019
FXUS63 KAPX 041053
AFDAPX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GAYLORD MI
653 AM EDT THU SEP 4 2025
KEY MESSAGES
- PERIODS OF LAKE EFFECT RAIN SHOWERS THROUGH THE NEXT SEVERAL DAYS
- GUSTY WINDS AND GALES LATE TONIGHT INTO FRIDAY
- COLD TEMPS HANG ON THROUGH THE WEEKEND
SHORT TERM /THROUGH TONIGHT/
ISSUED AT 414 AM EDT THU SEP 4 2025
PATTERN SYNOPSIS/FORECAST:
DEEP UPPER LOW SWIRLING OVER NORTHERN LAKE SUPERIOR ATTM (541DM AT
500MB), WITH STRONG NORTH TO NORTHWESTERLY FLOW IN ITS WAKE ACROSS
MUCH OF THE CENTRAL US/MIDWEST. PLUME OF MOISTURE ALONG THE
BAROCLINIC ZONE (AND IT IS VERY BAROCLINIC, WITH SURFACE TEMPS IN
THE 60S AHEAD OF IT...AND 40S BEHIND IT) FROM THE SURFACE LOW NEAR
JAMES BAY, DOWN THROUGH THE OH VALLEY INTO THE SOUTH CENTRAL PLAINS
AS A COLD FRONT. IT THEN WRAPS BACK NORTHWARD ALONG THE ROCKIES INTO
SASKATCHEWAN...WHERE ANOTHER SYSTEM IS IN THE WORKS WITH ANOTHER
STRONG PUNCH OF PV DROPPING OUT OF NORTH CENTRAL CANADA. COLD HIGH
PRESSURE OVER THE NORTHERN PLAINS ATTM...WITH BROAD AREA UNDER THE
INFLUENCE OF 0C ISOTHERM AT 850MB; -4C AT 850 IS JUST TO OUR NORTH
OVER ONTARIO.
ANOTHER LOBE OF PV SWINGS THROUGH EARLY TODAY, DRAGGING ANOTHER
SURFACE TROUGH ACROSS THE AREA. THIS SHOULD BE QUICK-
MOVING...ALREADY SWINGING ON OUT BY 18Z, THOUGH SOME SUBTLE NIBLETS
IN ITS WAKE COULD KEEP THINGS PERTURBED ENOUGH TO SQUEEZE OUT A
LITTLE MORE LAKE EFFECT RAIN THAN EXPECTED THIS AFTERNOON. FLOW TO
BACK MORE SOUTHWESTERLY TODAY...AHEAD OF ANOTHER PV MAXIMA DIGGING
INTO THE NORTHERN PLAINS TODAY. EXPECTATION IS FOR THIS TO PLOW
ACROSS MN AND WI TONIGHT, KNOCKING ON OUR DOOR BY EARLY FRIDAY
MORNING, WITH A STRENGTHENING SURFACE LOW TO BOOT...WHICH WILL BUMP
UP SOUTHWESTERLY FLOW EVEN MORE FOR TONIGHT INTO FRIDAY.
PRIMARY FORECAST CONCERNS THROUGH TONIGHT:
PERIODS OF LAKE EFFECT RAIN SHOWERS...EXPECT PERIODS OF LAKE EFFECT
RAIN SHOWERS TODAY AS NIBLETS PIVOT THROUGH...INITIALLY WEST-FLOW
ORIENTED, BUT BECOMING SOUTHWEST-FLOW ORIENTED AS WE GO INTO LATE
AFTERNOON AND TONIGHT AHEAD OF THE NEXT SYSTEM. WITH MOISTURE ALOFT
SNEAKING IN LATE TODAY/TONIGHT, DO HAVE TO WONDER IF IT WILL BE ABLE
TO SEEDER-FEEDER ANY BETTER RETURNS...THOUGH IT IS POSSIBLE THE MID-
LEVEL DRY LAYER COULD BE TOO FIRM TO DO MUCH TILL THE DEEPER
MOISTURE THROUGH THE COLUMN MOVES IN LATE. FOR NOW, EXPECTING
HIGHEST RAINFALL TOTALS ACROSS THE CENTRAL AND INTO EASTERN UP LATE
TONIGHT, WHICH ATTM APPEARS TO BE CLOSEST TO BEST FORCING FOR
LONGEST. DECENT SIGNALS IN PROBABILISTIC GUIDANCE AGAIN (40-50
PERCENT) OF AT LEAST AN INCH OF RAIN IN THIS REGION (POTENTIALLY IN
6-HRS) BY FRIDAY MID-MORNING. A FEW RUMBLES OF THUNDER AREN'T
IMPOSSIBLE, AS WE'LL BE COLD ENOUGH TO HAVE ICE NUCLEATION, BUT
NOTHING DRAMATIC BY ANY MEANS...THOUGH WITH WINDS ALOFT STAYING
GENERALLY WEAKER, WATERSPOUTS WILL REMAIN A THREAT INTO TONIGHT
BEFORE WINDS START TO BECOME TOO STRONG ALOFT IN ADVANCE OF THE NEXT
SYSTEM.
INCREASING WINDS...SOUTHWEST WINDS SHOULD START TO PICK UP LATE
TONIGHT, PARTICULARLY AFTER 6Z, AS THE LOW-LEVEL JET ALOFT SWIRLS IN
CLOSER. EXPECT THE FIRST GALES OF THE SEASON, AS WINDS ALOFT RAMP UP
TO 35-45KTS AT 850MB LATE TONIGHT. PROBABILISTIC WIND GUIDANCE
SUGGESTS HIGH CONFIDENCE IN WINDS 25-35KTS LATE TONIGHT INTO FRIDAY
MORNING; LOW BUT NON-ZERO POTENTIAL FOR GUSTS OVER 40-45KTS DURING
THE EARLY MORNING HOURS, PARTICULARLY NEAR THE LAKE MICHIGAN WHERE
FRICTION WILL BE MINIMIZED. LOW PRESSURE SHOULD BE A QUICK HITTER,
ALREADY SWINGING NORTHEASTWARD BY LATE MORNING/MIDDAY...WHICH IN
THEORY SHOULD ALLOW GALES TO WIND DOWN ON THE LAKE MICHIGAN
WATERS/COAST A BIT QUICKER THAN POINTS EASTWARD...WHICH SHOULD HOLD
ONTO STRONGER WINDS LATER IN THE DAY AHEAD OF THE FRONT.
LONG TERM /FRIDAY THROUGH WEDNESDAY/
ISSUED AT 414 AM EDT THU SEP 4 2025
DAYS 2-3 (FRIDAY-SATURDAY)...
LOBE OF PV AND ATTENDANT TIGHTLY-WOUND SURFACE LOW DRIVE ACROSS
NORTHERN MICHIGAN EARLY FRIDAY...LIFTING NORTHEASTWARD INTO ONTARIO
THROUGH THE DAY. WILL EXPECT STRONG SOUTHWEST WINDS AHEAD OF THE LOW
TO BECOME STRONG WEST TO NORTHWEST WINDS IN ITS WAKE FRIDAY
AFTERNOON. PARADE OF PV MAXIMA THEN LOOK TO SWIRL AROUND THE
PERIMETER OF LONGWAVE TROUGHING THROUGH THE UPPER MIDWEST AND GREAT
LAKES FRIDAY NIGHT THROUGH SATURDAY NIGHT...KEEPING THINGS UNSETTLED
THROUGH THE END OF THE WEEK.
STRONG WINDS CONTINUE FRIDAY...SOME 30+KT WINDS COULD MIX DOWN TO
THE SURFACE OVER LAND AS WELL DURING THE MORNING IN PARTICULAR...ON
TOP OF SUSTAINED WINDS LIKELY RUNNING 15-25KTS, HIGHEST CLOSEST TO
THE COAST. NOT IMPOSSIBLE SOME AREAS COULD END UP WITH A WIND
ADVISORY, AS IT WILL BE CLOSE...AND AS MENTIONED ABOVE, THERE IS LOW
BUT NON-ZERO POTENTIAL FOR GUSTS AS HIGH AS 45KTS NEAR THE LAKE
MICHIGAN COAST DURING THE MORNING HOURS. AS FOR THE SUNRISE SIDE AND
LAKE HURON COAST...CURRENTLY THINK THE STRONGEST WINDS WILL HOLD OFF
TILL CLOSER TO 12Z OR LATER. WILL BE SOMETHING TO WATCH CLOSELY,
THOUGH, AS THERE IS STILL A BIT OF FINE TUNING OF THE LOW TRACK TO
BE HAD, WHICH COULD IMPACT THE POSITION/TIMING OF THE STRONGEST
WINDS.
DAYS 4-7 (SUNDAY-WEDNESDAY)...
ATTM...APPEARS LAST LOBE OF PV SWINGS THROUGH SUNDAY...WITH RISING
HEIGHTS GENERALLY EXPECTED GOING INTO LATE SUNDAY/SUNDAY NIGHT,
THOUGH UPPER LOW TRIES TO MAKE ONE LAST GRAB FOR THE EUP AS IT HEADS
EASTWARD GOING INTO MONDAY. SURFACE HIGH PRESSURE SHOULD GENERALLY
BE ON THE INCREASE FOR THE START OF NEXT WEEK, WHICH HAS POTENTIAL
TO LEAD TO SOME RADIATIONAL COOLING AND FROST/FREEZE POTENTIAL FOR
ANY AREAS THAT MANAGE TO BREAK OUT OF THE LAKE-INDUCED CLOUD COVER.
WE MAY ACTUALLY HAVE A BREAK IN THE ACTION OVERALL MONDAY...WITH THE
EXPECTATION OF SOUTHWESTERLY FLOW PICKING UP ACROSS THE CENTRAL
US/MIDWEST GOING INTO MIDWEEK...AS RIDGING CURRENTLY LOOKS TO BUILD
EASTWARD TOWARD US THROUGH THE WEEK. THIS SUGGESTS POTENTIAL FOR US
TO TREND MORE TOWARD NORMAL AGAIN, TEMPERATURE WISE.
AVIATION /12Z TAFS THROUGH 12Z FRIDAY/
ISSUED AT 653 AM EDT THU SEP 4 2025
MAINLY VFR THRU THIS EVENING, WITH LIGHT LAKE EFFECT RAIN
SHOWERS POSSIBLE AT TIMES TODAY (MAINLY PLN). CHILLY AIR WILL
REMAIN IN THE AREA. SOME CU/STRATOCU WILL BE SEEN, BUT MAINLY
VFR. CONDITIONS WILL WORSEN LATE TONIGHT, AS AN INCOMING
REINFORCING COLD FRONT BRINGS SHOWERS, LOWER CIGS, AND WINDIER
CONDITIONS. MVFR CONDITIONS AT PLN/CIU VERY LATE TONIGHT. LLWS
POSSIBLE AT THE VERY TAIL END OF THE TAF AT TVC AND PERHAPS
OTHERS.
APX WATCHES/WARNINGS/ADVISORIES
MI...BEACH HAZARDS STATEMENT FROM 1 PM EDT THIS AFTERNOON THROUGH
THIS EVENING FOR MIZ016-099.
MARINE...GALE WATCH FROM LATE TONIGHT THROUGH FRIDAY AFTERNOON FOR
LHZ345>349.
GALE WARNING FROM 4 AM TO NOON EDT FRIDAY FOR LMZ323-341-342-
344>346.
SMALL CRAFT ADVISORY FROM 5 AM FRIDAY TO 1 AM EDT SATURDAY FOR
LSZ321-322.
SHORT TERM...FEF
LONG TERM...FEF
AVIATION...JZ
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