494
FXUS63 KMKX 220253 AAA
AFDMKX
AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE MILWAUKEE/SULLIVAN WI
953 PM CDT TUE OCT 21 2025
KEY MESSAGES
- SCATTERED SHOWERS GRADUALLY SHIFT INTO NORTHEAST HALF OF THE
AREA OVERNIGHT INTO WEDNESDAY. GUSTS OF 30 TO 35 MPH CONTINUE
DURING THIS TIME, HIGHEST CLOSER TO LAKE MICHIGAN.
- FROST/FREEZE POTENTIAL WEDNESDAY NIGHT, WITH FREEZE
CONDITIONS LIKELY THURSDAY NIGHT INTO FRIDAY MORNING.
UPDATE
ISSUED 953 PM CDT TUE OCT 21 2025
VARIOUS 500 MB VORTICITY MAXIMA CONTINUE TO ROTATE AROUND A 500
MB LOW, WHICH IS SLOWLY SHIFTING EAST OVERNIGHT INTO WEDNESDAY.
THIS PATTERN CONTINUES TO BRING MAINLY SCATTERED SHOWERS ACROSS
THE AREA, WITH MORE CONCENTRATED SHOWERS AT TIMES ROTATING
THROUGH.
AS THE UPPER LOW SHIFTS EAST OVERNIGHT INTO WEDNESDAY, THE
BACKSIDE OF THE SHOWERS SHOULD ALSO SHIFT EAST, WITH ISOLATED TO
SCATTERED SHOWERS (20 TO 30 PERCENT CHANCES) LINGERING OVER THE
NORTHEAST HALF OF THE FORECAST AREA. LOW CLOUDS SHOULD ALSO
LINGER INTO WEDNESDAY, WITH SOME BREAKS POSSIBLE IN FAR
SOUTHWEST PARTS OF THE AREA LATER ON WEDNESDAY.
THE PRESSURE GRADIENT WILL REMAIN TIGHT INTO WEDNESDAY, WITH
GUSTY WEST TO NORTHWEST WINDS EXPECTED. GUSTS UP TO 30 MPH TO
PERHAPS 35 MPH SHOULD OCCUR AT TIMES, HIGHEST CLOSER TO LAKE
MICHIGAN. LOWS TONIGHT SHOULD BE IN THE UPPER 30S TO LOWER 40S,
WITH HIGHS WEDNESDAY ONLY IN THE UPPER 40S TO AROUND 50 DEGREES.
WOOD
SHORT TERM
ISSUED 301 PM CDT TUE OCT 21 2025
TONIGHT THROUGH WEDNESDAY NIGHT:
GUSTY SOUTHWESTERLY WINDS WILL SHIFT TO BECOME GUSTY
NORTHWESTERLY WINDS BY THIS EVENING, WITH WIDESPREAD GUSTS UP TO
35 MPH EXPECTED. A FEW GUSTS TO 40 MPH ARE POSSIBLE ACROSS FAR
SOUTHERN WISCONSIN, WHERE A COMBINATION OF A 925-850 MB JET AND
STEEP LAPSE RATES WOULD ALLOW FOR MIXING OF MOMENTUM DOWN TO THE
SURFACE. THE MOST SIGNIFICANT JET DYNAMICS WILL EXIT LATE
TONIGHT, BRINGING AN END TO THE 40 MPH POTENTIAL. HOWEVER, STEEP
LAPSE RATES WILL REMAIN, WITH WINDS REMAINING GUSTY AROUND 30-35
MPH THROUGH THE OVERNIGHT HOURS. AS LOW PRESSURE SLOWLY EXITS
INTO ONTARIO, EXPECT WINDS TO GRADUALLY DIMINISH WEDNESDAY
AFTERNOON INTO WEDNESDAY NIGHT.
WIDESPREAD SHOWERS WILL CONTINUE THROUGH THIS EVENING.
LIGHTNING CHANCES HAVE BEEN REDUCED GREATLY, WITH ONLY ~10%
CHANCE OF A BOLT NEAR LAKE MICHIGAN THIS EVENING AS THE COLD
FRONT MOVES THROUGH AND POTENTIALLY IS ENHANCED BY WARM LAKE
MICHIGAN WATERS. SHOWERS WILL BECOME MORE SCATTERED IN NATURE
BEHIND THE FRONT, AND WILL SLOWLY TAPER OFF FROM SOUTHWEST TO
NORTHEAST AS LOW PRESSURE LIFTS NORTHWARD TONIGHT. ISOLATED TO
SCATTERED SHOWERS (20-40% CHANCE) THEN CONTINUE INTO WEDNESDAY
FROM CENTRAL WISCONSIN TO SOUTHEASTERN WISCONSIN. SHOWERS WILL
END INTO WEDNESDAY NIGHT AS WINDS TAPER OFF.
WEDNESDAY NIGHT, EXPECT CLEARING SKIES, SLOWING WINDS, AND
TEMPERATURES FALLING INTO THE 30S. SOUTHWESTERN WISCONSIN LOOKS
TO DIP INTO THE 30 TO 33 DEGREE RANGE, BRINGING POTENTIAL FOR A
FREEZE. ELSEWHERE, FROST IS POSSIBLE WITH TEMPERATURES IN THE
MID-30S. NEAR LAKE MICHIGAN WHERE CLOUD COVER LINGERS,
TEMPERATURES WILL REMAIN IN THE UPPER 30S AND PREVENT
FROST/FREEZE DEVELOPMENT.
MH
LONG TERM
ISSUED 301 PM CDT TUE OCT 21 2025
THURSDAY THROUGH TUESDAY:
THE UPPER LOW WILL CONTINUE TO SIT OVER CENTRAL QUEBEC ONE MORE
DAY THU. A SMALLER LOBE OF VORTICITY WILL SWING ACROSS FAR EASTERN
ONTARIO, WHICH WILL KEEP THE NORTHWEST WINDS BRISK OVER SOUTHEAST
WI AND ESPECIALLY OVER LAKE MICHIGAN. GUSTS DO NOT LOOK AS HIGH AS
THE PREVIOUS DAYS THOUGH, AND THE CHANCE FOR SHOWERS SHOULD REMAIN
OFFSHORE OF SOUTHEAST WI, ALTHOUGH A FEW COULD CLIP THE SHORELINE
THU AFTERNOON.
CLEAR SKIES AND LIGHTER WINDS WILL ALLOW THE LOW TEMPERATURE FOR
THE LAKESHORE COUNTIES TO FALL INTO THE LOWER 30S THU NT, AND THUS
WILL LIKELY GET FROST. INLAND AREAS TOWARD CENTRAL WI HAVE A RISK
FOR A HARD FREEZE. MOST OF SOUTHERN WI IS EXPECTED TO DROP BELOW
30 DEGREES.
THE UPPER LOW WILL FINALLY MOVE OUT OF THE GREAT LAKES REGION
FRIDAY AND WEAK RIDGING ALOFT WILL MOVE IN. SURFACE HIGH PRESSURE
WILL ONLY STICK AROUND FOR FRIDAY AND FRIDAY NIGHT, BUT
TEMPERATURES WILL ALREADY BE REBOUNDING. HIGHS FRIDAY WILL BE IN
THE MID TO UPPER 50S AND LOWS FRI NT WILL GENERALLY BE ABOVE 32
DEGREES.
CLOUDS AND A SOUTHERLY BREEZE WILL RETURN TO SOUTHERN WI ON
SATURDAY AS A WEAK SHORTWAVE TROUGH DROPS THROUGH NORTHERN WI. THE
12Z GFS INTRODUCES A CHANCE FOR SHOWERS ALL THE WAY DOWN INTO
MARQUETTE TO SHEBOYGAN COUNTIES MIDDAY SATURDAY. HOWEVER, THE
ECMWF WEAKENS THE TROUGH QUICKER THAN THE GFS AND THEREFORE KEEPS
US DRY. ENSEMBLES KEEP THE AREA FAIRLY DRY, WITH LESS THAN A 20
PERCENT CHANCE. THIS WILL BE SOMETHING TO KEEP AN EYE ON FOR LATER
FCST UPDATES.
A CLOSED UPPER LOW WILL SLOWLY MAKE ITS WAY ACROSS THE SOUTHWEST
US OVER THE NEXT SEVERAL DAYS AND MAKE IT INTO THE MID MISSISSIPPI
RIVER VALLEY ON SUNDAY. THE GFS AND ECMWF DIFFER ON HOW THEY
HANDLE IT AFTER THIS POINT. THE GFS ABSORBS IT INTO AN UPPER
TROUGH APPROACHING FROM THE NORTHERN PLAINS, AND THE EC KEEPS IT
SEPARATE. THEREFORE, THERE IS A SMALL CHANCE FOR SHOWERS (15 TO
20%) IN THE CURRENT FORECAST FOR SRN WI ON SUNDAY, BUT ENSEMBLES
ARE SHOWING A SHIFT TOWARD MONDAY FOR THOSE CHANCES.
THAT NORTHERN PLAINS UPPER TROUGH WILL BE OUR NEXT WEATHER MAKER
FOR TUE-WED NEXT WEEK. THE EVOLUTION OF THE SURFACE LOW OVER THE
MIDWEST IS STILL VERY UNCERTAIN AND WILL BE SOMETHING TO WATCH.
CRONCE
AVIATION
ISSUED 953 PM CDT TUE OCT 21 2025
SCATTERED SHOWERS CONTINUE TO ROTATE SOUTHEASTWARD ACROSS THE
AREA, WITH MORE CONCENTRATED SHOWERS AT TIMES. THE BACKSIDE OF
THE SHOWERS SHOULD ALSO SHIFT EAST, WITH ISOLATED TO SCATTERED
SHOWERS LINGERING OVER THE NORTHERN AND EASTERN PORTIONS OF THE
AREA, INCLUDING THE SHEBOYGAN, MILWAUKEE AND WAUKESHA TERMINALS.
MAY SEE LOCALLY REDUCED VISIBILITY TO 4 MILES OR SO WITHIN ANY
CONCENTRATED AREAS OF SHOWERS.
LOW CLOUDS WITH CEILINGS DROPPING DOWN TO 1000 TO 1500 FEET AGL
OVERNIGHT SHOULD ALSO LINGER INTO WEDNESDAY, WITH SOME BREAKS
POSSIBLE IN FAR SOUTHWEST PARTS OF THE AREA LATER IN THE DAY.
CEILINGS SHOULD RISE ABOVE 3000 FEET AGL WEDNESDAY EVENING.
GUSTY WEST TO NORTHWEST WINDS ARE EXPECTED OVERNIGHT INTO
WEDNESDAY. GUSTS UP TO 25 KNOTS TO PERHAPS 30 KNOTS SHOULD OCCUR
AT TIMES, HIGHEST CLOSER TO LAKE MICHIGAN. GUSTY NORTHWEST
WINDS WILL LINGER WEDNESDAY NIGHT.
WOOD
MARINE
ISSUED 953 PM CDT TUE OCT 21 2025
LOW PRESSURE AROUND 29.4 INCHES OVER EASTERN LAKE SUPERIOR WILL
CONTINUE TO MOVE INTO NORTHERN LAKE HURON OVERNIGHT AND INTO
SOUTHERN QUEBEC ON WEDNESDAY. WEST GALES WILL BECOME NORTHWEST
FOR OPEN WATERS AREAS SOUTH OF A LINE FROM TWO RIVERS WISCONSIN
TO MANISTEE MICHIGAN DURING THIS PERIOD. A GALE WARNING REMAINS
IN EFFECT UNTIL 7 PM CDT WEDNESDAY EVENING. WINDS SHOULD
GRADUALLY WEAKEN WEDNESDAY EVENING.
A SMALL CRAFT ADVISORY REMAINS IN EFFECT UNTIL 7 PM CDT
WEDNESDAY EVENING, FOR GUSTY WEST TO NORTHWEST WINDS OVER THE
NEARSHORE WATERS. WAVES WILL BUILD DURING THIS TIME TOWARD THE
OPEN WATERS.
SCATTERED SHOWERS INTO WEDNESDAY NIGHT AND PERHAPS THURSDAY
MORNING WILL BE CAPABLE OF PRODUCING ISOLATED WATERSPOUT
ACTIVITY ACROSS MUCH OF THE OPEN WATERS.
LIGHT NORTHWESTERLY WINDS ARE THEN EXPECTED THROUGH THE END OF
THE WEEK, AS HIGH PRESSURE AROUND 30.2 INCHES BUILDS IN FROM THE
NORTHERN GREAT PLAINS. WINDS BECOME LIGHT AND VARIABLE FRIDAY
NIGHT INTO SATURDAY, AS HIGH PRESSURE AROUND 30.4 INCHES SHIFTS
SOUTHEAST THROUGH THE REGION.
MH/WOOD
MKX WATCHES/WARNINGS/ADVISORIES
WI...NONE.
LM...GALE WARNING...LMZ080-LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-
LMZ777-LMZ779-LMZ868-LMZ870-LMZ872-LMZ874-LMZ876-LMZ878
UNTIL 7 PM WEDNESDAY.
SMALL CRAFT ADVISORY...LMZ643-LMZ644-LMZ645-LMZ646 UNTIL 7 PM
WEDNESDAY.
VISIT US AT WEATHER.GOV/MILWAUKEE
FOLLOW US ON FACEBOOK, X, AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSMILWAUKEE
WWW.X.COM/NWSMILWAUKEE
WWW.YOUTUBE.COM/NWSMILWAUKEE
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page