513  
FXUS63 KDTX 221741  
AFDDTX  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI  
1241 PM EST SAT NOV 22 2025  
   
KEY MESSAGES  
 
- MAINLY DRY CONDITIONS THIS WEEKEND ASIDE FROM A SLIGHT CHANCE FOR  
A SHOWER IN THE THUMB REGION LATE TONIGHT  
 
- BREEZY CONDITIONS DEVELOP SUNDAY WITH NORTHWEST WINDS GUSTING  
25 TO 35 MPH  
 
- CHANCE FOR BROADER RAINFALL INCREASES DURING THE FIRST HALF OF  
NEXT WEEK.  
 
- COLDER AIR AND LAKE EFFECT SNOW SHOWERS ARE POSSIBLE THROUGH THE  
LATTER HALF OF NEXT WEEK.  
 
 
   
AVIATION  
 
WIND DIRECTION WILL BECOME WESTERLY THIS AFTERNOON AND CONTINUE TO  
BACK TOWARDS THE SOUTH THIS EVENING IN RESPONSE TO THE DEPARTING  
HIGH AND INCREASING INFLUENCE OF THE ONTARIO LOW PRESSURE. WIND  
SPEEDS DURING THIS TIME SHOULD STILL HOLD BELOW 10 KNOTS THROUGH THE  
EVENING WHILE COVERAGE OF MID AND HIGH CLOUDS INCREASES. THE ARRIVAL  
OF A WARM FRONT WILL QUICKLY BE FOLLOWED BY A COLD FRONT AND LEAD TO  
A PERIOD OF MVFR CEILINGS SPREADING ACROSS THE TERMINALS FROM NW TO  
SOUTHEAST TOWARD EARLY TOMORROW MORNING. POST FRONTAL WINDS WILL  
VEER WINDS BACK TOWARDS THE W-WNW EARLY TOMORROW MORNING WITH GUSTS  
EXPECTED TO INCREASE TO 20 KNOTS OR GREATER WITHIN A COUPLE HOURS  
AFTER SUNRISE AND CONTINUE INTO THE AFTERNOON. CEILINGS IMPROVEMENTS  
EXPECTED BY LATE TOMORROW MORNING AND AFTERNOON AS CLOUDS START TO  
SCATTER OUT.  
 
DTW THRESHOLD PROBABILITIES...  
 
* MODERATE FOR CEILING 5000 FT OR LESS LATE TONIGHT AND TOMORROW  
MORNING.  
 
 
   
PREV DISCUSSION  
 
ISSUED AT 358 AM EST SAT NOV 22 2025  
 
DISCUSSION...  
 
MAJORITY OF OBSERVING SITES ARE REPORTING CLEAR SKIES THIS MORNING,  
WHICH IS IN LINE WITH NIGHTTIME SATELLITE IMAGERY THAT SHOWS THE  
CLOUD SHIELD CONTRACTING TOWARD THE OHIO VALLEY/EAST COAST. THAT  
SAID, THE IMPACTS OF THIS CLOUD DECK LINGER TOWARD DAYBREAK AS  
TEMPERATURES IN THE SAGINAW VALLEY/THUMB ARE RUNNING ROUGHLY 10-15  
DEGREES COOLER THAN SOUTHERN LOCATIONS WHERE RADIATIVE COOLING IS  
JUST NOW RAMPING UP. SUB-ZERO 850MB TEMPERATURES EXIST ACROSS MOST  
OF THE CWA, WHICH COMBINED WITH THICKENING MID/HIGH CLOUD BY THIS  
AFTERNOON KEEPS DAYTIME HIGHS CAPPED IN THE LOW-MID 40S.  
 
QUICK TRANSITION BACK TO AN ACTIVE PATTERN OCCURS THIS EVENING AS A  
CLIPPER RACES ACROSS ONTARIO, DRAWING A COLD FRONT ACROSS THE GREAT  
LAKES OVERNIGHT. MODELS HAVE TRENDED TOWARD A STRONGER, CLOSED  
SURFACE LOW WITH A MORE PRONOUNCED SURFACE TROUGH EXTENDING INTO  
LOWER MICHIGAN. STILL, THIS SYSTEM STRUGGLES WITH MOISTURE AS COLUMN  
SATURATION REMAINS DISJOINTED WITH THE ONSLAUGHT OF A MID-LEVEL DRY  
SLOT AND NARROW LOW LEVEL MOISTURE CONVERGENCE ALONG THE FRONT.  
MODEL PRECIPITATION FIELDS CONTINUE TO GENERATE MOST OF THE QPF  
CLOSE TO THE SURFACE LOW/OVER THE LAKES, ALTHOUGH THE STRONGER LOW  
HAS SPREAD THE FORECAST PRECIPITATION SHIELD A BIT FURTHER SOUTH.  
DID ADD IN SLIGHT CHANCE POPS ACROSS THE THUMB AS A RESULT OF THESE  
TRENDS, BUT STILL THINK THE DEPTH OF THE DRY AIR WILL BE TOUGH TO  
OVERCOME TO KEEP MOST OF SE MICHIGAN DRY OVERNIGHT.  
 
STRONG ISENTROPIC DOWNGLIDE BEGINS IMMEDIATELY BEHIND THE FRONT,  
WITH THE INITIAL SUBSIDENT LAYER TRAPPING LOW CLOUD SUNDAY MORNING.  
SHOULD SEE THIS BEGIN TO MIX OUT BY MID-DAY, ESPECIALLY AS THE  
INBOUND SURFACE HIGH PROVIDES A STEADY FEED OF DRIER CANADIAN AIR  
OVERHEAD. INCREASING MIXING DEPTHS QUICKLY INTERSECT WITH THE 35-40  
KNOT LOW LEVEL WIND FIELD, RESULTING IN BREEZY CONDITIONS SUNDAY  
AFTERNOON. GUSTS UP TO 35 MPH WILL BE POSSIBLE, WITH HIGHEST GUSTS  
ACROSS THE THUMB REGION (CLOSER PROXIMITY TO THE LOW). ALSO OF NOTE  
ON SUNDAY IS THE ONSET OF WARM ADVECTION INTO THE GREAT LAKES, IN  
WHICH H8 TEMPERATURES GRADUALLY CLIMB INTO THE POSITIVE SINGLE  
DIGITS BY MONDAY. HIGH TEMPERATURES BOTH MONDAY AND TUESDAY ARE  
FORECAST TO BE IN THE 50S, WELL ABOVE NORMAL FOR LATE NOVEMBER.  
 
DRY CONDITIONS PERSIST THROUGH EARLY TUESDAY, AHEAD OF THE NEXT PAIR  
OF WEATHER SYSTEMS AND A MARKED SHIFT TOWARD COOLER CONDITIONS BY  
THE END OF THE HOLIDAY WEEK. MODELS CONTINUE TO SHOW TWO WAVES  
EJECTING OUT OF THE PACIFIC THIS WEEKEND, REMAINING WELL OUT OF  
PHASE WITH THE SOUTHERN STREAM WAVE BEING THE FIRST TO IMPACT SE  
MICHIGAN TUESDAY. MAIN IMPACT FROM THIS WILL BE WIDESPREAD  
PRECIPITATION, WITH A WEAKENING TREND TO THE SYSTEM EXPECTED AS IT  
TRACKS THROUGH. ABOVE NORMAL WARMTH ENSURES P-TYPE IS ALL RAIN. THE  
TRAILING NORTHERN STREAM WAVE SHOWS MORE IMPACT POTENTIAL,  
ESPECIALLY AS IT INTERACTS WITH THE EXISTING SURFACE LOW UPSTREAM.  
THIS SYSTEM DRAWS A STRONG COLD FRONT ACROSS THE GREAT LAKES  
WEDNESDAY, KICKSTARTING THE ADVERTISED COLD TEMPERATURES FOR THE  
HOLIDAY WEEKEND. THE COLDER AIR FLOWING OVER THE STILL WARM LAKES IS  
A STANDARD SETUP FOR LAKE EFFECT POTENTIAL, ALTHOUGH IT IS TOO FAR  
OUT FOR ADDITIONAL DETAILS TO BE DISCERNED.  
 
MARINE...  
 
HIGH PRESSURE IN PLACE TODAY WILL SUPPORT LIGHT NORTHWEST TO WEST  
WINDS UNDER 15 KNOTS. LOW PRESSURE TRACKING THROUGH ONTARIO TONIGHT  
WILL SEND ANOTHER COLD FRONT THROUGH THE CENTRAL GREAT LAKES.  
GUIDANCE HAS TRENDED TOWARD A DEEPER LOW WITH A MORE SOUTHERLY  
TRACK, GENERATING GUSTY WINDS BEHIND THE FRONT AS 850 MB TEMPS ARE  
PROGGED TO BOTTOM OUT AROUND -6 C. NORTHERN LAKE HURON WILL SEE THE  
STRONGEST GUSTS TO AROUND 35 KNOTS, PROMPTING THE ISSUANCE OF A GALE  
WARNING. ELSEWHERE, WINDS LOOK TO GUST IN THE 20-30 KNOT RANGE  
BEHIND THE FRONT ON SUNDAY, WITH SMALL CRAFT ADVISORIES ISSUED FOR  
ALL OF THE LAKE HURON NEARSHORE AS A RESULT. RIDGE OF HIGH PRESSURE  
QUICKLY BUILDS IN SUNDAY EVENING, ALLOWING FOR WINDS TO SUBSIDE  
SUNDAY NIGHT BELOW HEADLINE THRESHOLDS. LIGHT TO MODERATE SOUTHERLY  
RETURN FLOW THEN DEVELOPS EARLY NEXT WEEK.  
 
 
   
DTX WATCHES/WARNINGS/ADVISORIES  
 
MI...NONE.  
LAKE HURON...GALE WARNING FROM 7 AM TO 4 PM EST SUNDAY FOR LHZ361-362.  
 
SMALL CRAFT ADVISORY FROM 1 AM TO 4 PM EST SUNDAY FOR LHZ421-441.  
 
SMALL CRAFT ADVISORY FROM 7 AM TO 4 PM EST SUNDAY FOR LHZ422-442-  
443.  
 
LAKE ST CLAIR...NONE.  
MICHIGAN WATERS OF LAKE ERIE...NONE.  
 
 
 
 
AVIATION.....AA  
DISCUSSION...MV  
MARINE.......MV/SF  
 
YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE  
AT WWW.WEATHER.GOV/DETROIT.  
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