOW (IFR/LOW-LOW-MVFR) STRATUS
AROUND DAYBREAK, THOUGH CONFIDENCE IS LOWER THAN PREVIOUS.
AREAS OF FOG POSSIBLE MAINLY SOUTH OF THE TERMINALS.
- STRONG SOUTHWEST WINDS WITH GUSTS 25-30 KT MONDAY.
LIGHT SOUTH-SOUTHWEST WINDS WILL PREVAIL OVERNIGHT, BECOMING
SOLIDLY SOUTHWEST AND BREEZY MID-LATE MONDAY MORNING AS THE
GRADIENT TIGHTENS SOUTH OF AN AREA OF LOW PRESSURE PASSING NORTH
OF THE FORECAST AREA. GUSTS IN THE 25-30 KT RANGE ARE LIKELY
FROM LATE MORNING THROUGH THE AFTERNOON HOURS, BEFORE
DIMINISHING QUICKLY WITH SUNSET. A WEAK COLD FRONT TRAILING THE
AFOREMENTIONED LOW PRESSURE SYSTEM IS EXPECTED TO SAG INTO
NORTHEAST IL AFTER MIDNIGHT MONDAY NIGHT. ALTHOUGH THERE DOES
NOT APPEAR TO BE MUCH PUSH TO THE FRONT, AND TIMING REMAINS
SOMEWHAT UNCERTAIN, HAVE INDICATED A WIND SHIFT TO AN EASTERLY
DIRECTION FOR ORD/MDW PRIOR TO DAYBREAK TUESDAY. THERE IS SOME
INDICATION THAT LOWER CLOUDS AND POSSIBLY SOME LIGHT FOG MAY
PRODUCE A PERIOD OF MVFR CONDITIONS BEHIND THE FRONT.
IN THE SHORTER TERM, MODEL GUIDANCE HAS TRENDED AWAY FROM A
PERIOD OF IFR STRATUS AROUND DAYBREAK MONDAY. THERE IS STILL
SOME SIGNAL FOR SOME PATCHY IFR/LOW-MVFR CLOUDS AT THAT TIME,
THOUGH CONFIDENCE HAS DECREASED ENOUGH TO PULL THE TEMPO FOR
IFR WITH THIS FORECAST. IT IS MORE LIKELY THAT AN AREA OF FOG
WILL DEVELOP SOUTH OF THE TERMINALS (GENERALLY ALONG/SOUTH OF
THE I-80 CORRIDOR) PREDAWN. GYY LIKELY HAS THE GREATEST
POTENTIAL TO SEEM SOME FOG AND HAVE MAINTAINED A TEMPO FOR BR
AND BRIEF IFR CIG THERE.
RATZER
CLIMATE
ISSUED AT 913 PM CST SUN FEB 15 2026
RECORD WARMTH IS FORECAST ON MONDAY FEBRUARY 16TH, WITH HIGHS
INTO THE 60S.
HERE ARE THE CURRENT RECORD HIGHS FOR FEBRUARY 15TH FOR CHICAGO
AND ROCKFORD:
CHICAGO: 58 DEGREES IN 1921
ROCKFORD: 57 DEGREES IN 1921
NWS CHICAGO
LOT WATCHES/WARNINGS/ADVISORIES
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY FROM 9 AM TO 6 PM CST MONDAY FOR THE IL
AND IN NEARSHORE WATERS.
VISIT US AT WEATHER.GOV/CHICAGO
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