762  
FXUS63 KDLH 171126  
AFDDLH  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE DULUTH MN  
626 AM CDT MON AUG 17 2026  
   
KEY MESSAGES  
 
- PATCHY FOG, OCCASIONALLY BECOME LOCALLY DENSE, IS EXPECTED TO  
DISSIPATE AFTER SUNRISE. CLOUD COVER WILL BE INCREASING LATER  
THIS MORNING INTO THE AFTERNOON.  
 
- SHOWERS AND THUNDERSTORMS ARRIVE THIS AFTERNOON AND EVENING  
ALONG A COLD FRONT. A FEW STORMS MAY BE STRONG TO SEVERE,  
ESPECIALLY IN THE BRAINERD LAKES AREA. POTENTIAL HAZARDS  
INCLUDE DAMAGING WINDS UP TO 60 MPH AND LARGE HAIL UP TO 1  
INCH IN DIAMETER.  
 
- DRY AND COOLER WEATHER IS FORECAST FOR TUESDAY INTO WEDNESDAY,  
WITH ADDITIONAL RAIN CHANCES AND SLIGHTLY WARMER TEMPS LATE IN  
THE WORKWEEK.  
 
 
   
UPDATE  
 
ISSUED AT 422 AM CDT MON AUG 17 2026  
 
MOSTLY CLEAR SKIES ALLOWING FOR DIURNAL COOLING COMBINED WITH LIGHT  
WINDS HAS PRODUCED PATCHY FOG EARLY THIS MORNING. VISIBILITY  
HAS BEEN TRENDING SLIGHTLY LOWER SINCE THE PREVIOUS DISCUSSION  
UPDATE, WITH ISOLATED AREAS OF 1/2 MILE VISIBILITY OCCASIONALLY  
OCCURRING. WILL CONTINUE TO HOLD OFF ON ISSUING A DENSE FOG  
ADVISORY THIS MORNING DUE TO THE DENSE FOG COVERAGE BEING TOO  
ISOLATED AND DURATION BEING TOO INTERMITTENT. FOG IS STILL  
EXPECTED TO DISSIPATE JUST AFTER SUNRISE THIS MORNING AS DIURNAL  
HEATING BEGINS.  
 
THE FORECAST FOR THIS AFTERNOON IS STILL ON TRACK WITH THE PREVIOUS  
UPDATE. TIMING FOR SHOWERS AND THUNDERSTORMS DEVELOPING ALONG AN  
APPROACHING COLD FRONT IS STILL EXPECTED TO BE THE AFTERNOON INTO  
THE EARLY EVENING, WHICH WILL COINCIDE WITH PEAK DIURNAL HEATING.  
THE SOUTHWESTERN PORTION OF THE CWA REMAINS UNDER A MARGINAL RISK  
(LEVEL 1 OUT OF 5) OUTLOOK FROM SPC TODAY, WITH A SMALL NORTHWARD  
EXPANSION OF THE MARGINAL RISK OCCURRING THIS MORNING. POTENTIAL  
SEVERE HAZARDS WILL BE DAMAGING WINDS UP TO 60 MPH AND LARGE HAIL UP  
TO 1 INCH IN DIAMETER.  
 
FOLLOWING THE COLD FRONTAL PASSAGE TONIGHT, COOLER TEMPERATURES  
FILTER INTO THE CWA FOR TUESDAY INTO WEDNESDAY. FROST IS NOT  
ANTICIPATED ON TUESDAY NIGHT INTO EARLY WEDNESDAY MORNING, BUT  
EXPECT CHILLY LOW TEMPERATURES IN THE 40S WITH A FEW UPPER 30S  
POSSIBLE. THE FORECAST FOR THE LATTER HALF OF THE WEEK REMAINS  
ON TRACK SINCE THE PREVIOUS FORECAST UPDATE.  
 
 
   
DISCUSSION  
 
ISSUED AT 155 PM CDT SUN AUG 16 2026  
 
PLENTY OF CLOUDS WITH A FEW EMBEDDED SPRINKLES IS THE STORY OF  
THIS SUNDAY. DRIER AIR IS FILTERING IN FROM THE NORTHWEST WITH A  
SURFACE HIGH MOVING IN FROM THE WEST. THEREFORE, EXPECT  
GRADUALLY CLEARING SKIES THIS AFTERNOON AND MOSTLY CLEAR SKIES  
OVERNIGHT. WE WILL PROBABLY GET SOME FOG TO DEVELOP WITH GOOD  
RADIATIONAL COOLING CONDITIONS. MODELS ARE PRETTY SOLID ON  
HAVING FOG IN THE USUAL LOW-LYING INLAND AREAS. THE PROBABILITY  
FOR VISIBILITIES LESS THAN 1 MILE ARE GENERALLY 20% OR LESS, SO  
WE WILL PROBABLY SEE SOME PATCHY DENSE FOG, BUT PERHAPS NOT  
ENOUGH COVERAGE TO WARRANT ANY DENSE FOG ADVISORIES. EXPECT FOG  
TO LIFT/MIX OUT JUST AFTER SUNRISE MONDAY MORNING.  
 
MONDAY AFTERNOON INTO MONDAY NIGHT, ANOTHER COLD FRONT IS  
EXPECTED TO MAKE ITS WAY THROUGH FROM NORTHWEST TO SOUTHEAST.  
WE'LL HAVE SUFFICIENT MOISTURE FOR SOME THUNDERSTORMS WITH PWATS  
IN THE 1-1.5" RANGE. GOOD SYNOPTIC SUPPORT FOR LIFT WITH THE  
FRONT ITSELF AND AN UPPER-LEVEL TROUGH ALOFT. CONVECTIVE  
PARAMETERS ARE SO-SO FOR ANY STRONG/SEVERE STORMS. THE TIMING OF  
THIS HAS TRENDED EARLIER SUCH THAT WE MAY CATCH THE PEAK DIURNAL  
HEATING MONDAY AFTERNOON AND END UP WITH ~1000 J/KG OR SO OF  
MUCAPE, AT LEAST IN NORTHEAST MINNESOTA. NOT MUCH FOR LOW-LEVEL  
DIRECTIONAL SHEAR WITH SOUTHWEST FLOW EXPECTED AHEAD OF THE  
FRONT. SOME DRIER AIR ALOFT AHEAD OF THE FRONT COULD PRODUCE A  
SMALL RISK FOR STRONG WIND GUSTS. ALL SAID, WE'LL BE LOOKING AT  
WIDESPREAD SHOWERS AND STORMS LIKELY MONDAY AFTERNOON AND NIGHT,  
GENERALLY WEAKENING A BIT AS THEY MOVE INTO NORTHWEST  
WISCONSIN. A FEW STORMS COULD BE ON THE STRONG SIDE WITH SOME  
SMALL HAIL AND GUSTY WINDS, AND A STRAY SEVERE STORM CAN'T BE  
RULED OUT WITH LOW-END STRONG WINDS OR QUARTER SIZE HAIL BEING  
THE MAIN THREATS.  
 
EXPECT THE FRONT TO BE OUT OF HERE TUESDAY MORNING, LEAVING US  
WITH NORTHWEST FLOW AND SOME SLIGHTLY COOLER TEMPERATURES (HIGHS  
IN THE 70S). TUESDAY NIGHT MIGHT BE ON THE CHILLY SIDE WITH LOWS  
IN THE 40S LIKELY AND PERHAPS SOME STRAY UPPER 30S NOT OUT OF  
THE QUESTION FOR THE USUAL COLD SPOTS. HIGH PRESSURE STICKS  
AROUND INTO WEDNESDAY, KEEPING THE WEATHER QUIET. SOUTHERLY  
RETURN FLOW WILL LIKELY DEVELOP THURSDAY, AND WE'LL BE WATCHING  
FOR ANOTHER COLD FRONT TO BE MAKING ITS WAY HERE BY AROUND  
FRIDAY. WE COULD SEE ANOTHER ROUND OF SHOWERS AND STORMS WITH  
THIS. AT THIS TIME, CONVECTIVE PARAMETERS LOOK RATHER DULL FOR  
ANYTHING STRONG/SEVERE, BUT THAT COULD CHANGE.  
 
THE PATTERN IS LOOKING VERY PRE-FALL NEXT WEEKEND WITH NORTHWEST  
FLOW FOLLOWING THE COLD FRONT. SOME LINGERING INSTABILITY  
SHOWERS CAN'T BE RULED OUT SATURDAY, BUT OTHERWISE THE WEATHER  
LOOKS PRETTY QUIET. ONE MIGHT BE TEMPTED TO CALL THIS FALL-LIKE  
WEATHER, BUT WITH TEMPERATURES STILL LOOKING TO BE IN THE 70S TO  
AROUND 80 FOR HIGHS, IT SHOULD STILL BE FEELING MORE LIKE LATE-SUMMER  
WEATHER.  
 
 
   
AVIATION /12Z TAFS THROUGH 12Z TUESDAY/  
 
ISSUED AT 626 AM CDT MON AUG 17 2026  
 
PATCHY FOG WILL BE CLEARING OVER THE NEXT COUPLE HOURS AS DAYTIME  
HEATING BEGINS AND WEST-SOUTHWEST WINDS INCREASE. A COLD FRONT WILL  
BE SWEEPING THROUGH THIS AFTERNOON AND EVENING, BRINGING A LINE OF  
SCATTERED TO WIDESPREAD SHOWERS AND THUNDERSTORMS. A FEW STORMS MAY  
BECOME STRONG, ESPECIALLY AROUND THE BRAINERD LAKES, CAPABLE OF  
PRODUCING SMALL HAIL AND GUSTY WINDS. AFTER THE RAIN EXITS TONIGHT,  
ANOTHER ROUND OF PATCHY FOG WILL BE POSSIBLE AS WINDS EASE  
OVERNIGHT.  
 
 
   
MARINE /FOR NEARSHORE WATERS OF WESTERN LAKE SUPERIOR/  
 
ISSUED AT 422 AM CDT MON AUG 17 2026  
 
BREEZY SOUTHWEST WINDS AHEAD OF A COLD FRONT ARE EXPECTED THIS  
AFTERNOON ALONG THE NORTH SHORE. THE SMALL CRAFT ADVISORY THAT WAS  
IN EFFECT FROM GRAND MARAIS TO GRAND PORTAGE HAS BEEN EXPANDED TO  
NOW INCLUDE NEARSHORE WATERS FROM GRAND MARAIS TO SILVER BAY, AS  
THERE IS THE POTENTIAL FOR WIND GUSTS TO 25 KNOTS FOR SEVERAL HOURS  
THIS AFTERNOON.  
 
SHOWERS AND THUNDERSTORMS ARRIVE ALONG THE AFOREMENTIONED COLD FRONT  
THIS AFTERNOON AND EVENING, ALTHOUGH SEVERE THUNDERSTORMS ARE NOT  
EXPECTED. EXPECT WINDS TO SHIFT TO THE NORTHWEST TONIGHT FOLLOWING  
THE COLD FRONT, WITH WINDS GENERALLY TRENDING LIGHTER HEADING INTO  
MID-WEEK AS HIGH PRESSURE BUILDS.  
 
FOR THE OPEN WATER DISCUSSION, REFER TO THE NWS MARQUETTE AREA  
FORECAST DISCUSSION AT WEATHER.GOV/MQT.  
 
 
   
FIRE WEATHER  
 
ISSUED AT 422 AM CDT MON AUG 17 2026  
 
CLEAR SKIES WILL START OFF TODAY, WITH SOUTHWEST WINDS GUSTING 15 TO  
20 MPH THIS AFTERNOON AHEAD OF AN APPROACHING COLD FRONT. EXPECT  
CLOUD COVER TO INCREASE FROM WEST TO EAST THROUGH THE DAY, WITH  
NORTHWEST WI SEEING THE DRIEST MIN RH THIS AFTERNOON IN THE 33-39%  
RANGE DUE TO CLOUDS NOT ARRIVING UNTIL LATER IN THE DAY. SCATTERED  
TO WIDESPREAD SHOWERS AND THUNDERSTORMS WILL BE MOVING THROUGH THIS  
AFTERNOON AND EVENING, WITH WETTING RAINS OF 0.25" OR GREATER BEING  
HIT OR MISS UNDER INDIVIDUAL THUNDERSTORM CORES. A FEW STORMS MAY  
BECOME STRONG TO SEVERE, ESPECIALLY IN NORTH-CENTRAL MN, WITH GUSTY  
AND ERRATIC WIND GUSTS UP TO 60 MPH AND HAIL TO 1" IN DIAMETER BEING  
PRIMARY HAZARDS.  
 
WINDS SHIFT TO THE NORTHWEST TONIGHT AND HIGH PRESSURE BUILDS ON  
TUESDAY INTO WEDNESDAY, BRINGING COOLER TEMPERATURES AND DRIER MIN  
RH FOR MID-WEEK. WHILE CRITICALLY DRY MIN RH IS NOT ANTICIPATED AT  
THIS TIME, AREAS OF MIN RH AS LOW AS 30% WILL BE POSSIBLE EACH  
AFTERNOON FROM TUESDAY THROUGH THURSDAY. ADDITIONAL CHANCES FOR  
SHOWERS AND THUNDERSTORMS ARRIVE LATE THURSDAY INTO FRIDAY AS  
ANOTHER COLD FRONT MOVES INTO THE AREA.  
 
SEE THE FIRE WEATHER FORECAST PRODUCT FOR A MORE THOROUGH  
BREAKDOWN OF FIRE WEATHER CONDITIONS.  
 
 
   
DLH WATCHES/WARNINGS/ADVISORIES  
 
MN...NONE.  
WI...NONE.  
MARINE...SMALL CRAFT ADVISORY FROM NOON TODAY TO 10 PM CDT THIS EVENING  
FOR LSZ140>142.  
 
 
 
 
 
UPDATE...UNRUH  
DISCUSSION...JDS  
AVIATION...UNRUH  
MARINE...UNRUH  
FIRE WEATHER...UNRUH  
CLICK HERE TO GO TO PREVIOUS BULLETINS.
The Nexlab MN Page
The Nexlab WI Page
Main Text Page