270
FXUS63 KLOT 281956
AFDLOT
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHICAGO/ROMEOVILLE, IL
256 PM CDT FRI MAR 28 2025
KEY MESSAGES
- WINDY AND WARM WITH SOUTHWEST WINDS GUSTING TO AROUND 40 MPH
THROUGH THIS EVENING.
- A COLD FRONT WILL MOVE SOUTH INTO NORTHERN IL SATURDAY
AFTERNOON, TURNING TEMPS MUCH COOLER NEAR LAKE MICHIGAN.
- SCATTERED SHOWERS AND A FEW STORMS ARE POSSIBLE SATURDAY
AFTERNOON AND NIGHT.
- STRONG TO SEVERE STORMS WILL BE POSSIBLE SUNDAY AS A LOW
PRESSURE SYSTEM TRACKS THROUGH THE UPPER-MISSISSIPPI RIVER
VALLEY.
- ACTIVE WEATHER PATTERN CONTINUES NEXT WEEK, WITH THE POTENTIAL
FOR 2 ADDITIONAL STORM SYSTEMS MODELED AT THE MIDDLE AND END
OF NEXT WEEK.
DISCUSSION
ISSUED AT 256 PM CDT FRI MAR 28 2025
THROUGH SATURDAY NIGHT:
A COMPACT WAVE INTERACTING WITH A SHALLOW LAYER OF MID-LEVEL
MOISTURE RESULTED IN HIGHER CLOUD AND SHOWER COVERAGE ACROSS
MUCH OF THE CENTRAL AND SOUTHERN CWA THROUGH EARLY AFTERNOON.
THIS DELAYED MIXING/WARMING AND STRONGER WINDS BY A FEW HOURS,
BUT RECENT OBS TRENDS INDICATE THE FORECAST IS MOSTLY BACK ON
TRACK WITH TEMPS IN THE MID TO UPPER 70S AND SOUTHWEST GUSTS TO
40-45 MPH (ESPECIALLY TOWARD CENTRAL ILLINOIS OVER THE NEXT FEW
HOURS).
A 60 KNOT LLJ DEVELOPING OVER THE FORECAST AREA THIS EVENING
WILL MAINTAIN GUSTY CONDITIONS WELL AFTER SUNSET. WITH ONLY
SOME MID/UPPER-LEVEL CLOUDS FILTERING OVER THE AREA, THERE MAY
BE SUFFICIENT NEAR-SURFACE STABILITY TO WARD OFF THE STRONGEST
GUSTS FROM REACHING THE SURFACE. HAVE THEREFORE HELD OFF ON A
WIND ADVISORY THROUGH THIS EVENING, BUT CANNOT RULE OUT A
RESURGENCE OF GUSTS OVER 40 MPH FOR A FEW HOURS DURING THE MID-
EVENING.
A STRONG LOW-LEVEL BAROCLINIC ZONE DRAPED ACROSS CENTRAL
WISCONSIN WILL REMAIN MOSTLY STATIONARY THROUGH THIS EVENING AS
A WEAK SURFACE LOW SHIFTS ALONG IT TO THE EAST. THIS WILL FORCE
A COLD FRONT TOWARD NORTHERN ILLINOIS THROUGH THE DAY ON
SATURDAY. HAVE CONTINUED TO LEAN ON GUIDANCE (HRRR/3KM NAM) THAT
PRODUCES A STRONGER AND FASTER SURGE OF THE FRONT INTO
NORTHEAST ILLINOIS DURING THE AFTERNOON AND EARLY EVENING, WITH
THE FRONT STALLING AROUND THE I-80 CORRIDOR SATURDAY NIGHT.
BEHIND THE FRONT, TEMPS WILL PLUMMET FROM AROUND 70 TO THE 40S
AND BE ACCOMPANIED BY SOME FOG AND DRIZZLE OR LIGHT RAIN.
ELSEWHERE, MOST OF THE FORECAST AREA WILL REMAIN IN A LULL IN
DYNAMICS AND PRECIP THROUGH THE DAY SATURDAY AND WELL INTO
SATURDAY NIGHT, WITH GENERALLY CLOUDY SKIES AND SOME SPOTTY
SHOWERS OR DRIZZLE. THE ONE EXCEPTION WILL BE EAST OF I-57
WHERE A CONVECTIVELY-ENHANCED WAVE CROSSING INDIANA BRINGS
SCATTERED SHOWERS AND PERHAPS A FEW STORMS LATE MORNING INTO
EARLY EVENING.
KLUBER
SUNDAY THROUGH FRIDAY:
THE APPROACHING LOW PRESSURE SYSTEM WILL LIFT WARM, MOIST AIR
INTO THE REGION THROUGHOUT SUNDAY MORNING AS THE WARM FRONT
LIFTS ACROSS NORTHERN ILLINOIS. THIS WILL INCREASE THE
POTENTIAL FOR STRONG TO SEVERE STORMS DURING THE AFTERNOON AND
EVENING. MUCAPE VALUES INCREASE SUNDAY MORNING ACROSS THE AREA,
RISING INTO THE 1000-1500 J/KG RANGE BY MIDDAY WITH THE CHANCE
UPWARDS OF 2000 J/KG ACROSS THE FAR SOUTHERN CWA. BETTER
INSTABILITY FACTORS WILL OCCUR WELL TO THE SOUTH OF OUR AREA,
HOWEVER THE CAPE ALONG WITH THE CLOSE PROXIMITY OF THE LOW CORE
SHOULD ALLOW FOR STORM DEVELOPMENT AHEAD OF THE FRONT DURING THE
AFTERNOON INTO THE EVENING. SPC HAS A LEVEL 3 OUT OF 5 ROUGHLY
SOUTH OF THE I-80 CORRIDOR, WITH A 2 OUT OF 5 TO THE NORTH. THE
VERTICAL WIND PROFILE OF THIS SYSTEM AS IT TRACKS THROUGH THE
REGION WILL BE FAIRLY UNIFORM, WHICH SHOULD ALLOW FOR STORMS TO
TRACK FROM THE WSW TO ENE. CANNOT RULE OUT TORNADO POTENTIAL,
BEING IN CLOSE PROXIMITY TO THE LOW CORE, HOWEVER THE BEST
THREAT AT THIS TIME APPEARS TO BE WIND. WITH THE INCREASE IN
WIND INDICATORS, THIS COULD ALSO RESULT IN MORE OF A BOWING LINE
OR SEGMENTS WHICH WOULD HAVE THE POTENTIAL OF PRODUCING QLCS
TORNADOES. WILL CONTINUE TO MONITOR THIS SYSTEM WITH FURTHER
UPDATES.
THE MAIN TROF AXIS PUSHES THROUGH THE REGION SUNDAY NIGHT, WHERE
THERE COULD BE SOME LINGERING PRECIPITATION TRYING TO SLIDE DOWN
FROM THE NORTH EARLY MONDAY. A SMALL CHANCE FOR SNOWFALL, WHICH
COULD LEAD TO SLUSHY ACCUMULATIONS, HOWEVER THE MAIN THOUGHT IS
THAT MAJORITY WOULD REMAIN LIQUID RAIN. DRIER CONDITIONS WILL
MOVE BACK INTO THE MIDWEST FOR THE FIRST PART OF NEXT WEEK, AS A
HIGH PRESSURE RIDGE TAKES OVER...ALTHOUGH TEMPERATURES WILL BE
LIMITED BY STRONG NORTHWEST AIRFLOW INTO THE REGION MONDAY
TURNING MORE EASTERLY OFF THE LAKE AND INTERIOR INDIANA TUESDAY.
ANOTHER WEATHER SYSTEM IS FORECAST TO TRACK THROUGH THE REGION
WEDNESDAY, WITH CURRENT MODEL GUIDANCE SHOWING A POTENTIAL FOR
A ROUGHLY SIMILAR TRACK TO SUNDAY'S SYSTEM. SOME EARLY
INDICATIONS WITH THE MID-WEEK SYSTEM POINT TO THE POTENTIAL OF
STRONG TO SEVERE STORMS AGAIN, HOWEVER WITH IT BEING SO FAR OUT,
THERE LIKELY WILL BE CHANGES OVER THE NEXT COUPLE OF DAYS SO
STAY TUNED FOR MORE UPDATES WITH THIS SYSTEM. A BREAK COMES
AROUND THURSDAY, HOWEVER SHORT LIVED, AS THE ACTIVE PATTERN
CONTINUES INTO THE END OF NEXT WEEK AND EARLY NEXT WEEKEND.
BAKER/KLUBER
AVIATION /18Z TAFS THROUGH 00Z SUNDAY/
ISSUED AT 1249 PM CDT FRI MAR 28 2025
KEY AVIATION MESSAGES FOR THE CURRENT TAF PERIOD:
- SCATTERED SHOWERS ENDING AND MOVING EAST OF THE REGION EARLY
THIS AFTERNOON
- STRONG SOUTHWESTERLY WIND GUSTS AROUND 35 KNOTS THIS
AFTERNOON
- PERIOD OF LLWS TONIGHT AND INTO EARLY SATURDAY MORNING
- A FRONT MOVES DOWN THE LAKE SATURDAY AFTERNOON SWITCHING
WINDS TO THE NORTHEAST WITH THE CHANCE FOR SOME POST-FRONTAL
RAIN
SCATTERED SHOWERS PERSIST EARLY THIS AFTERNOON. THE GOOD NEWS
IS, THE NORTHERN BOUNDARY OF THE SHOWERS WILL CONTINUE TO
ERODE WHICH WILL RESULT IN MOSTLY DRY TAFS FROM CHICAGO TO
ROCKFORD. HOWEVER, THERE IS ANOTHER BOUNDARY THAT IS SLOWLY
MOVING NORTHWARD THAT IS KEEPING AN AREA OF CONVERGENCE WHERE
SCATTERED SHOWERS WILL PERSIST FOR THE NEXT HOUR. WHILE THERE
IS LOWER CONFIDENCE ON THE EXACT END TIME TO THE SHOWERS, DRIER
CONDITIONS ARE EXPECTED THIS AFTERNOON.
THE MAIN AVIATION IMPACT THIS AFTERNOON WILL BE FROM THE STRONG
SOUTHWESTERLY WIND GUSTS BEHIND THE PREVIOUSLY MENTIONED
BOUNDARY MOVING NORTH. THE STRONGEST GUSTS IN THE TAF WERE
CAPPED AROUND 35 KNOTS, BUT ISOLATED BURSTS UP TO 40 KNOTS ARE
CERTAINLY POSSIBLE (AND ALREADY OBSERVED AT DNV AND CMI).
WIND GUSTS WILL SLOWLY FALL UNDER 30 KNOTS AFTER 00Z. BUT
SHORTLY THEREAFTER, A STRONG LOW LEVEL JET WILL INCREASE TO 55
TO 60 KNOTS AROUND 2000 FEET OFF THE DECK. IT IS ANTICIPATED
THAT SURFACE WIND GUSTS WILL FALL TO THE LEVEL THAT WOULD
CREATE A PERIOD OF LLWS AT AREA TERMINALS OVERNIGHT.
WINDS WILL REMAIN OUT OF THE SOUTHWEST WITH GUSTS BETWEEN 20 TO
25 KNOTS THROUGH THE DAY ON SATURDAY. THERE IS A SLIGHT (20
PERCENT) CHANCE FOR SOME LIGHT SHOWERS TO MOVE IN AROUND GYY IN
THE LATE MORNING/EARLY AFTERNOON, BUT IT WAS KEPT OUT OF THE TAF.
HOWEVER, AT THE END OF THE TAF PERIOD, A FRONT IS EXPECTED TO
MOVE DOWN THE LAKE WHICH WILL CAUSE THE WINDS TO FLIP AROUND TO
THE NORTHEAST, LEAD TO LOWER CIGS AND A CHANCE FOR RAIN.
DK
MARINE
ISSUED AT 256 PM CDT FRI MAR 28 2025
- GALE WARNING REMAINS IN EFFECT FOR THE ILLINOIS AND PORTIONS
OF THE NORTHWEST INDIANA NEARSHORE WATERS OF LAKE MICHIGAN
THROUGH THIS EVENING.
GALE FORCE GUSTS IN EXCESS OF 35 KNOTS WILL CONTINUE THROUGH
THIS EVENING, WITH A PERIOD OF GUSTS SURPASSING 40 KNOTS AT THE
HIGHER PLATFORMS THIS EVENING. SINCE WATER TEMPERATURES REMAIN
COLD (LEADING TO STABILITY OVER THE LAKE), THE THREAT FOR GALE
FORCE WINDS WILL BE WITHIN THE FIRST FEW MILES OF THE LAKESHORE.
NWS CHICAGO
LOT WATCHES/WARNINGS/ADVISORIES
IL...NONE.
IN...NONE.
LM...GALE WARNING UNTIL 3 AM CDT SATURDAY FOR THE IL AND IN
NEARSHORE WATERS.
VISIT US AT WEATHER.GOV/CHICAGO
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page