093  
FXUS63 KDTX 071910  
AFDDTX  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI  
310 PM EDT TUE OCT 7 2025  
   
KEY MESSAGES
 
 
- LINGERING SHOWERS OVER THE SOUTHERNMOST AREAS TAPER OFF EARLY THIS  
EVENING.  
 
- COOL AND DRY CONDITIONS LAST THROUGH THE END OF THE WEEK.  
 
- FROST IS POSSIBLE WEDNESDAY NIGHT AND THURSDAY NIGHT.  
 

 
   
DISCUSSION
 
 
SURFACE COLD FRONT IS BEGINNING TO PUSH SOUTH AND EAST OF THE AREA  
THIS AFTERNOON WITH ELEVATED PORTIONS OF THE FRONTAL SLOPE STILL  
LINGERING SOUTH OF A PORT HURON-HOWELL LINE. THIS SUPPORTS LINGERING  
SCATTERED LIGHT SHOWERS/DRIZZLE THROUGH THE FIRST HALF OF THE  
EVENING BEFORE THE SLOPE FULLY VACATES SE MI. IN ITS WAKE, STRONG  
HIGH PRESSURE DROPPING OUT OF NORTHERN CANADA EXPANDS ACROSS THE  
MIDWEST AND GREAT LAKES. NORTHERLY LOW LEVEL FLOW ALONG THE EASTERN  
FLANK OF THE HIGH COMBINED WITH UPPER TROUGHING SLIDING OVER THE  
CENTRAL GREAT LAKES SETS UP RESPECTABLE CAA WITH LOCAL 850MB TEMPS  
FALLING TO AROUND 0C (PLUS OR MINUS A DEGREE) FOR WEDNESDAY.  
RESULTANT HIGHS ONLY TOP OUT IN THE MID 50S TO LOWER 60S- COOLEST IN  
THE THUMB, FALLING SHORT OF THE MID 60S EARLY OCTOBER AVERAGES.  
COOLER AIRMASS WILL BE SUPPORTIVE OF MOISTURE FLUX OFF LAKE HURON  
HOWEVER FORECAST SOUNDINGS STILL SUGGEST ONLY A SHALLOW SATURATED  
LAYER BELOW THE SUBSIDENCE INVERSION CAPPING CONVECTIVE DEPTHS AT  
ONLY A FEW THOUSAND FEET, WHICH LIKELY ALLOWS STRATOCU DEVELOPMENT  
OVER THE EASTERN HALF OF THE CWA BUT SHOULD PRECLUDE ANY LIGHT  
RAIN/DRIZZLE.  
 
FAVORABLE RADIATIVE COOLING SETUP DEVELOPS OVERNIGHT WEDNESDAY AS  
THE HIGH CENTER DRIFTS OVER THE LOWER PENINSULA PROMOTING CLEARER  
SKIES AND LIGHT, IF ANY, WINDS. WITH SURFACE DEWPOINTS RANGING  
BETWEEN 32-34F, LOW TEMPS WILL FALL INTO THE MID TO LOWER 30S  
(OUTSIDE OF DETROIT/IMMEDIATE LAKESHORE AREAS) OFFERING THE SEASON'S  
FIRST FROST CHANCES. SURFACE RIDGE AXIS SHIFTS TO THE EASTERN GREAT  
LAKES BY THURSDAY RE-ESTABLSIHING SOUTHWEST LOWER LEVEL FLOW AND  
GRADUAL WAA THROUGH THE REST OF THE WEEK. THAT SAID, SOME AREAS OF  
FROST ARE POSSIBLE AGAIN OVERNIGHT THURSDAY, PARTICULARLY IN THE  
THUMB, DUE TO ANOTHER CLEAR, CALM NIGHT UNDER DEPARTING THERMAL  
TROUGHING.  
 

 
   
MARINE
 
 
POST FRONTAL COLD AIR ADVECTION BRINGS AN UPTICK IN NORTHWEST WINDS  
ACROSS THE AREA THROUGH THE AFTERNOON INTO TONIGHT. GUSTS GENERALLY  
PEAK AROUND 25 KT OVER LAKE HURON, THOUGH SOME GUSTS TO 30 KT WILL  
BE POSSIBLE ACROSS THE NORTHERN PART OF THE LAKE THIS EVENING. A  
SMALL CRAFT ADVISORY REMAINS IN EFFECT FOR THE LAKE HURON NEARSHORE  
WATERS STARTING TONIGHT AS WAVES BUILD ACROSS THE SOUTHERN BASIN.  
WIND DIRECTION VEERS TO NORTH-NORTHEAST ON WEDNESDAY AS A SECONDARY  
COLD FRONT MOVES THROUGH, MAINTAINING WIND SPEEDS IN THE 10 TO 20 KT  
RANGE AND PRODUCING ONSHORE WAVE ACTIVITY THROUGH THE DAY. HIGH  
PRESSURE BUILDS DIRECTLY INTO THE AREA WEDNESDAY NIGHT AND OFFERS  
LIGHTER WINDS AND WAVES THROUGH THURSDAY. MODEST SOUTHWEST WIND THEN  
EMERGES ON FRIDAY AHEAD OF THE NEXT COLD FRONT ARRIVING INTO THE  
WESTERN GREAT LAKES.  
 

 
   
PREV DISCUSSION
 
 
ISSUED AT 146 PM EDT TUE OCT 7 2025  
 
AVIATION...  
 
THE COLD FRONT HAS PUSHED THROUGH THE REGION CURRENTLY OVER TTF AT  
PRESS TIME ON IT'S WAY OUT OF THE STATE. THERE IS STILL A BAND OF  
LIGHT SHOWERS AND VARYING CLOUD HEIGHTS THAT WILL PERSIST A FEW MORE  
HOURS WITH CIGS RANGING FROM IFR TO VFR. WILL HANDLE WITH A TEMPO  
BEFORE DRIER AIR FILLS IN FOR TONIGHT AND MAY CLEAR OUT THE SKIES.  
THERE IS ONE ADDITIONAL BAND OF CLOUDS ACROSS THE UP AND WI WHICH  
WILL SLIDE DOWN AND MAY SURVIVE THE DRIER AIR SO WILL KEEP A MENTION  
OF SCT CLOUDS AROUND 7KFT FOR A BIT TONIGHT BEFORE THE CLEAR SKIES  
SPREAD ACROSS LOWER MI. WINDS HAVE BECOME NORTHERLY AND WILL REMAIN  
THERE THROUGH THE FORECAST.  
 
FOR DTW/D21 CONVECTION... THUNDERSTORMS WILL NOT OCCUR THROUGH THE  
FORECAST PERIOD.  
 
DTW THRESHOLD PROBABILITIES...  
 
* HIGH FOR CEILING 5000 FT OR LESS THROUGH MID-DAY, DECREASING  
THROUGH THE AFTERNOON TO LOW BY 00Z.  
 

 
   
DTX WATCHES/WARNINGS/ADVISORIES
 
 
MI...NONE.  
LAKE HURON...SMALL CRAFT ADVISORY FROM 10 PM THIS EVENING TO 10 PM EDT WEDNESDAY  
FOR LHZ421-441>443.  
 
SMALL CRAFT ADVISORY FROM 10 PM THIS EVENING TO 10 AM EDT WEDNESDAY  
FOR LHZ422.  
 
LAKE ST CLAIR...NONE.  
MICHIGAN WATERS OF LAKE ERIE...NONE.  

 
 

 
 
DISCUSSION...KDK  
MARINE.......TF  
AVIATION.....DRK  
 
YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE  
AT WWW.WEATHER.GOV/DETROIT.  
 
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