733  
FXUS63 KDTX 291639  
AFDDTX  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI  
1239 PM EDT SAT AUG 29 2026  
   
KEY MESSAGES
 
 
- SEASONABLE TEMPERATURES WITH DRY WEATHER THROUGH MOST OF THE DAY  
TODAY.  
 
- INCREASING CHANCES FOR SHOWERS AND STORMS TONIGHT THROUGH  
TOMORROW. SHOWER AND STORM CHANCES CONTINUE THROUGH THE EARLY WEEK.  
 
- HUMIDITY BUILDS FOR THE EARLY TO MID WEEK PERIOD.  
 

 
   
AVIATION
 
 
VFR CONDITIONS HOLD THROUGH THE REMAINDER OF THE DAYLIGHT PERIOD, AS  
HIGH BASED CLOUD THICKENS WITH TIME DOWNSTREAM OF AN AREA OF  
CONVECTION NOW LIFTING ACROSS WISCONSIN. THIS MOISTURE WILL LIFT  
INTO LOWER MICHIGAN THIS EVENING WHILE GRADUALLY DIMINISHING IN  
COVERAGE AND INTENSITY. EXPECTATION REMAINS FOR SIMPLY A LIMITED  
PROBABILITY FOR A FEW SHOWERS TO SURVIVE, MAINLY AT MBS, WITH LITTLE  
CONSEQUENCE. ADDITIONAL LIGHT SHOWER DEVELOPMENT WILL REMAIN  
POSSIBLE OVERNIGHT, THEN WITH HIGHER PROBABILITY SUNDAY MORNING  
AGAIN WITH HIGHER PROBABILITY AT MBS/FNT. WARM FRONT SETS UP OVER  
THE REGION SUNDAY, WHICH MAY INTRODUCE THE POTENTIAL FOR A FEW  
THUNDERSTORMS DURING THE LATTER HALF OF THE DAY AS INSTABILITY  
INCREASES WITH DAYTIME HEATING.  
 
D21/DTW CONVECTION...NO CONVECTION IS FORECAST THROUGH TONIGHT.  
   
DTW THRESHOLD PROBABILITIES
 
 
* NONE.  
 

 
   
PREV DISCUSSION
 
 
ISSUED AT 326 AM EDT SAT AUG 29 2026  
 
DISCUSSION...  
 
RAPID THUNDERSTORM DEVELOPMENT IS ONGOING ACROSS THE NORTHERN PLAINS  
EARLY THIS MORNING ALONG THE NOSE OF A STRENGTHENING SOUTHERLY LLJ.  
THIS ACTIVITY IS EXPECTED TO ORGANIZE INTO AN MCS AND PROGRESS  
THROUGH THE UPPER MIDWEST TODAY BEFORE TRAVERSING INTO THE GREAT  
LAKES TONIGHT INTO EARLY TOMORROW. GIVEN LITTLE TO NO INSTABILITY  
ACROSS THE GREAT LAKES, A WEAKENING TREND OF THIS COMPLEX REMAINS  
FAVORED, ALTHOUGH LATEST HI-RES GUIDANCE BRINGS SOME INCREASING  
CONFIDENCE THAT PORTIONS OF THE MCS CAN REACH SOUTHEAST MICHIGAN.  
 
THIS SOUTHERLY LOW-LEVEL FLOW ACROSS THE PLAINS WILL FOLD FROM IOWA  
INTO WISCONSIN THROUGH THE MORNING HOURS AND WHILE THE  
AFOREMENTIONED MCS IS EXPECTED TO OUTPACE THE NASCENT MOISTURE  
SOURCE, THE NOCTURNAL REINFORCEMENT OF THE LLJ COULD SUPPORT  
REDEVELOPMENT OR REINVIGORATION OF SHOWERS AND EMBEDDED  
THUNDERSTORMS ALONG THE BACKSIDE OF THE MCS DESPITE LIMITED  
INSTABILITY. THIS CAN SUPPORT RAIN AND THUNDERSTORM CHANCES INTO THE  
EARLY AFTERNOON ACROSS SE MI. ADDITIONALLY THIS CORRIDOR OF ENHANCED  
THETA-A WILL STRENGTHEN ISENTROPIC ASCENT ALONG OR NORTH OF THE I-69  
CORRIDOR, PROVIDING CONTINUED SUPPORT FOR SHOWERS AND THUNDERSTORMS  
INTO THE LATTER HALF OF THE DAY. DEVELOPMENT ALONG THIS CONVERGENT  
BOUNDARY IN THE AFTERNOON/EVENING WOULD LIKELY BE A LITTLE MORE  
LOCALIZED. OVERALL THERE REMAINS UNCERTAINTY REGARDING HOW THESE  
INDIVIDUAL POTENTIAL ROUNDS OF PRECIPITATION WILL EVOLVE AND  
OVERLAP, BUT CONFIDENCE HAS INCREASED IN A CONSIDERABLY MORE  
UNSETTLED SUNDAY.  
 
GIVEN THE ABOVE, CONFIDENCE IS INCREASING THAT NBM TEMPERATURES ARE  
LIKELY OVERDONE ON SUNDAY. AN ACTIVE CONVECTIVE PATTERN AND  
PERSISTENT CLOUD COVER WILL LIMIT MEANINGFUL INSOLATION. IF THE MORE  
ACTIVE SETUP PLAYS OUT AS PROJECTED, HIGHS WILL BE CAPPED IN THE  
70S, WITH LOW 80S POSSIBLE ONLY WHERE COVERAGE IS REDUCED FOR A  
LONGER PERIOD OF TIME.  
 
A VERY MOIST AND ACTIVE PATTERN WILL PERSIST IN THE EARLY AND  
MIDWEEK PERIOD. ENSEMBLE GUIDANCE HIGHLIGHTS STRONG WEST TO EAST  
INTEGRATED WATER VAPOR TRANSPORT ACROSS THE REGION INTO WEDNESDAY.  
PW VALUES OF 1.75 TO 2.00" AND WARM-CLOUD DEPTHS APPROACHING 13KFT  
WILL SUPPORT EFFICIENT RAINFALL PRODUCTION. MID-LEVEL DISTURBANCES  
WITHIN QUASI-ZONAL FLOW UNDER THIS SETUP WILL BRING MULTIPLE  
OPPORTUNITIES FOR SHOWERS AND THUNDERSTORMS. REPEATED CONVECTION  
ALONG THE SAME AREAS WILL BRING A LOCALIZED FLOODING RISK. IN THE  
SAME REGARD FOR SUNDAY TEMPERATURES, EARLY WEEK HIGHS WILL BE  
CONDITIONAL ON CLOUD COVERAGE AND SHOWER CHANCES. TEMPERATURES WILL  
LIKELY NEED TO BE TEMPERED DOWN IF NEW GUIDANCE HIGHLIGHTS SE MI AS  
A SUSCEPTIBLE CORRIDOR FOR REPEATED PRECIPITATION.  
 
MARINE...  
 
INFLUENCE OF HIGH PRESSURE WANES THIS MORNING AS IT SHIFTS TO THE  
NORTHEAST WITH THE CENTRAL GREAT LAKES HOLDING ON ITS WESTERNMOST  
FRINGE. THIS ALLOWS FOR MODEST SOUTHWEST WINDS TO DEVELOP DURING THE  
DAY WITH GUSTS HOLDING AOB 20KTS, SAVE FOR CENTRAL LAKE HURON WHERE  
FAVORABLE FETCH COULD ALLOW FOR UP TO 25KTS. ACTIVE PATTERN RETURNS  
BY SUNDAY AS DEVELOPING LOW PRESSURE OVER THE NORTHERN PLAINS LIFTS  
A WARM FRONT THROUGH THE AREA USHERING IN A MORE HUMID AIRMASS  
LEADING NUMEROUS SHOWER/STORM CHANCES SUNDAY INTO MONDAY.  
 

 
   
DTX WATCHES/WARNINGS/ADVISORIES
 
 
MI...NONE.  
LAKE HURON...NONE.  
LAKE ST CLAIR...NONE.  
MICHIGAN WATERS OF LAKE ERIE...NONE.  

 
 

 
 
AVIATION.....MR  
DISCUSSION...AM  
MARINE.......KDK  
 
YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE  
AT WWW.WEATHER.GOV/DETROIT.  
 
CLICK HERE TO GO TO PREVIOUS BULLETINS.

The Nexlab MI Page Main Text Page