177
FXUS63 KGRB 031802
AFDGRB
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREEN BAY WI
102 PM CDT SAT OCT 3 2026
FORECAST DISCUSSION FOR ROUTINE AFTERNOON FORECAST ISSUANCE
KEY MESSAGES
- CHANCE OF SHOWERS (40 TO 90%) AT TIMES THROUGH LATE TONIGHT.
GREATEST CHANCES OF OVER 0.25 INCH OF RAIN FAR NORTH-CENTRAL WI.
OTHERWISE, MAINLY DRY THROUGH NEXT WEEK.
- AREAS OF FROST ACROSS NORTHERN WISCONSIN BOTH SUNDAY AND MONDAY
NIGHTS. GREATEST CHANCE FOR A WIDESPREAD FROST/FREEZE EVENT
WILL BE SUNDAY NIGHT.
DISCUSSION
ISSUED AT 101 PM CDT SAT OCT 3 2026
RAIN CHANCES THROUGH SUNDAY...WEAK WARM AIR ADVECTION HAS BEEN MAIN
TRIGGER FOR ISOLATED LIGHT SHOWERS SEEN SO FAR TODAY OVER WI.
EXPECT A FEW SHOWERS THROUGH LATE THIS AFTERNOON ESPECIALLY
NORTH-CENTRAL ON TAIL OF WAVE CROSSING LAKE SUPERIOR AND JUST
AHEAD OF WEAK ELEVATED INSTABILITY. THUNDER RISK DOES APPEAR TO
STAY CONFINED TO FAR WESTERN WI. BETTER PUSH FOR RAIN SHOWERS
MOVES THROUGH THIS EVENING AS SHORTWAVE TROUGH AND STRONGER
FORCING SLIDE THROUGH. DECENT AGREEMENT THAT NORTH-CENTRAL SEES
THE MOST RAIN BY DAYBREAK SUNDAY WITH OVER 0.25 INCH, BUT MAINLY
LESS THAN 0.50 INCH. THOUGH CHANCES HAVE INCREASED INTO SOUTH AND
EASTERN AREAS AS WELL LATE EVENING AND OVERNIGHT, THE RAIN AMOUNTS
WILL BE MOSTLY LESS THAN 0.15 INCH. RAIN SHIFTS EAST OF AREA AFTER
4A SUNDAY AS WEAK COLD FRONT MOVES THROUGH. NORTHWEST FLOW ACROSS
LAKE SUPERIOR COULD SQUEEZE A FEW SPRINKLES OUT OVER FAR NORTH
FROM A SHALLOW STRATOCU DECK, BUT MARGINAL OVER-WATER INSTABILITY
AND SHALLOW MOISTURE/LOW INVERSION HEIGHT WILL KEEP MAIN IMPACT
TO LINGERING CLOUDS IN THE MORNING. BY AFTERNOON, SKIES SHOULD
BECOME MOSTLY SUNNY, EVEN UP NORTH.
FROST/FREEZE POTENTIAL...AFTER A REPRIEVE FROM FROST/FREEZE ISSUES
TONIGHT DUE TO THE CLOUDS/RAIN MOVING THROUGH, ARRIVAL OF HIGH
PRESSURE RIDGE AND CLEARING LEADS TO ANOTHER ROUND OF FROST/FREEZE
SUNDAY NIGHT AND AGAIN MONDAY NIGHT, THEN AGAIN LATER THIS WEEK
OVER THE NORTH. FOR SUNDAY NIGHT, NBM SHOWING SIMILAR FOOTPRINT
TO WHAT OCCURRED THIS MORNING FOR TEMPS LESS THAN 36F, WITH A
40-80% CHANCE OF TEMPERATURES BELOW 33 OVER THE NORTHERN TIER OF
COUNTIES. GFS MOS GUIDANCE POINTS TO SUB-FREEZING TEMPS AS WELL.
MONDAY NIGHT PRETTY SIMILAR, THOUGH WITH CENTER OF HIGH SHIFTING
EAST, GREATEST RISK OF TEMPERATURES BELOW 33 IS SHUNTED TOWARD
FAR NORTHEAST WI, WITH LESS SIGNAL OVER NORTH-CENTRAL WI. EXPECT
ADDITIONAL FROST/FREEZE HEADLINES TO BE ISSUED FOR BOTH NIGHTS.
THOUGH NOT AS PRONOUNCED YET, ARRIVAL OF ANOTHER HIGH BRINGS MORE
POTENTIAL FOR FROST/FREEZE OVER FAR NORTH LATE THIS WEEK AS WELL.
EXTENDED...COLD FRONT COMES THROUGH ON WEDNESDAY, BUT LOOKS TOO
STARVED FOR MOISTURE TO PRODUCE ANY RAIN. SHARPER NORTHWEST FLOW
ALOFT AND STRONGER SHORTWAVE MAY DROP ACROSS LATE THIS WEEK, BUT
STRONGEST LIFTS PROBABLY STAYS NORTH RESULTING IN LREF SHOWING
LESS THAN 25% CHANCE OF SEEING EVEN A FEW HUNDREDTHS. MAYBE A BIT
BETTER SHOT OF SOME RAIN BEYOND NEXT WEEKEND PER LREF AND AI
GUIDANCE, BUT OVERALL AS MID SHIFT SAID, THE LONGER WE GO WITHOUT
SIGNIFICANT RAIN, WE COULD START TO HAVE INCREASING FIRE WEATHER
CONCERNS OVER THE NEXT SEVERAL WEEKS DUE TO CURRENT DROUGHT STATUS
AND INCREASING FINE FUELS AS WE EXPERIENCE REPEATED FROST/FREEZE
CONDITIONS.
AVIATION
FOR 18Z TAF ISSUANCE
ISSUED AT 101 PM CDT SAT OCT 3 2026
MID CLOUDS FILTERING ACROSS THIS AFTERNOON COULD PRODUCE AN
ISOLATED LIGHT SHOWER OR SPRINKLE. MAIN PUSH OF SHOWERS MOVES
THROUGH THIS EVENING INTO THE OVERNIGHT. EVEN DURING THE RAIN
THOUGH, CONDITIONS WILL STAY MAINLY VFR. LATE TONIGHT AS RAIN
ENDS, APPEARS LOWER MVFR CIGS DEVELOP NORTH-CENTRAL (RHI) WITH
SCATTERED MVFR CU/STRATOCU ELSEWHERE. MVFR CIGS NORTH-CENTRAL
LIFT TO VFR BY MIDDAY ON SUNDAY, WITH ALL AREAS BECOMING MOSTLY
CLEAR ON SUNDAY AFTERNOON.
WINDS WILL BE MAINLY OUT OF THE SOUTH THROUGH THIS EVENING,
GUSTING UP TO 22 KNOTS AT TIMES. WINDS THEN VEER NORTHWESTERLY BY
SUNDAY MORNING, STAYING GUSTY INTO THE AFTERNOON. BRIEF LLWS MAY
IMPACT RHI THIS EVENING.
MARINE
ISSUED AT 101 PM CDT SAT OCT 3 2026
INCREASING SOUTHERLY WINDS INTO THIS EVENING WILL RESULT IN
CONDITIONS HAZARDOUS TO SMALL CRAFT DEVELOPING ALONG THE
NEARSHORE WATERS OF LAKE MICHIGAN INTO EARLY THIS EVENING, AND
LASTING INTO SUNDAY MORNING. SOUTHWEST WINDS WILL GUST TO 25
KNOTS, WITH WAVES BUILDING TO 4 TO 6 FT, HIGHEST NEAR DEATH'S
DOOR AND THE LAKE SIDE OF WASHINGTON ISLAND.
GRB WATCHES/WARNINGS/ADVISORIES
NONE.
DISCUSSION.....JLA
AVIATION.......JLA
MARINE.........JLA
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