303
FXUS63 KGRB 081705
AFDGRB
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREEN BAY WI
1205 PM CDT THU OCT 8 2026
UPDATED AVIATION PORTION FOR 18Z TAF ISSUANCE
KEY MESSAGES
- GUSTY WEST-NORTHWEST WINDS OF 25 TO 30 MPH WILL DEVELOP THIS
AFTERNOON.
- PATCHY FROST WILL DEVELOP EARLY FRIDAY MORNING ACROSS PARTS OF
NORTH-CENTRAL AND FAR NORTHEAST WISCONSIN AS LOW TEMPERATURES
FALL INTO THE 34 TO 37 DEGREE RANGE.
- UNSEASONABLY WARM AND WINDY CONDITIONS ARRIVE SATURDAY AND SUNDAY
WITH INLAND HIGH TEMPERATURES INTO THE UPPER 70S TO LOWER 80S.
- RAIN SHOWER CHANCES INCREASE TO 40 TO 50 PERCENT MONDAY
AFTERNOON THROUGH MONDAY NIGHT AS A COLD FRONT CROSSES
WISCONSIN. MUCH COOLER TEMPERATURES IN THE 50S WILL FOLLOW FOR
TUESDAY AND WEDNESDAY.
DISCUSSION
ISSUED AT 1059 PM CDT WED OCT 7 2026
THE CURRENT SURFACE ANALYSIS SHOWS WISCONSIN POSITIONED BETWEEN
SURFACE HIGH PRESSURE BUILDING OVER THE NORTHERN PLAINS AND A COLD
FRONT SHIFTING ACROSS THE EASTERN GREAT LAKES. THIS HIGH PRESSURE
SYSTEM WILL SLOWLY SETTLE OVER THE WESTERN GREAT LAKES OVER THE
NEXT 24 HOURS. BROAD SUBSIDENCE AND LIGHT WINDS WILL YIELD
GENERALLY QUIET WEATHER ACROSS NORTH- CENTRAL AND NORTHEAST
WISCONSIN THROUGH FRIDAY.
GUSTY NORTHWEST WINDS THURSDAY: A TIGHT SURFACE PRESSURE GRADIENT
COMBINED WITH STEEP BOUNDARY LAYER LAPSE RATES WILL DRIVE GUSTY
NORTHWEST WINDS ACROSS THE REGION AGAIN ON THURSDAY. MOMENTUM
TRANSFER FROM 850MB WIND PROFILES AROUND 25 TO 30 KNOTS WILL
SUPPORT SURFACE WIND GUSTS OF 25 TO 30 MPH ACROSS CENTRAL AND
NORTHEAST WISCONSIN DURING THURSDAY AFTERNOON. WINDS WILL QUICKLY
DECOUPLE AND DIMINISH THURSDAY EVENING AS THE SURFACE HIGH
PRESSURE CENTER SETTLES DIRECTLY OVER WISCONSIN.
PATCHY FROST LATE THURSDAY NIGHT: HIGH PRESSURE CENTERED OVER
WISCONSIN THURSDAY NIGHT WILL PROMOTE DECOUPLING WINDS WHICH IS
FAVORABLE FOR FROST. HOWEVER, SOME INDICATIONS OF MID AND HIGH
CLOUDS OVERHEAD FOR LARGE PORTIONS OF THE NIGHT. THIS LEADS TO
LOWER CONFIDENCE FOR ISSUING A FROST ADVISORY DESPITE NBM GUIDANCE
SHOWING A 50 TO 90 PERCENT PROBABILITY OF TEMPERATURES FALLING
BELOW 37 DEGREES ACROSS THE NORTHWOODS, WITH LAND O LAKES AND
CRANDON REACHING NEAR THE FREEZING MARK. WILL LET THE NEXT SHIFT
TAKE ANOTHER LOOK BEFORE ISSUING A FROST ADVISORY ACROSS VILAS,
ONEIDA, LINCOLN, FOREST, FLORENCE, AND NORTHERN MARINETTE
COUNTIES. HIGH CONFIDENCE EXISTS THAT MAX TEMPERATURES RECOVER
QUICKLY INTO THE UPPER 60S ON FRIDAY AFTERNOON.
UNSEASONABLE WEEKEND HEAT AND STRONG WINDS:
AS SURFACE HIGH PRESSURE SHIFTS TO THE EAST COAST, AN INTENSE
UPPER-LEVEL RIDGE WILL BUILD ACROSS THE WESTERN GREAT LAKES,
TRIGGERING ROBUST SOUTHERLY RETURN FLOW. DAYTIME HIGH TEMPERATURES
ON SATURDAY AND SUNDAY WILL CLIMB INTO THE UPPER 70S AND LOWER
80S ACROSS INLAND WISCONSIN, APPROACHING DAILY RECORD HIGH VALUES
AT SOME LOCATIONS. TIGHTENING REGIONAL PRESSURE GRADIENTS WILL
DRIVE GUSTY SOUTHERLY WINDS OF 30 TO 40 MPH, WITH NBM
PROBABILISTIC GUIDANCE INDICATING A 40 TO 60 PERCENT PROBABILITY
OF GUSTS EXCEEDING 35 MPH ON SATURDAY.
EARLY WEEK COLD FRONT AND COOL DOWN: A COLD FRONT ASSOCIATED WITH
A NORTHERN STREAM TROUGH WILL TRAVERSE WISCONSIN SUNDAY NIGHT
INTO MONDAY. RAIN CHANCES REMAIN ON TRACK TO DEVELOP POST FRONTAL
ON MONDAY AFTERNOON THROUGH MONDAY NIGHT. MID-LEVEL FRONTOGENESIS
WILL INCREASE 24-HOUR PRECIPITATION PROBABILITIES TO 40 TO 50
PERCENT AREA- WIDE, THOUGH DYNAMIC FORCING REMAINS PROGRESSIVE.
NBM PROBABILISTIC GUIDANCE INDICATES A 20 TO 30 PERCENT CHANCE OF
24-HOUR LIQUID ACCUMULATIONS EXCEEDING 0.25 INCHES, WITH EXPECTED
RAINFALL TOTALS GENERALLY UNDER A QUARTER INCH. POST-FRONTAL COLD
AIR ADVECTION WILL USHER IN A SIGNIFICANTLY COOLER AIRMASS FOR
TUESDAY AND WEDNESDAY, DROPPING DAYTIME HIGH TEMPERATURES BACK
INTO THE LOWER TO MID-50S UNDER PARTLY SUNNY SKIES.
AVIATION
FOR 18Z TAF ISSUANCE
ISSUED AT 1205 PM CDT THU OCT 8 2026
VFR CONDITIONS WILL PERSIST THROUGH THE TAF PERIOD. SCT HIGH CIRRUS
CLOUDS WILL CONTINUE TO PASS OVER THE REGION THROUGH THE PERIOD. A
SCT TO BKN CU FIELD, BASED AROUND 5-6KFT, IS DEVELOPING OVER
NORTHERN WI EARLY THIS AFTERNOON AND WILL LINGER INTO THIS EVENING
BEFORE SCATTERING OUT. WEST-NORTHWEST WINDS WILL GUST UP TO 20-25
KTS THIS AFTERNOON WITH WINDS DIMINISH WITH THE LOSS OF HEATING
AROUND SUNSET.
MARINE
ISSUED AT 1059 PM CDT WED OCT 7 2026
WHILE WINDS HAVE SUBSIDED THIS EVENING, WEST-NORTHWEST WINDS ARE
EXPECTED TO BECOME GUSTY AGAIN ON THURSDAY. GUSTS 20 TO 25 KTS ARE
EXPECTED ON THURSDAY AFTERNOON. SMALL CRAFT ARE URGED TO EXERCISE
CAUTION. AFTER A PERIOD OF LIGHT WINDS, SOUTH WINDS ARE FORECAST
TO INCREASE ON FRIDAY AND REMAIN STRONG AND GUSTY THROUGH THE
WEEKEND. WAVES ARE EXPECTED TO BUILD TO 3-6 FT ON LAKE MICHIGAN
FROM FRIDAY AFTERNOON THROUGH FRIDAY NIGHT. THEN SOUTH WINDS TO 30
KTS ON SATURDAY AND SATURDAY NIGHT. SMALL CRAFT ADVISORIES WILL
BE REQUIRED FROM FRIDAY NIGHT THROUGH SATURDAY NIGHT, AND PERHAPS
ON SUNDAY AS WELL.
GRB WATCHES/WARNINGS/ADVISORIES
NONE.
DISCUSSION.....MPC
AVIATION.......GK
MARINE.........MPC
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