573  
FXUS63 KDLH 181946  
AFDDLH  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE DULUTH MN  
246 PM CDT FRI JUL 18 2025  
   
KEY MESSAGES  
 
- WIDESPREAD SHOWERS WITH EMBEDDED THUNDERSTORMS CONTINUE TODAY  
THROUGH TONIGHT. SEVERE THUNDERSTORMS ARE NOT EXPECTED.  
 
- PRIMARILY DRY WEATHER RETURNS THIS WEEKEND ONCE RAIN DEPARTS  
SATURDAY MORNING, THOUGH SMOKE ALOFT AND AT THE SURFACE SHOULD  
MAKE IT HAZY WITH REDUCED AIR QUALITY. HIGH TEMPS THIS  
WEEKEND WILL BE IN THE MID 70S TO AROUND 80.  
 
- AN ACTIVE PATTERN RETURNS TO THE AREA STARTING ON SUNDAY  
NIGHT, WITH MULTIPLE ROUNDS OF SHOWERS AND THUNDERSTORMS  
THROUGH NEXT WEEK.  
 
 
   
DISCUSSION  
 
ISSUED AT 245 PM CDT FRI JUL 18 2025  
 
TODAY - TONIGHT:  
 
GENERALLY ZONAL FLOW ALOFT TODAY WITH A WEAK 500 MB SHORTWAVE  
TROUGH MOVING THROUGH THE FLOW ACROSS THE NORTHLAND. PWATS OF  
1-1.5" MOVE IN WITH THIS SHORTWAVE TROUGH LATER THIS AFTERNOON  
INTO TONIGHT, WITH THE HIGHEST MOISTURE SOUTH OF US-2. EXPECT  
WIDESPREAD SHOWERS AND SOME EMBEDDED THUNDERSTORMS CURRENTLY  
OVER NORTHERN MINNESOTA AND LAKE SUPERIOR TO GRADUALLY  
OVERSPREAD THE REMAINDER OF THE NORTHLAND LATER THIS AFTERNOON  
THROUGH TONIGHT BEFORE EXITING FROM WEST TO EAST EARLY TO MID  
SATURDAY MORNING. DESPITE 0-6 KM SHEAR AROUND 50-55 KT,  
INSTABILITY (MUCAPE) SHOULD ONLY BE ON THE ORDER OF 200-700 J/KG  
ALONG AND SOUTH OF US-2, SO ANY THUNDERSTORMS THAT DO DEVELOP  
SHOULD BE LARGELY ISOLATED IN NATURE AND REMAIN NON-SEVERE.  
THERE IS SOME HIGHER DCAPE VALUES AND MODEST MID-LEVEL LAPSE  
RATES UP TO 6.5 C/KM THAT MAY GET INTO THE BRAINERD LAKES TO  
INLAND NW WI COUNTIES TONIGHT, SO CAN'T RULE OUT AN ISOLATED  
STORM IN THOSE LOCATIONS BECOMING STRONG WITH SMALL HAIL. STORMS  
SHOULD BE ELEVATED IN NATURE ABOVE THE NOCTURNAL SURFACE  
INVERSION, SO IT SHOULD BE DIFFICULT FOR ANY STRONGER WINDS TO  
MIX DOWN TO THE SURFACE. AS FOR RAIN, GENERALLY EXPECT MOST TO  
SEE LIGHT TO MODERATE RAIN, THROUGH SOME LOCALIZED AMOUNTS UP  
TO AROUND 1" OF TOTAL ACCUMULATIONS FROM TODAY THROUGH EARLY  
SATURDAY ARE POSSIBLE FOR LOCATIONS THAT SEE THE EMBEDDED  
THUNDERSTORMS AS SUGGESTED IN THE 12Z HREF LOCALIZED  
PROBABILITY-MATCHED MEAN 24-HOUR PRECIPITATION (7 AM TODAY-7 AM  
SATURDAY WINDOW).  
 
THIS WEEKEND:  
 
AFTER THE RAIN MOVES OUT SATURDAY MORNING, SOME CLEARING SKIES  
AND PREDOMINATELY DRY CONDITIONS SHOULD ARRIVE FOR MOST OF THIS  
WEEKEND. TEMPERATURES SHOULD BE AROUND AVERAGE IN THE MID 70S TO  
AROUND 80 DEGREES FOR SATURDAY AND SUNDAY. THERE IS SOME LOWER  
CONFIDENCE POTENTIAL FOR DECAYING SHOWERS FROM NORTH DAKOTA TO  
MOVE INTO NORTH-CENTRAL AND NORTHEAST MINNESOTA ON SUNDAY  
MORNING INTO EARLY AFTERNOON, BUT DRIER AIR NEAR THE SURFACE MAY  
KEEP THIS ACTIVITY AS VIRGA AND KEEP IT FROM REACHING THE  
GROUND. OTHERWISE, THE MAIN WEATHER CONCERN THIS WEEKEND WOULD  
BE CANADIAN WILDFIRE SMOKE SPREADING SOUTH INTO MUCH OF THE  
NORTHLAND SATURDAY AFTERNOON AND LINGERING INTO SUNDAY,  
RESULTING IN DETERIORATED AIR QUALITY AND HAZY  
CONDITIONS/REDUCED VISIBILITIES AT TIMES DUE TO THE SMOKE. AN  
AIR QUALITY ALERT (AQA) HAS BEEN ISSUED FOR ALL OF OUR NORTH-  
CENTRAL, EAST-CENTRAL, AND NORTHEAST MINNESOTA COUNTIES FROM 1  
PM SATURDAY THROUGH 9 AM ON MONDAY. THE AIR QUALITY IS FORECAST  
TO GET INTO THE "VERY UNHEALTHY" CATEGORY. MORE DETAILS CAN BE  
FOUND IN THE AQA. THIS SMOKE IS FORECAST TO EXIT BACK TO THE  
NORTH MONDAY MORNING AS SOUTHEAST SURFACE WINDS BECOME  
ESTABLISHED.  
 
SUNDAY NIGHT - MID NEXT WEEK:  
 
BROAD UPPER-LEVEL RIDGING BUILDS ACROSS MUCH OF THE CONUS DURING  
THIS TIMEFRAME AS A PROMINENT SUMMERTIME MID/UPPER-LEVEL HIGH  
PRESSURE CENTER BECOMES ESTABLISHED OVER THE SOUTHEASTERN  
CONUS. THIS WILL LEAVE THE UPPER MIDWEST AND NORTHLAND ON THE  
NORTHERN FRINGE OF THE UPPER-LEVEL RIDGE WHERE THE UPPER-LEVEL  
JET STREAM AND PERIODIC, EMBEDDED SHORTWAVE TROUGHS WILL BE  
MOVING ACROSS OUR VICINITY. THIS WILL BRING SEVERAL CHANCES FOR  
SHOWERS AND THUNDERSTORMS FROM SUNDAY NIGHT THROUGH TUESDAY  
NIGHT. SOME OF THESE ROUNDS COULD BECOME STRONG TO SEVERE STORMS  
WITH SOME HEAVY RAINFALL POTENTIAL AS RETURN FLOW OFF OF THE  
WESTERN GULF PUMPS 1.5"+ PWATS BACK INTO THE NORTHLAND, WITH  
DEWPOINTS CLIMBING INTO THE 60S TO NEAR 70F AND A BETTER  
INSTABILITY/SHEAR COMBINATION THAN WE ARE SEEING WITH THE  
CONVECTION TODAY. ONE THING OF NOTE IS THAT THE SYNOPTIC FORCING  
WITH THE SHORTWAVE TROUGHS IS RATHER NEBULOUS, SO THERE IS  
LOWER CONFIDENCE AT PINPOINTING EXACT TIMING, LOCATION, AND  
MAGNITUDE OF STRONG TO SEVERE STORM POTENTIAL EARLY NEXT WEEK AT  
THE MOMENT.  
 
LOOK FOR HUMIDITY AND TEMPERATURES TO INCREASE TOWARDS THE  
MIDDLE OF NEXT WEEK, WITH WIDESPREAD UPPER 70S TO MID 80S FOR  
TUESDAY AND WEDNESDAY ALONG WITH WIDESPREAD 60S TO NEAR 70F  
DEWPOINTS.  
 
LATE NEXT WEEK:  
 
THE PROMINENT UPPER-LEVEL RIDGE MAY BE SUPPRESSED SLIGHTLY  
FARTHER SOUTH LATER NEXT WORK WEEK ACCORDING TO SOME MID-RANGE  
ENSEMBLE GUIDANCE AND CLUSTER ANALYSIS. THIS SHOULD KEEP THE  
HOTTEST CONDITIONS SOUTH OF THE NORTHLAND, BUT UPPER 70S TO MID  
80S HIGH TEMPERATURES AND HIGHER HUMIDITY SHOULD LARGELY  
PERSIST. ADDITIONAL SHOWER AND THUNDERSTORM CHANCES CONTINUE AT  
TIMES FOR THE SECOND HALF OF NEXT WEEK AS PERIODIC MID/UPPER-  
LEVEL SHORTWAVE TROUGHS CONTINUE TO MOVE THROUGH THE NORTHERN  
CONUS.  
 
 
   
AVIATION /18Z TAFS THROUGH 18Z SATURDAY/  
 
ISSUED AT 1241 PM CDT FRI JUL 18 2025  
 
WIDESPREAD SHOWERS WITH A FEW EMBEDDED STORMS OVER NORTH-CENTRAL  
AND NORTHEAST MINNESOTA THIS AFTERNOON WILL SPREAD SOUTHEAST  
ACROSS THE AREA THIS EVENING INTO TONIGHT BEFORE EXITING WEST TO  
EAST EARLY TO MID SATURDAY MORNING. CEILINGS WILL BE VFR FOR  
MOST TERMINALS UNTIL THE EVENING, THROUGH SOME PERIODIC MVFR  
CEILINGS AND VISIBILITIES IN THE RAIN/FEW EMBEDDED STORMS CANNOT  
BE RULED OUT. CEILINGS AND VISIBILITIES DECREASE EVEN MORE THIS  
EVENING INTO EARLY SATURDAY MORNING, WITH WIDESPREAD LIFR  
CONDITIONS FOR MOST TERMINALS STILL EXPECTED FOR AREAS SOUTH OF  
INL. CONDITIONS SHOULD IMPROVE MID TO LATE SATURDAY MORNING AS  
CLOUDS SCATTER OUT FROM NORTH TO SOUTH, BUT CANADIAN WILDFIRE  
SMOKE IS POISED TO MOVE INTO THE NORTHLAND STARTING SATURDAY  
AFTERNOON, WHICH SHOULD LEAD TO REDUCED VISIBILITIES SPREADING  
IN FROM NORTH TO SOUTH NEAR OR JUST AFTER THE END OF THE CURRENT  
TAF PERIOD.  
 
 
   
MARINE /FOR NEAR SHORE WATERS OF WESTERN LAKE SUPERIOR/  
 
ISSUED AT 245 PM CDT FRI JUL 18 2025  
 
GENERALLY LIGHT WINDS TODAY, WITH SOME NORTHEAST WINDS OF 5 TO  
15 KNOTS THIS EVENING INTO EARLY SATURDAY MORNING ALONG WITH 1-2  
FOOT WAVES. WINDS THEN REMAIN LIGHT AND VARIABLE INTO SUNDAY  
MORNING BEFORE TURNING NORTHEASTERLY AGAIN WITH WINDS OF 5-15  
KNOTS SUNDAY AFTERNOON AND EVENING, STRONGEST IN THE SOUTHWEST  
ARM OF LAKE SUPERIOR.  
 
RAIN SHOWERS WITH EMBEDDED ISOLATED THUNDERSTORMS PERSIST OFF  
AND ON INTO TONIGHT. NO SEVERE THUNDERSTORMS ARE EXPECTED,  
THOUGH THERE MAY OCCASIONALLY BE LOCALLY GUSTY WINDS AND CLOUD-  
TO-WATER LIGHTNING. SOME REDUCED VISIBILITIES WITH AND BEHIND  
THE RAIN IN FOG ALSO DEVELOP LATER THIS EVENING INTO EARLY  
SATURDAY MORNING. ADDITIONAL CHANCES FOR THUNDERSTORMS RETURN  
EARLY NEXT WEEK.  
 
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...ROTHSTEIN  
AVIATION...ROTHSTEIN  
MARINE...ROTHSTEIN  
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