599  
FXUS63 KDLH 110536  
AFDDLH  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE DULUTH MN  
1236 AM CDT FRI JUL 11 2025  
   
KEY MESSAGES  
 
- SPOTTY SHOWERS AND THUNDERSTORMS THROUGH TONIGHT ALONG WITH  
SOME FOG DEVELOPING OVERNIGHT.  
 
- SHOWERS AND THUNDERSTORMS ARE EXPECTED AT TIMES FRIDAY AND  
FRIDAY EVENING. A FEW STRONG TO SEVERE STORMS ARE POSSIBLE  
ALONG WITH HEAVY RAIN THAT COULD LEAD TO LOCALIZED FLOODING.  
 
- OCCASIONAL RAIN CHANCES INTO NEXT WEEK WITH POTENTIAL FOR  
THUNDERSTORMS ON TUESDAY.  
 
 
   
DISCUSSION  
 
ISSUED AT 1255 PM CDT THU JUL 10 2025  
 
THIS AFTERNOON AND TONIGHT:  
 
AN INITIAL ROUND OF SHOWERS AND STORMS THIS MORNING HAS CAPPED OFF  
CONVECTION FROM DEVELOPING THIS AFTERNOON FOR THE MOST PART. STORMS  
HAD BEEN LARGELY REDEVELOPING ALONG THEIR OUTFLOW BOUNDARIES. CAMS  
HAVE HAD A REALLY HARD TIME KEEPING UP WITH THIS ACTIVITY, AND WITH  
A SIMILAR FAVORABLE INSTABILITY BUT LOW WIND SHEAR ENVIRONMENT  
EXPECTED TO PERSIST INTO TONIGHT, THE FORECAST CONFIDENCE FOR  
ADDITIONAL SHOWERS AND THUNDERSTORMS IS RATHER LOW. WE SHOULD HAVE  
CONTINUING WARM AIR ADVECTION AND WE ALREADY HAVE PLENTY OF MOISTURE  
IN PLACE (PWATS AROUND 1.0"-1.5"). THE QUESTION OF WHERE THE CAP MAY  
BUST IN AND AROUND OUR REGION IS STILL IN QUESTION, AND WITHOUT MUCH  
FOR ORGANIZED FRONTS AROUND UNTIL WE GET A COLD FRONT FRIDAY  
EVENING, WE CAN EXPECT MORE OF THE SAME SHOWER AND STORM ACTIVITY  
THROUGH TONIGHT. THIS MEANS THAT SPATIAL COVERAGE OF ANY  
SHOWERS/STORMS SHOULD BE GENERALLY ISOLATED, BUT ANYTHING THAT POPS  
OFF COULD DEVELOP AN OUTFLOW BOUNDARY THAT COULD KICK OFF MORE  
STORMS AROUND IT. BUT RIGHT NOW, IT LOOKS LIKE THE BEST INSTABILITY  
(MUCAPE ~2-3 KJ/KG) MAY CONFINE ITSELF TO NORTH-CENTRAL MINNESOTA,  
THUS GIVING THAT AREA THE BEST CHANCE (~60%) FOR STORMS LATER THIS  
EVENING INTO TONIGHT. WITH WIND SHEAR TOPPING OUT AROUND 15-25 KT,  
SEVERE THREATS ARE GOING TO BE LIMITED TO SOME BRIEF LARGE HAIL AND  
MAYBE SOME GUSTY WINDS (A ~5% CHANCE ISOLATED THREAT, PER SPC  
OUTLOOKS).  
 
ANOTHER THING WE'VE BEEN OBSERVING WITH THIS MORNING'S STORMS IS  
SOME PRETTY HEFTY RAINFALL RATES AROUND OR PERHAPS SLIGHTLY  
EXCEEDING AN INCH PER HOUR AS STORMS THAT FORM (WITH PLENTY OF  
MOISTURE TO WORK WITH) SIMPLY AREN'T MOVING VERY FAST. WPC HAS  
OUTLINED A MARGINAL RISK FOR RAINFALL EXCEEDING FLASH FLOOD GUIDANCE  
THROUGH TONIGHT. IN OTHER WORDS, WHILE FLOODING IS GENERALLY  
UNLIKELY, THERE'S ~5% CHANCE THAT ANY STORMS THAT FORM COULD PRODUCE  
SOME LOCALIZED MINOR FLOODING.  
 
FRIDAY AND SATURDAY:  
 
GOING INTO FRIDAY, A BIT OF RINSE AND REPEAT WITH THE STORM CHANCES  
EXCEPT THAT WE WILL HAVE A BIT MORE OF A FOCUS FOR CONVECTION OUT  
AHEAD OF THE SLOWLY APPROACHING COLD FRONT FROM THE NORTHWEST. SHEAR  
LOOKS TO REMAIN ON THE LOW SIDE, BUT INSTABILITY SHOULD REMAIN IN  
PLACE AND PWATS MAY INCREASE A BIT TO AROUND 1.5" TO NEARLY 2.0". WE  
ALSO MIGHT HAVE A BRIEF WINDOW FRIDAY LATE AFTERNOON AND EARLY  
EVENING WHERE THERE COULD BE A BRIEF COLLABORATION BETWEEN  
INCREASING WIND SHEAR JUST AHEAD OF THE COLD FRONT AND LINGERING  
INSTABILITY TO INCREASE CHANCES FOR SEVERE WEATHER SLIGHTLY. THERE  
MAY BE ENOUGH DRY AIR ALOFT TO PROMOTE THE LARGE HAIL THREAT AND  
PERHAPS SOME DAMAGING WINDS. IT'S TRICKY TO SAY HOW BIG OF HAIL  
THERE COULD BE SINCE THERE ARE GOING TO BE SOME CONFLICTING  
INGREDIENTS, LIKE HIGH FREEZING HEIGHTS (HAIL MELTS MORE AS IT  
FALLS) BUT ALSO PLENTY OF INSTABILITY (UP TO 2-3 KJ/KG; MAKES FOR  
BIGGER HAIL ALOFT). UNCERTAINTY IN HOW MUCH MOISTURE ENTRAINMENT  
THERE WILL BE ALSO LENDS UNCERTAINTY IN POTENTIAL HAIL SIZE, BUT ALL  
THINGS CONSIDERED, PERHAPS UP TO AROUND 1.5" IN DIAMETER COULD BE  
POSSIBLE IN THE LARGEST OF STORMS. ANY THAT DO FORM TO THIS  
INTENSITY SHOULD BE PRETTY SHORT-DURATION WITH THE LOW WIND SHEAR  
THOUGH.  
 
RAINFALL IN GENERAL SHOULD BE A BIT MORE WIDESPREAD WITH HIGHER  
MOISTURE AND PRE-FRONTAL FORCING. AT THIS TIME, THERE ARE NOT ANY  
HIGH SIGNALS IN THE MODELS FAVORING SUBSTANTIAL RAINFALL TOTALS  
(E.G. NBM PROBABILITIES FOR 2"+ ARE ONLY UP TO ~10%). THAT  
SAID, WHAT WE'VE OBSERVED WITH STORMS THIS MORNING IS THAT WHERE  
THEY DO FORM, THEY ARE CERTAINLY CAPABLE OF DROPPING A LOT OF  
WATER. THUS, A NONZERO THREAT FOR FLASH FLOODING DOES EXIST. WPC  
CURRENTLY HAS UPGRADED MOST OF THE REGION TO A SLIGHT RISK FOR  
RAINFALL EXCEEDING FLASH FLOOD GUIDANCE (~15% CHANCE). LOCALIZED  
MINOR FLOODING IS POSSIBLE, AND IF THERE IS AN AREA OF STORMS  
THAT DEVELOPS AND PERSISTS, THEN THERE COULD STILL BE POTENTIAL  
FOR RAINFALL TOTALS UPWARDS OF 3-4". THERE IS VERY LOW  
PREDICTABILITY OF WHERE OR IF THIS WILL HAPPEN, EVEN AT THIS  
SHORT TIME WINDOW, SO FOR NOW, KEEP AN EYE ON THE FORECAST AND  
MONITOR CONDITIONS FRIDAY AFTERNOON AND EVENING IN CASE SUCH A  
SCENARIO PLAYS OUT SOMEWHERE IN THE NORTHLAND.  
 
SHOWERS AND STORMS SHOULD DECREASE IN OVERALL COVERAGE AND  
INTENSITY FRIDAY NIGHT AS DIURNAL INSTABILITY GOES AWAY AND THE  
FRONT PASSES THROUGH. IT'S STILL LOOKING LIKE WE COULD SEE SOME  
WRAPAROUND SHOWERS AND PERHAPS SOME NON-SEVERE STORMS ON  
SATURDAY WITH A TROUGH PASSING THROUGH OVERHEAD, THOUGH DRIER  
AIR FILTERING IN MAY LIMIT THIS POTENTIAL. ANY LINGERING SHOWERS  
OR STORMS ARE NOT EXPECTED TO PRODUCE SUBSTANTIAL RAIN.  
 
SUNDAY INTO NEXT WEEK:  
 
BROAD BUT LOW AMPLITUDE RIDGING DEVELOPS GOING INTO SUNDAY, SO  
IT'S LOOKING LIKE A LARGELY QUIET WEATHER DAY, AND ALSO A BIT  
WARM WITH HIGHS IN THE 80S. THERE ARE SOME HINTS THAT A WEAK  
TROUGH COULD PASS THROUGH AROUND MONDAY NIGHT INTO MONDAY  
MORNING, BRINGING SOME SHOWER/STORM CHANCES, BUT NOT ALL MODELS  
ARE ON BOARD WITH THIS. A WARM AIR ADVECTION REGIME LOOKS LIKE  
IT'LL PERSIST GOING INTO TUESDAY, THEN MAYBE AN UPPER-LEVEL  
TROUGH WITH A COLD FRONT GOING INTO WEDNESDAY. TUESDAY MIGHT BE  
A DAY TO WATCH FOR SOME STORM POTENTIAL WITH INCREASING  
MOISTURE, INSTABILITY, AND SHEAR. IT'S TOO EARLY TO SAY IF THERE  
COULD BE ANY SEVERE WEATHER, BUT THIS LOOKS TO BE THE NEXT BEST  
CHANCE IN THE NEAR FUTURE AFTER FRIDAY'S STORMS. SOME COOLER  
TEMPERATURES MAY FOLLOW WEDNESDAY INTO THURSDAY.  
 
 
   
AVIATION /06Z TAFS THROUGH 06Z SATURDAY/  
 
ISSUED AT 1229 AM CDT FRI JUL 11 2025  
 
FOG AT HIB HAS FORMED, AND VISIBILITIES SHOULD BE UP AND DOWN  
FOR THE REMAINDER OF THE NIGHT. CONDITIONS SHOULD LARGELY REMAIN  
MVFR/IFR, BUT HAVE ADDED A TEMPO SINCE THIS TERMINAL IN  
PARTICULAR HAS A HABIT OF REACHING BELOW MINIMUMS. FOG IS ALSO  
POSSIBLE FURTHER EAST AT DLH AND HYR. SOME AWOS'S IN NORTHWEST  
WISCONSIN HAVE SEEN SOME MVFR VISIBILITIES BEFORE CLEARING  
AGAIN, SO HAVE THAT IN A TEMPO FOR HYR AS WELL. STORMS ARE  
EXPECTED AGAIN TODAY, AND A COLD FRONT WILL MOVE THROUGH LATER  
TODAY, WITH THE HIGHEST PROBABILITIES FOR STORMS AS IT PASSES.  
HOWEVER, THERE WILL BE PLENTY OF FUEL FOR STORMS TO INITIATE  
AHEAD OF TIME, SO CANNOT RULE THAT OUT. PROB30S HAVE BEEN ADDED  
WHERE STORMS COULD FORM AHEAD OF THE COLD FRONT. MODELS ARE  
HINTING AT FOG AGAIN TOMORROW NIGHT WHERE THERE IS RAINFALL, AND  
WILL BE REFLECTED IN THE NEXT TAF SET AT 12Z.  
 
 
   
MARINE /FOR NEAR SHORE WATERS OF WESTERN LAKE SUPERIOR/  
 
ISSUED AT 334 PM CDT THU JUL 10 2025  
 
EXPECT OCCASIONALLY BREEZY EAST TO NORTHEAST WINDS THROUGH  
AROUND SUNSET. GUSTS UP TO 15 TO 20 KT ARE POSSIBLE AT TIMES,  
BUT ARE EXPECTED TO DECREASE QUICKLY EARLY THIS EVENING. WINDS  
ARE EXPECTED TO BECOME MORE LIGHT AND VARIABLE ON FRIDAY, THOUGH  
PREDOMINANTLY REMAINING NORTHEASTERLY. PERIODS OF RAIN AND  
THUNDERSTORMS ARE EXPECTED, MAINLY IN THE AFTERNOON AND EVENING  
HOURS, WHICH COULD LEAD TO GUSTY AND ERRATIC WINDS AT TIMES.  
OTHER HAZARDS INCLUDE HEAVY RAIN, CLOUD TO WATER LIGHTNING, AND A  
SMALL CHANCE FOR LARGE HAIL. AFTER A COLD FRONT PASSES THROUGH  
FRIDAY NIGHT, WINDS ARE EXPECTED TO SHIFT TO WESTERLY TO  
SOUTHWESTERLY. SOME GUSTS UP TO 15 TO 20 KT ARE POSSIBLE ON  
SATURDAY AS WELL AS SUNDAY.  
 
FOR THE OPEN WATER DISCUSSION, REFER TO THE NWS MARQUETTE AREA  
FORECAST DISCUSSION AT WEATHER.GOV/MQT.  
 
 
   
DLH WATCHES/WARNINGS/ADVISORIES  
 
MN...NONE.  
WI...NONE.  
MARINE...NONE.  
 
 
 
 
 
DISCUSSION...JDS  
AVIATION...KML  
MARINE...JDS  
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