588  
FXUS63 KMQT 231916  
AFDMQT  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE MARQUETTE MI  
316 PM EDT WED JUL 23 2025  
   
KEY MESSAGES
 
 
- SHOWERS AND THUNDERSTORMS ARE EXPECTED TONIGHT INTO THURSDAY.  
 
- THUNDERSTORMS COULD PRODUCE HEAVY RAIN, DAMAGING WINDS AND AN  
ISOLATED TORNADO.  
 
- THERE IS THE RISK FOR EXCESSIVE RAINFALL OVER MOST OF THE U.P. A  
FLOOD WATCH FOR POTENTIAL FLASH FLOODING IS IN EFFECT OVER THE  
WESTERN U.P WHERE SOILS ARE ALREADY SATURATED FROM HEAVY RAIN LAST  
NIGHT.  
 
- ADDITIONAL NON-SEVERE THUNDERSTORMS ARE POSSIBLE THURSDAY,  
ENDING WEST TO EAST.  
 
- STRONG WINDS AND LARGE WAVES WILL RESULT IN DANGEROUS SWIMMING  
CONDITIONS ON LAKE MICHIGAN BEACHES OF SCHOOLCRAFT COUNTY.  
 

 
   
SHORT TERM /THROUGH THURSDAY/
 
 
ISSUED AT 307 PM EDT WED JUL 23 2025  
 
THE UPPER LEVEL PATTERN THIS AFTERNOON SHOWS TROUGHING OVER MUCH OF  
CANADA WITH A SHORTWAVE TROUGH APPROACHING THE NORTHERN PLAINS. AN  
UPPER LEVEL HIGH PRESSURE WAS OVER THE SOUTHEASTERN U.S WITH THE  
RIDGE AXIS EXTENDING NORTH INTO THE EASTERN GREAT LAKES.  
MULTIPLE SMALLER SCALE SHORTWAVES WERE MOVING THROUGH THE UPPER  
MIDWEST AND APPROACHING UPPER GREAT LAKES. SHOWERS AND  
THUNDERSTORMS HAD DEVELOPED OVER CENTRAL AND NORTHERN MN AND  
NORTHWEST WI. SOME OF THESE WERE STARTING TO PUSH INTO THE FAR  
WEST AND SOUTH.  
 
SOUTHERLY FLOW WAS TRANSPORTING ABUNDANT MOISTURE INTO THE AREA  
WITH PRECIPITABLE WATER VALUES APPROACHING 2 INCHES. OBSERVED  
SOUNDINGS THIS MORNING AT MPX AND GRB BOTH SHOWED PW VALUES OF  
1.87 AND 1.84 RESPECTIVELY. THIS IS WELL ABOVE THE 90TH  
PERCENTILE OF CLIMATOLOGY FOR LATE JULY.  
 
THE AFOREMENTIONED SHORTWAVES WILL MOVE THOUGH THE AREA TONIGHT  
WHILE A COLD FRONT PUSHES SOUTHEAST THROUGH THE AREA. THIS WILL  
RESULT IN MULTIPLE ROUNDS OF SHOWERS AND THUNDERSTORMS. GUIDANCE  
FROM THE CAMS IS ALL OVER THE PLACE WITH TIMING AND LOCATION OF  
CONVECTION. ONE THING THAT THEY DO AGREE ON IS A CONVECTIVE  
MODE THAT IS MOSTLY LINEAR GIVEN THE STORM MOTION AND SHEAR  
RELATIVELY PARALLEL TO THE BOUNDARY. SHEAR WILL INCREASE THROUGH  
THE EVENING WHICH SHOULD BE ABLE TO SUPPORT MORE ORGANIZED  
CONVECTION. HEAVY RAINFALL AND DAMAGING WINDS WILL BE THE MAIN  
THREAT FROM THE STORMS. A DEEP WARM AIRMASS WILL LIMIT THE HAIL  
POTENTIAL. A STRENGTHENING LOW LEVEL JET WILL BRING INCREASING  
LOW LEVEL WIND SHEAR THIS EVENING. LOW LEVEL WIND SHEAR AND  
INSTABILITY LOOK SUFFICIENT FOR AN ISOLATED TORNADO THREAT,  
MAINLY WITH ANY BOWING SEGMENTS THAT FORM THIS EVENING.  
 
EXCESSIVE RAINFALL WILL CONTINUE TO BE A CONCERN WITH TORRENTIAL  
DOWNPOURS POSSIBLE WITH ANY STORMS, ESPECIALLY IN AREAS WHERE  
THUNDERSTORMS TRAIN ALONG THE FRONT. THERE IS A SLIGHT RISK FOR  
EXCESSIVE RAINFALL ACROSS THE ENTIRE U.P THIS EVENING AND  
OVERNIGHT. OVER THE WEST SOILS ARE ALREADY SATURATED FROM STORMS  
LAST NIGHT WHERE 1"+ AND UPWARDS OF 3" OF RAINFALL OCCURRED IN  
PORTIONS OF ONTONAGON AND HOUGHTON COUNTIES. BASED ON THE  
CURRENT SOIL CONDITIONS AND EXPECTED ADDITIONAL RAINFALL OF 1"  
TO POTENTIALLY OVER 2" A FLOOD WATCH HAS BEEN ISSUED OVER THE  
WEST FOR THIS AFTERNOON THROUGH TONIGHT FOR THE FLASH FLOOD  
THREAT.  
 

 
   
LONG TERM /THURSDAY NIGHT THROUGH WEDNESDAY/
 
 
ISSUED AT 307 PM EDT WED JUL 23 2025  
 
SHORTWAVE RIDGING WILL BUILD INTO THE REGION ON FRIDAY WITH THE  
UPPER LEVEL HIGH REMAINING OVER THE SOUTHEASTERN U.S AND ANOTHER  
TROUGH PUSHING INTO WESTERN CANADA. THIS WILL RESULT IN A DRY  
DAY TO END THE WORKWEEK. THEREAFTER THE UPPER LEVEL HIGH  
PRESSURE OVER THE SOUTHEAST BEGINS TO RETROGRADE TO THE WEST  
WHILE TROUGHING CONTINUES TO AFFECT MUCH OF CANADA. THE UPPER  
GREAT LAKES LOOKS LIKE IT WILL BE IN A FAVORABLE LOCATION FOR  
SHORTWAVES RUNNING AROUND THE RIDGE WITH WEST-NORTHWEST FLOW  
ALOFT. THIS WILL BRING THE CHANCE FOR SHOWERS AND THUNDERSTORM  
BACK INTO THE FORECAST THIS WEEKEND. TEMPERATURES WILL RUN  
ABOVE AVERAGE THIS WEEKEND WITH CONTINUED HUMID CONDITIONS.  
 

 
   
AVIATION /18Z TAFS THROUGH 18Z THURSDAY/
 
 
ISSUED AT 205 PM EDT WED JUL 23 2025  
 
THUNDERSTORMS CONTINUE TO POSE THE BIGGEST CHALLENGE TO THE FORECAST  
THIS AFTERNOON AND OVERNIGHT. MULTIPLE ROUNDS OF SHOWERS AND  
THUNDERSTORMS ARE EXPECTED TO MOVE THROUGH THE AREA. VFR CONDITIONS  
EARLY THIS AFTERNOON WILL DETERIORATE FROM WEST TO EAST THROUGH THIS  
EVENING. IFR CONDITIONS AND POSSIBLY LIFR CAN BE EXPECTED WITH ANY  
OF THE COMPLEXES OF SHOWERS AND THUNDERSTORMS. MOIST LOW LEVELS WILL  
ALSO RESULT IN AREAS OF LOW CLOUDS AND FOG DEVELOPING LATE  
TONIGHT INTO THE MORNING. JUST BEYOND THE TAF PERIOD IT LOOKS  
LIKE CONDITIONS SHOULD START TO IMPROVE WITH CEILINGS LIFTING  
AND ANY REMAINING SHOWERS EXITING THE AREA.  
 

 
   
MARINE
 
 
ISSUED AT 307 PM EDT WED JUL 23 2025  
 
WINDS GENERALLY OUT OF THE SOUTH MAY CONTINUE TO GUST TO AROUND  
20KTS IN THE EASTERN HALF OF THE LAKE THE REST OF TODAY AND INTO THE  
FIRST HALF OF THE NIGHT WITH LOW PRESSURE TROUGHING OVER THE GREAT  
LAKES. ADDITIONAL ROUNDS OF SHOWERS AND THUNDERSTORMS ARE EXPECTED  
ACROSS THE LAKE THIS EVENING THROUGH THURSDAY. SOME THE STORMS MAY  
BE STRONG TO SEVERE, BRINGING FREQUENT LIGHTNING, ERRATIC/DAMAGING  
WINDS (UP TO 30 PERCENT CHANCE), AND A WATERSPOUT CANNOT BE RULED  
OUT (ABOUT A 2 PERCENT CHANCE). AFTER TONIGHT, WINDS FALL BACK  
ACROSS THE LAKE AND REMAIN BELOW 20KTS THROUGH AT LEAST THE  
REMAINDER OF THIS WEEK.  
 

 
   
MQT WATCHES/WARNINGS/ADVISORIES
 
 
UPPER MICHIGAN...  
FLOOD WATCH THROUGH LATE TONIGHT FOR MIZ001>004-009-084.  
 
BEACH HAZARDS STATEMENT UNTIL 11 PM EDT THIS EVENING FOR  
MIZ014.  
 
LAKE SUPERIOR...  
NONE.  
LAKE MICHIGAN...  
NONE.  
 

 
 

 
 
SHORT TERM...NL  
LONG TERM...NL/TDUD  
AVIATION...NL  
MARINE...LC  
 
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