636  
FXUS63 KDTX 050701  
AFDDTX  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI  
301 AM EDT FRI SEP 5 2025  
   
KEY MESSAGES
 
 
- BECOMING WINDY TODAY WITH SOUTHWEST-WEST WIND GUSTS UP AROUND 40  
MPH.  
 
- COLD THIS WEEKEND WITH HIGHS IN THE 60S AND LOWS IN THE 40S.  
 
- ISOLATED SHOWERS POSSIBLE OVER THE WEEKEND, ESPECIALLY NORTH OF M-  
46.  
 

 
   
DISCUSSION
 
 
LARGE UPPER LEVEL LOW/TROUGH CENTERED OVER NORTHERN ONTARIO WILL  
DIRECT A SERIES OF SHORTWAVES/COLD SHOTS INTO THE GREAT LAKES REGION  
THROUGH THE WEEKEND. 00Z RAOB OUT OF INTERNATIONAL FALLS MINNESOTA  
REVEALED AN 850 MB TEMP OF 0 C, WITH THIS COLD AIR ARRIVING TONIGHT  
INTO SATURDAY, MODIFIED BY THE MILD WATERS OF THE GREAT LAKES  
REGION.  
 
TODAY'S MAX TEMP FORECAST IS A BIT TRICKY AS THE STRONG COLD FRONT  
CROSSES SOUTHEAST MICHIGAN AROUND NOON, WITH GOOD LOW LEVEL COLD  
ADVECTION BEHIND THE FRONT. 925 MB TEMPS OF 15+ C ALONG AN ADRIAN-  
PONTIAC-PORT HURON LINE (BLEND OF REGIONAL GEM/NAM/RAP/HRRR)  
SUPPORTS HIGHS IN THE LOWER 70S EAST, WITH UPPER 60S WEST.  
 
MIXING DEPTHS INCREASING TO 850 MB LEVEL ALONG/BEHIND THE FRONT WILL  
SUPPORT WINDY CONDITIONS, WITH GUSTS OF 35-40 MPH. ISOLATED GUSTS TO  
45 MPH ARE POSSIBLE WITH IN ANY CONVECTIVE ROLLS AS THE 50 KNOT LOW  
LEVEL JET SLOWLY WANES/EXISTS EAST.  
 
850 MB TEMPS IN THE LOWER SINGLE NUMBERS THROUGH THE WEEKEND AND  
SBCAPES OF 50-100 J/KG INTERSECTING THE FREEZING LEVEL WILL BRING A  
CHANCE OF LAKE ENHANCED ACTIVITY, PARTICULARLY ACROSS THE NORTHERN  
THIRD OF THE CWA WITH A LAKE SUPERIOR-MICHIGAN CONNECTION SETTING UP  
AS LOW LEVEL WINDS TREND TO THE NORTHWEST BY THE SECOND HALF OF THE  
WEEKEND. MIN TEMPS WILL BE DEPENDENT ON THE AMOUNT OF CLOUDS AROUND,  
BUT 40S ARE EXPECTED EITHER WAY. LOWER 40S WOULD BE NO PROBLEM IF  
SKIES REMAIN MOSTLY CLEAR TO PARTLY CLOUDY, BUT CONFIDENCE IS LOW,  
AS THERE ARE SIGNS OF TROUGHING AND ISOLATED SHOWERS AROUND FOR  
SATURDAY NIGHT AS THE MID LEVEL COLD POOL OF -7 OF -8 C AT 700 MB  
MOVES OVERHEAD. POTENTIAL TO DIP AOB 40 DEGREES SUNDAY NIGHT AS  
WINDS DIE OFF AND SURFACE DEW PTS SLIP INTO UPPER 30S TO AROUND 40  
DEGREES.  
 
BUILDING HEIGHTS AND A STRONG WARM ADVECTION PATTERN DEVELOPS EARLY  
NEXT WEEK, AS 850 MB TEMPS PUSH INTO THE LOWER TEENS LATE TUESDAY  
AHEAD OF YET ANOTHER COLD FRONT, WHICH LOOKS TO SLOWLY TRACK THROUGH  
ON WEDNESDAY. BULK OF EURO ENSEMBLE MEMBERS PUSHING TEMPS INTO THE  
UPPER 70S FOR MUCH OF SOUTHEAST MICHIGAN ON WEDNESDAY, WITH A DRY OR  
MOSTLY DRY FRONTAL PASSAGE DUE TO THE LIMITED UPPER LEVEL SUPPORT  
AND MOISTURE.  
 

 
   
MARINE
 
 
WIND EVENT ACROSS THE GREAT LAKES COMMENCES THIS MORNING AS THE  
SURFACE LOW GOVERNING THE WIND IS BEGINNING TO PASS OVER THE EASTERN  
U.P. AT PRESS TIME. WINDS ORGANIZE OUT OF THE SOUTH THROUGH THE  
EARLY MORNING AS THE MATURE LOW BRINGS A TIGHT PRESSURE GRADIENT  
ACROSS LAKE HURON AND POINTS SOUTHWARD. SUSTAINED WINDS AROUND 30KTS  
ARE EXPECTED ACROSS THE BULK OF LAKE HURON BY MID MORNING AS GUSTS  
INCREASE TOWARDS 35KTS. LOW SLIDES NORTHEAST TOWARDS NORTHERN  
ONTARIO THROUGH THE DAY WHILE DRAGGING A COLD FRONT ACROSS THE  
REGION RESULTING IN WINDS SHIFTING TOWARDS THE WEST-SOUTHWEST BY  
LATE MORNING. AS THIS OCCURS, A 40-50KT LOW LEVEL JET IS SET TO  
EXPAND OVER THE CENTRAL GREAT LAKES SUPPORTING A FURTHER UPTICK IN  
WIND GUSTS TOWARDS 40KTS OVER LAKE HURON. A FEW GUSTS APPROACHING  
45KTS WITH SUSTAINED WINDS NEAR 34KTS NOT OUT OF THE QUESTION FOR  
CENTRAL LAKE HURON LATE MORNING-EARLY AFTERNOON (~10A-2P). ALL OF  
LAKE HURON IS UNDER A GALE WARNING THROUGH THIS EVENING AS A RESULT.  
LAKES ST CLAIR AND ERIE EXPECTED TO SEE WEAKER WINDS GIVEN THEIR  
DISPLACEMENT SOUTHWARD FROM THE LOW WITH GUSTS HOLDING MORE IN THE  
LOWER 30KT RANGE. SMALL CRAFT ADVISORIES ARE IN EFFECT FOR BOTH OF  
THESE BODIES OF WATERS BUT WILL BE WATCHING OBSERVATIONS FOR THE  
POTENTIAL UPGRADE TO GALE WARNING IF NEED BE. WITH THE CURRENT WIND  
FORECAST, WATER LEVELS IN BOTH THE SAGINAW BAY AND WESTERN LAKE ERIE  
NEAR OR FALL BELOW LOW WATER ADVISORY CRITERIA THIS MORNING. THESE  
TRENDS WILL BE MONITORED AND WITH ISSUANCE OF AN ADVISORY  
POTENTIALLY NEEDED IN COMING FORECAST UPDATES. WITH A COOLER AIRMASS  
EXPANDING BACK OVER THE LAKES, WATERSPOUTS WILL AGAIN BE POSSIBLE  
TODAY INTO THIS WEEKEND. COOLER, UNSETTLED WEATHER LINGERS INTO  
EARLY NEXT WEEK AS THE UPPER TROUGH SETTLES OVER THE GREAT LAKES.  
 

 
   
PREV DISCUSSION
 
 
ISSUED AT 1156 PM EDT THU SEP 4 2025  
 
AVIATION...  
 
STEADY INCREASE IN SOUTHERLY FLOW COMMENCES TONIGHT, DOWNSTREAM OF  
STRENGTHENING LOW PRESSURE LIFTING INTO THE NORTHERN GREAT LAKES.  
VFR CONDITIONS WITH LIMITED CLOUD COVERAGE THROUGH THE EARLY MORNING  
HOURS AS GREATER LOW LEVEL STABILITY HOLDS. THICKENING MID CLOUD FOR  
THE MID-LATE MORNING PERIOD, AS THE NOTED UPTICK IN WIND SPEED OFF  
THE SURFACE SUPPORTS A LOW LEVEL WIND SHEAR MENTION. BRIEF WINDOW  
FOR SHOWER DEVELOPMENT MAINLY AT MBS DURING THIS TIME. EMERGING  
GUSTINESS TO SOUTHWEST WIND FOR THE AFTERNOON HOURS, PEAKING AROUND  
30 KNOTS.  
 
FOR DTW/D21 CONVECTION... NO THUNDERSTORMS EXPECTED THROUGH THE  
PERIOD.  
 
THRESHOLD PROBABILITIES...  
 
* LOW FOR CIGS AT 5000 FEET OR LESS FRIDAY.  
 

 
   
DTX WATCHES/WARNINGS/ADVISORIES
 
 
MI...BEACH HAZARDS STATEMENT FROM 8 AM EDT THIS MORNING THROUGH THIS  
EVENING FOR MIZ049-055-063-083.  
 
LAKE HURON...GALE WARNING UNTIL 10 PM EDT THIS EVENING FOR LHZ361>363-421-422-  
441>443-462>464.  
 
LAKE ST CLAIR...SMALL CRAFT ADVISORY UNTIL 10 PM EDT THIS EVENING FOR LCZ460.  
 
MICHIGAN WATERS OF LAKE ERIE...SMALL CRAFT ADVISORY UNTIL 10 PM EDT THIS EVENING FOR LEZ444.  
 

 
 

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