940
FXUS63 KMKX 311142
AFDMKX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MILWAUKEE/SULLIVAN WI
642 AM CDT FRI JUL 31 2026
KEY MESSAGES
- WIDESPREAD SHOWERS WILL SPREAD WEST TO EAST TODAY, CONTINUING
ACROSS THE REGION THROUGH SATURDAY. ISOLATED THUNDERSTORMS ARE
POSSIBLE, ESPECIALLY SOUTH OF I-94.
- PROBABILITIES OF OVER 1 INCH OF RAINFALL ARE MODERATE TO HIGH
(OVER 60%) ALONG AND SOUTH OF I-94, WHILE PROBABILITIES OF
OVER 2 INCHES ARE MODERATE (OVER 40%) IN SOUTHWESTERN
WISCONSIN. FLOODING OR SEVERE STORMS IS NOT CURRENTLY
EXPECTED.
- BREEZY ONSHORE WINDS WILL LEAD TO HIGH WAVES AND DANGEROUS
CURRENTS AT LAKE MICHIGAN BEACHES THIS WEEKEND. A BEACH
HAZARDS STATEMENT IS IN EFFECT FROM LATE TONIGHT THROUGH
SUNDAY NIGHT FOR ALL LAKE MICHIGAN BEACHES.
- NEXT CHANCES FOR THUNDERSTORMS TUESDAY NIGHT INTO WEDNESDAY.
UPDATE
ISSUED 642 AM CDT FRI JUL 31 2026
THE FORECAST IS ON TRACK FOR A WIDESPREAD RAINFALL FROM LATER
TODAY THROUGH SATURDAY. 1-3 INCHES OF RAIN IS FORECAST, LESS
TOWARD EAST CENTRAL WI.
LOW PRESSURE OVER SW MN WILL SLOWLY TRACK AND DEEPEN SEWD INTO
ERN IA BY THIS EVENING, THEN OCCLUDE WITH ITS UPSTREAM SHORTWAVE
TROUGH OVER CENTRAL IL TNT. WELL ORGANIZED LOW TO MID LEVEL
WARM, MOIST ADVECTION AND FRONTOGENESIS WILL SLOWLY SHIFT ACROSS
THE REGION. THE UPPER TROUGH AXIS WILL THEN FOLLOW ON SATURDAY.
A DEEP WARM LAYER OF 4-4.5 KM IS EXPECTED WITH MOIST ADIABATIC
LAPSE RATES AND PWATS OF 1.7-2.1 INCHES. THE CONSENSUS FOR
RAINFALL WOULD RANGE FROM 0.5-1.25 INCHES OVER EAST CENTRAL WI
TO 2-3 INCHES SW OF MADISON. CANNOT RULE OUT ISOLATED URBAN AND
SMALL STREAM FLOODING.
GEHRING
SHORT TERM
ISSUED 111 AM CDT FRI JUL 31 2026
TODAY THROUGH SATURDAY NIGHT:
WITH LOW PRESSURE DEEPENING IN THE CENTRAL PLAINS AND PWATS OF
1.5-2 INCHES PROGRESSING EASTWARD INTO THE UPPER MIDWEST TODAY,
ANTICIPATING THE DRIER AIRMASS THAT MAY SERVE AS AN INHIBITING
FACTOR FOR RAINFALL TO STAY ACROSS CENTRAL TO NORTHERN WISCONSIN,
ALLOWING FOR A STEADY RAIN TO PROGRESS THROUGH SOUTHERN WISCONSIN
STARTING MIDDAY TODAY. A FEW PERIODS OF THUNDER MAY BE POSSIBLE,
ESPECIALLY SOUTH OF I-94, AS LOW PRESSURE MAKES ITS APPROACH
THROUGH CENTRAL IOWA THIS AFTERNOON. HOWEVER, ELEVATED INSTABILITY
AROUND 100-500 J/KG AND STRONGER CONVECTION ACROSS ILLINOIS MAY
ALLOW FOR ISOLATED LIGHTNING EVEN OUTSIDE OF STORM DEVELOPMENT IN
THE STRATIFORM REGION. EXPECTING HIGHS IN THE MID 70S TO LOW 80S
AHEAD OF RAINFALL.
STEADY RAIN IS EXPECTED TO CONTINUE THROUGH THE OVERNIGHT HOURS
TONIGHT ALONG AND SOUTH OF I-94, WITH THE LIGHTNING THREAT
DIMINISHING AFTER SUNSET AS LOW PRESSURE SINKS FARTHER SOUTH AND
CONTINUES TO OCCLUDE, PUTTING SOUTHERN WISCONSIN FIRMLY WITHIN THE
COLD CONVEYER BELT ON THE NORTHERN SIDE OF THE LOW. AREAS NORTH OF
I-94 ARE EXPECTED TO SEE MORE SHOWERY ACTIVITY RATHER THAN STEADY
RAINFALL. PWATS REMAIN IN THE 1.5-2 INCH RANGE, WITH WARM CLOUD
LAYERS AS DEEP AS 14,000 FT. THIS MAY LEAD TO VERY EFFICIENT RAIN
PRODUCTION EVEN WITHOUT CONVECTIVE DEVELOPMENT. A FEW CONVECTIVE
ALLOWING MODELS ARE CALLING FOR ISOLATED POCKETS OF RAINFALL UP TO
5 INCHES OVER TODAY AND TONIGHT, BUT THESE ACCUMULATIONS WILL
DEPEND ON EXACTLY WHERE MULTIPLE ROUNDS OF RAINFALL TRAIN, AND IF
NO TRAINING SEGMENTS DEVELOP MOST AREAS WILL SEE 1-2 INCHES TOTAL.
PROBABILITIES OF OVER 1 INCH ARE MODERATE TO HIGH (OVER 60%)
ALONG AND SOUTH OF I-94, WHILE PROBABILITIES OF OVER 2 INCHES ARE
MODERATE (OVER 40%) IN SOUTHWESTERN WISCONSIN NEAR THE CENTER OF
THE LOW TRACK.
SATURDAY, ALTHOUGH LOW PRESSURE WILL OCCLUDE AND PROGRESS EASTWARD
INTO THE OHIO VALLEY, WRAP-AROUND SHOWER ACTIVITY WILL CONTINUE
THROUGH MUCH OF THE DAY. STILL NOT ANTICIPATING MUCH THUNDER WITH
THIS ACTIVITY AS THE ATMOSPHERE REMAINS STABLE IN THE COLD AIR
PORTION OF THE LOW. PWATS REMAIN HIGH. WITH OVERCAST SKIES,
EXPECTING HIGHS IN THE 70S. NORTHEASTERLY WINDS WILL CONTINUE TO
GUST AROUND 30 MPH THROUGH THE DAY AND INTO THE OVERNIGHT HOURS AS
THE LOW FINISHES OCCLUDING AND STACKING. RAINFALL/SHOWERS WILL
FINALLY TAPER OFF WEST TO EAST INTO THE EVENING AS LOW PRESSURE
SLOWLY PIVOTS SOUTHEASTWARD, WITH PWATS FALLING BELOW 1.5 INCHES
OVERNIGHT. OVERNIGHT LOWS AROUND 60 DEGREES ARE EXPECTED.
AS THE LOW APPROACHES TONIGHT, EXPECT EASTERLY WINDS TO INCREASE
TO GUST BETWEEN 20 AND 30 MPH. AS WINDS INCREASE, ONSHORE FLOW
WILL LEAD TO HIGH WAVES AND DANGEROUS CURRENTS ALONG LAKE MICHIGAN
BEACHES. WINDS TURN NORTHEASTWARD INTO SATURDAY AS LOW PRESSURE
EXITS INTO THE OHIO VALLEY, BUT WILL CONTINUE TO INCREASE TO GUST
30 TO 35 MPH. A HIGH SWIM RISK IS EXPECTED LATE TONIGHT THROUGH
SUNDAY AS LOW PRESSURE LINGERS OVER THE OHIO VALLEY AND
NORTHEASTERLY WINDS CONTINUE. A BEACH HAZARDS STATEMENT IS IN
EFFECT. STAY OUT OF THE WATER AND AWAY FROM DANGEROUS AREAS LIKE
PIERS AND BREAKWALLS!
MH
LONG TERM
ISSUED 111 AM CDT FRI JUL 31 2026
SUNDAY THROUGH FRIDAY:
HIGH SWIM RISK CONTINUES INTO SUNDAY. EXPECT CONTINUED
NORTHEASTERLY WINDS GUSTING 20-30 MPH AS LOW PRESSURE SLOWLY
EXITS. NO PRECIPITATION IS EXPECTED, WITH HIGHS IN THE MID TO
UPPER 70S. HIGH PRESSURE BUILDS IN SUNDAY NIGHT INTO MONDAY,
BRINGING LIGHT AND VARIABLE WINDS AND TEMPERATURES IN THE LOW 80S
FOR MONDAY.
LOW PRESSURE DEVELOPS IN THE CENTRAL PLAINS TUESDAY, WITH A
SHORTWAVE OVER ONTARIO SHOWING POTENTIAL FOR PHASING WITH THIS
LOW, AND BRINGING THE NEXT CHANCES FOR PRECIPITATION TO SOUTHERN
WISCONSIN TUESDAY NIGHT THROUGH WEDNESDAY AS THE RESULTANT SYSTEM
PROPAGATES EASTWARD (20-30%). HIGHS IN THE LOW TO MID 80S ARE
EXPECTED BOTH TUESDAY AND WEDNESDAY.
ACTIVE PATTERN PERSISTS THROUGH FRIDAY, WITH MULTIPLE SHORTWAVES
DEVELOPING OFF THE NORTHERN PORTIONS OF THE CENTRAL PLAINS LOW.
UNCERTAINTY REMAINS IN THE LONGER TERM PORTION OF THE FORECAST AS
MODEL SOLUTIONS DIVERGE, THEREFORE KEPT NBM POPS IN THE 15-25%
RANGE THURSDAY AND FRIDAY.
MH
AVIATION
ISSUED 642 AM CDT FRI JUL 31 2026
MVFR AND IFR CIGS WILL SLOWLY SPREAD WEST TO EAST ACROSS SRN WI
TODAY AND THIS EVENING AS THE RAINFALL MOVES EWD. CIGS OF
600-1900 FT WILL THEN PREVAIL LATE TNT-SAT WHILE THE RAIN WILL
CONTINUE. VSBYS WILL RANGE 2-5SM WITH THE RAIN.
GEHRING
MARINE
ISSUED 111 AM CDT FRI JUL 31 2026
HIGH PRESSURE AROUND 30.0 INCHES WILL LINGER OVER LAKE MICHIGAN
THROUGH THIS MORNING, WITH LOW PRESSURE OVER THE CENTRAL PLAINS
DEEPENING TO 29.6 INCHES AS IT MOVES INTO EASTERN IOWA THIS
EVENING. THIS WILL SHIFT WINDS TO EASTERLY OVERNIGHT TONIGHT.
SATURDAY, EXPECT WINDS TO SHIFT TO NORTHEASTERLY AS LOW PRESSURE
MOVES INTO THE OHIO VALLEY AND DEEPENS TO 29.5 INCHES. GUSTS TO 30
KT ARE EXPECTED SATURDAY AFTERNOON THROUGH SUNDAY AFTERNOON FOR
THE SOUTHERN TWO-THIRDS. AN ISOLATED GALE IS POSSIBLE SUNDAY
AFTERNOON AS LOW PRESSURE LIFTS INTO MICHIGAN. A SMALL CRAFT
ADVISORY IS IN EFFECT FOR SOUTHERN WISCONSIN NEARSHORE ZONES FROM
LATE TONIGHT INTO SUNDAY NIGHT DUE TO GUSTY WINDS AND BUILDING
WAVES. LOW PRESSURE WILL FINALLY EXIT INTO SUNDAY NIGHT WITH
WINDS DIMINISHING INTO MONDAY. HIGH PRESSURE RETURNS MONDAY INTO
TUESDAY, BRINGING LIGHT AND VARIABLE WINDS. TUESDAY NIGHT INTO
WEDNESDAY, SOUTHERLY WINDS BECOME DOMINANT AS A LOW PRESSURE
SYSTEM DEVELOPS IN THE PLAINS.
MH
MKX WATCHES/WARNINGS/ADVISORIES
WI...BEACH HAZARDS STATEMENT...WIZ052-WIZ060-WIZ066-WIZ071-
WIZ072...4 AM SATURDAY TO 1 AM MONDAY.
LM...SMALL CRAFT ADVISORY...LMZ643-LMZ644-LMZ645-LMZ646...4 AM
SATURDAY TO 1 AM MONDAY.
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