293  
FXUS63 KDTX 220753  
AFDDTX  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI  
353 AM EDT MON JUN 22 2026  
   
KEY MESSAGES  
 
- SHOWERS WITH A RUMBLE OF THUNDER CONTINUE INTO EARLY MORNING,  
MAINLY SOUTH OF THE TRI CITIES AND NORTHERN THUMB, TRANSITIONING TO  
LIGHT RAIN BEFORE ENDING TOWARD NOON.  
 
- DRY WEATHER MOVES IN THIS AFTERNOON AND CONTINUES TONIGHT AND  
TUESDAY.  
 
- SLIGHTLY COOLER THAN NORMAL TEMPERATURES CONTINUE THROUGH MID TO  
LATE WEEK.  
 
- THE NEXT CHANCE OF RAIN ARRIVES WEDNESDAY AND WEDNESDAY NIGHT.  
 
 
   
DISCUSSION  
 
CLUSTERS/BANDS OF SHOWERS ARE IN PROGRESS OVER SOUTHERN LOWER MI  
PRIMARILY ASSOCIATED WITH THE STRONG MID LEVEL CIRCULATION THAT IS  
THE PARENT TO OHIO VALLEY SURFACE LOW PRESSURE. THE SYSTEM IS STILL  
SUPPORTING A WIDE RANGE OF CONVECTION FROM SEVERE THUNDERSTORMS  
ALONG AND AHEAD OF THE SURFACE FRONTS, TO ELEVATED BUT STILL  
CELLULAR SHOWERS NORTH OF THE SURFACE LOW, TO THE CLUSTERS/BANDS  
ACROSS MUCH OF SOUTHERN LOWER MI. LIGHTNING HAS BEEN ABSENT NORTH OF  
THE IN/OH BORDER SINCE MIDNIGHT, HOWEVER RAINFALL RATES HAVE STILL  
BEEN QUITE PRODUCTIVE AS THE LEADING STRATIFORM COMPONENT LAST  
EVENING QUICKLY TRANSITIONED TO CLUSTERS/BANDS AS 700 MB ISENTROPIC  
LIFT AND FRONTOGENESIS ACTIVATED AHEAD OF THE 500 MB CIRCULATION.  
THE MOST INTENSE CONCENTRATION OF CLUSTERS AND BANDING PRODUCED  
EVENT RAINFALL TOTALS IN THE 0.75 TO 1.25 INCH RANGE FROM NORTHERN  
IN INTO SW LOWER MI BASED ON SURFACE OBSERVATIONS AND RADAR  
ESTIMATES SINCE 00Z LAST EVENING UP TO PRESS TIME.  
 
THERE IS STILL AN ADDITIONAL ROUND OF SHOWERS AND A RUMBLE OF  
THUNDER YET TO GO AS RADAR COVERAGE STEADILY FILLS IN OVER CENTRAL  
IN/OH. THIS IS WHERE THE LOW LEVEL JET ACTIVATES NEW CONVECTION  
WITHIN THE 850-700 MB THETA-E GRADIENT BEFORE VEERING EASTWARD WITH  
THE SURFACE LOW CENTER. HREF AND REFS 3 HR PMM QPF CAPTURE THIS  
REASONABLY WELL AND SHOW IT GRAZING THE SE MI AREA SOUTH OF I-94  
FROM NOW THROUGH SUNRISE. AFTER THAT, PRECIPITATION RATE DIMINISHES  
WHILE COVERAGE IS MAINTAINED BY MID/UPPER LEVEL DEFORMATION FROM  
ABOUT THE MID THUMB SHORELINE TO LANSING DURING EARLY MORNING. THERE  
IS GOOD AGREEMENT IN THE 00Z MODELS THAT ALL RAIN ENDS IN SE MI  
AROUND NOON.  
 
SATELLITE IMAGERY UPSTREAM ACROSS THE NORTHERN GREAT LAKES THEN  
SUPPORTS A DECREASING CLOUD TREND OVER SE MI THIS AFTERNOON,  
ALTHOUGH IT MAY TAKE UNTIL LATE AFTERNOON TO CLEAR DETROIT.  
DECREASING CLOUDS IS MAINLY ASSOCIATED WITH LARGER SCALE SUBSIDENCE  
TRAILING THE MORNING LOW PRESSURE SYSTEM AS LOW LEVEL NORTHERLY FLOW  
IS JUST SLIGHTLY COOLER AND LESS HUMID. THE INBOUND HIGH PRESSURE  
AIR MASS GAINS GREATER PRESENCE LATE TONIGHT AND TUESDAY AS THE  
MID/UPPER LEVEL SHORT WAVE RIDGE BUILDS OVER THE MIDWEST WHILE  
KEEPING THE SURFACE RIDGE TO OUR WEST. THIS MAINTAINS MODERATE  
NORTHERLY WIND IN THE LOW LEVELS THAT IS STILL MILD ENOUGH FOR A  
FAIR WEATHER CUMULUS FIELD IN THE AFTERNOON. GUIDANCE HIGHS IN THE  
MID TO UPPER 70S FURTHER SUPPORTS THIS AIR MASS JUST MAINTAINING THE  
ALREADY SLIGHTLY BELOW NORMAL TEMPERATURE PATTERN OF RECENT DAYS.  
 
HIGH PRESSURE HOLDS TUESDAY NIGHT, BUT JUST BARELY, AS THE LONG WAVE  
MID/UPPER AIR PATTERN REMAINS LESS AMPLIFIED AND PROGRESSIVE. THIS  
HAS THE CURRENT CANADIAN ROCKIES SYSTEM REACHING THE GREAT LAKES  
WITHOUT MUCH FANFARE WEDNESDAY AND WEDNESDAY NIGHT. MODEL CONSENSUS  
TRACKS THE SURFACE LOW THROUGH THE NORTHERN GREAT LAKES WHICH SETS  
UP A STANDARD WARM FRONT/COLD FRONT PROGRESSION ACROSS SE MI FOR OUR  
NEXT CHANCE OF SHOWERS AND THUNDERSTORMS. THIS IS ANOTHER SYSTEM  
THAT BRINGS LITTLE CHANGE OF AIR MASS AS GUIDANCE TEMPERATURES HOLD  
IN THE MID TO UPPER 70S POST FRONT ON THURSDAY. THIS COULD CHANGE AS  
EXTENDED RANGE MODELS INDICATE A LARGER PATTERN SHIFT OCCURING NEXT  
WEEKEND RESULTING IN A LARGE CLOSED LOW OVER THE ROCKIES AND A  
DOWNSTREAM RIDGE OVER THE MIDWEST. GUIDANCE HIGH TEMPERATURES IN THE  
MID 80S ARE OFFERED IN SE MI BY SUNDAY.  
 
 
   
MARINE  
 
A COMPACT LOW PRESSURE SYSTEM WILL TRAVEL EAST ACROSS THE OHIO  
VALLEY THROUGH THE MORNING. THIS WILL SUSTAIN EAST TO SOUTHEAST FLOW  
ACROSS LAKE ERIE, AND WIND GUST POTENTIAL AROUND 25 KNOTS ALONG WITH  
ELEVATED WAVE HEIGHTS. A SMALL CRAFT ADVISORY REMAINS IN PLACE. SOME  
ISOLATED WIND GUSTS 20 TO 25 KNOTS WILL BE POSSIBLE ACROSS LAKE ST.  
CLAIR THIS MORNING, WITH LOWER MAGNITUDE WIND SPEEDS ACROSS LAKE  
HURON AND THE SAGINAW BAY. WIDESPREAD RAIN CONTINUES ACROSS THE  
SOUTHERN GREAT LAKES, TAPERING OFF IN THE LATE MORNING TO EARLY  
AFTERNOON. WIND DIRECTION BACKS NORTH TO NORTHWEST IN THE WAKE OF  
THE LOW THROUGH THE EARLY WEEK PERIOD AS HIGH PRESSURE BUILDS IN.  
LIGHTER WINDS ARE EXPECTED TOMORROW AND WEDNESDAY.  
 
 
   
HYDROLOGY  
 
WIDESPREAD SHOWERS ARE IN PROGRESS OVER SE MI GENERALLY SOUTH OF THE  
TRI CITIES AND NORTHERN THUMB. THERE IS A CHANCE OF LOCALLY HEAVY  
RAINFALL IN THIS PATTERN THROUGH EARLY MORNING, ESPECIALLY TOWARD  
THE OHIO BORDER. EVENT TOTAL AMOUNTS OF 0.5 TO 1.0 INCH ARE LIKELY  
ALONG AND SOUTH OF I-69, WITH A CHANCE OF LOCALIZED TOTALS AROUND  
1.5 INCHES MAINLY SOUTH OF DETROIT TO THE OHIO BORDER BEFORE  
INTENSITY DIMINISHES CONSIDERABLY AROUND SUNRISE. THESE RAINFALL  
TOTALS AND TIME RANGES SUGGEST THE POTENTIAL FOR FLOODING WILL BE  
LIMITED TO PONDING OF WATER ON ROADWAYS AND OTHER PRONE AREAS.  
 
 
   
PREV DISCUSSION  
 
ISSUED AT 1156 PM EDT SUN JUN 21 2026  
 
AVIATION...  
 
DEEPER PLUME OF MOISTURE EVIDENT NORTH OF A LOW PRESSURE SYSTEM  
TRACKING ACROSS THE OHIO VALLEY WILL EXPAND ACROSS SOUTHEAST  
MICHIGAN THRU THE EARLY-MID MORNING HOURS. THIS WILL TRANSLATE INTO  
WIDESPREAD RAINFALL, WITH AN ACCOMPANYING DECLINE IN CEILING HEIGHT  
WITH TIME. UPSTREAM OBSERVATIONAL TRENDS PAIRED WITH RECENT MODEL  
GUIDANCE CONTINUE TO SUPPORT AN EVENTUAL DECLINE IN IFR AT PTK AND  
THE DETROIT CORRIDOR LATE TONIGHT. MVFR CONDITIONS MOST LIKELY AT  
FNT, WHILE MBS HOVERS AT THE FRINGE OF MVFR/LOW VFR FOR A BRIEF TIME  
NEAR DAYBREAK. SOME REDUCTION OF VISIBILITY INTO THE 2 TO 4 MILE  
RANGE WILL ALSO BE POSSIBLE. LITTLE EVIDENCE OF THUNDERSTORMS  
ACTIVITY THUS FAR, SUGGESTING ELEVATED INSTABILITY LACKS TO SUPPORT  
A GREATER POSSIBILITY AND WILL REFRAIN FROM ANY MENTION. PREVAILING  
WINDS EMERGING FROM THE EAST/NORTHEAST OVERNIGHT, THEN TURNING  
MODESTLY GUSTY ON MONDAY. GRADUAL IMPROVEMENT IN CONDITIONS AS RAIN  
TAPERS OFF BY LATE MORNING AND DAYTIME MIXING ENSUES. THIS WILL  
BRING A PROGRESSIVE TRANSITION FROM MVFR BACK INTO VFR WITH A  
LINGERING COVERAGE OF HIGH BASED CU FOR THE AFTERNOON.  
 
D21/DTW CONVECTION... THUNDERSTORMS POTENTIAL REMAINS VERY LOW FOR  
LATE TONIGHT.  
 
DTW THRESHOLD PROBABILITIES...  
 
* HIGH FOR CEILING AT OR BELOW 5000 FT TONIGHT AND MOST OF MONDAY.  
 
* VERY LOW FOR THUNDERSTORMS LATE TONIGHT.  
 
 
   
DTX WATCHES/WARNINGS/ADVISORIES  
 
MI...NONE.  
LAKE HURON...NONE.  
LAKE ST CLAIR...NONE.  
MICHIGAN WATERS OF LAKE ERIE...SMALL CRAFT ADVISORY UNTIL 5 PM EDT THIS AFTERNOON FOR LEZ444.  
 
 
 
 
 
DISCUSSION...BT  
MARINE.......AM  
HYDROLOGY....BT  
AVIATION.....MR  
 
YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE  
AT WWW.WEATHER.GOV/DETROIT.  
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