754  
FXUS63 KDLH 171133  
AFDDLH  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE DULUTH MN  
633 AM CDT THU SEP 17 2026  
   
KEY MESSAGES
 
 
- AREAS OF DENSE FOG ARE POSSIBLE THIS MORNING. A DENSE FOG  
ADVISORY IS IN EFFECT UNTIL 10 AM FOR PORTIONS OF CENTRAL AND  
NORTH-CENTRAL MINNESOTA.  
 
- ANOTHER ROUND OF SHOWERS WILL SPREAD ACROSS THE REGION EARLY  
FRIDAY AND LINGER INTO SATURDAY MORNING. THE HEAVIEST RAINFALL  
(40-60% OF 1") WILL BE SOUTH OF A LINE FROM BRAINERD TO  
SANDSTONE TO HAYWARD TO PARK FALLS.  
 
- DANGEROUS SWIMMING CONDITIONS EXPECTED FOR THE BEACHES OF THE  
TWIN PORTS FRIDAY AND SATURDAY THEN AGAIN SUNDAY AND MONDAY  
AFTERNOONS AND EVENING.  
 

 
   
DISCUSSION
 
 
ISSUED AT 337 AM CDT THU SEP 17 2026  
 
TODAY AND TONIGHT...  
 
LIGHT RAIN LINGERED OVER NORTHWEST WISCONSIN EAST OF A LINE  
FROM SPOONER TO MERCER. ANOTHER BAND OF SHOWERS WAS ADVANCING  
EAST-SOUTHEAST ALONG THE NORTH DAKOTA/MANITOBA BORDER EAST INTO  
NORTHWEST ONTARIO. BETWEEN THESE TWO AREAS OF PRECIPITATION A  
WEDGE OF CLEAR SKIES WAS FOUND. AREAS OF FOG ARE ANTICIPATED  
THIS MORNING AS WINDS BECOME LIGHT. THE LOWEST VISIBILITY WILL  
BE FOUND OVER AREAS THAT RECEIVED RAINFALL WEDNESDAY AFTERNOON  
AND EVENING. WE WILL MONITOR TRENDS. A DENSE FOG ADVISORY MAY  
BECOME NECESSARY.  
 
THE LIGHT RAIN OVER NORTHWEST WISCONSIN WILL PUSH OUT OF OUR  
AREA BY 7 AM WHILE THE NORTHERN BAND OF SHOWERS SAGS SOUTHWARD  
INTO THE BORDERLANDS AND GRADUALLY DISSIPATES BY 10 AM.  
OTHERWISE EXPECT MOSTLY SUNNY TO PARTLY CLOUDY SKIES TODAY.  
HIGHS WILL REACH THE MIDDLE 60S ALONG THE CANADIAN BORDER TO THE  
MIDDLE 70S IN THE ST. CROIX RIVER VALLEY. CLOUDS SPREAD  
NORTHWARD TONIGHT AHEAD OF AN APPROACHING LOW PRESSURE SYSTEM.  
RAIN CHANCES WILL LIKELY HOLD OFF UNTIL AFTER 7 AM FRIDAY DUE TO  
THE INFLUENCE OF HIGH PRESSURE MOVING EASTWARD ACROSS SOUTHERN  
MANITOBA INTO NORTHWEST ONTARIO. MORE ON THAT BELOW.  
 
FRIDAY AND SATURDAY...  
 
SURFACE LOW PRESSURE AND ASSOCIATED SHORTWAVE TROUGH WILL  
PROPAGATE EASTWARD FROM THE SOUTH DAKOTA/NEBRASKA BORDER TO NEAR  
SOUTHERN LAKE MICHIGAN BY SATURDAY EVENING. A WARM FRONT WILL  
LIFT NORTHWARD ACROSS IOWA TO NEAR THE MINNESOTA BORDER AND  
STRETCH EAST INTO SOUTHERN WISCONSIN BY FRIDAY EVENING.  
ISENTROPIC ASCENT OVER THE WARM FRONTAL ZONE WILL PRODUCE A  
BROAD AREA OF PRECIPITATION OVER SOUTHERN AND CENTRAL MINNESOTA  
STRETCHING INTO NORTHWEST WISCONSIN ON FRIDAY. THE INFLUENCE OF  
THE NORTHERN SURFACE HIGH PRESSURE WILL BE MOST NOTICEABLE  
THROUGH REINFORCING DRY AIR FROM NORTH TO SOUTH UNDERCUTTING THE  
PRECIPITATION. RADAR ECHOES ARE LIKELY TO OVER-REPRESENT THE  
NORTHWARD EXTENT OF PRECIPITATION AS THE DRY AIR EVAPORATES THE  
RAIN BEFORE IT CAN REACH THE GROUND. WE CONTINUED THE PREVIOUS  
SHIFT'S CONCEPT OF TIGHTENING THE QPF AND POP GRADIENT OVER  
CENTRAL MINNESOTA INTO NORTHERN WISCONSIN.  
 
NBM PROBABILITIES SUPPORT THE TIGHT GRADIENT OF PRECIP AND  
POPS. THE NBM PROBABILITY OF MORE THAN 1 INCH OF RAIN IS  
MAXIMIZED SOUTH OF OUR FORECAST AREA. THERE IS A STRIPE OF  
40-60% CHANCE OF 1 INCH OR MORE SOUTH OF A LINE FROM BRAINERD TO  
SANDSTONE TO HAYWARD TO PARK FALLS. THE 40% THRESHOLD FOR 0.5  
IS NOT MUCH FARTHER NORTH AND EXTENDS FROM ROUGHLY PINE RIVER TO  
MOOSE LAKE TO MELLEN TO MERCER. THE 40% CHANCE OF A TENTH OF AN  
INCH EXTENDS FROM WALKER TO TWO HARBORS TO BAYFIELD TO  
ONTONAGON, MI. THE DISTANCE OF THE 40% CHANCE OF 1 INCH OF RAIN  
AND A TENTH OF AN INCH IS ONLY ABOUT 60 MILES.  
 
RAIN TAPERS OFF SATURDAY MORNING WITH A SMALL PORTION OF  
NORTHWEST WISCONSIN SEEING A 30% CHANCE OF SHOWERS INTO THE  
EARLY AFTERNOON.  
 
AS THE HIGH AND LOW PRESSURE SYSTEMS PROPAGATE EASTWARD WINDS  
OVER WESTERN LAKE SUPERIOR WILL TURN NORTHEASTERLY AND  
STRENGTHEN FRIDAY AND REMAIN STRONG SATURDAY. THE HIGHEST WIND  
AND WAVES WILL BE IN THE SOUTHWEST ARM OF LAKE SUPERIOR WHICH  
WILL POSE A RISK OF RIP CURRENTS FOR THE BEACHES OF THE TWIN  
PORTS.  
 
SATURDAY NIGHT THROUGH NEXT THURSDAY...  
 
ANOTHER AREA OF SURFACE HIGH PRESSURE WILL PROPAGATE EASTWARD  
ACROSS THE CANADIAN PRAIRIES AND NORTHERN ONTARIO OVER THE  
WEEKEND. RAIN CHANCES SUNDAY HAVE DWINDLED AS THE NEXT AREA OF  
LOW PRESSURE TO OUR SOUTH HAS TAKEN A MORE SOUTHERLY TRAJECTORY  
THAN EARLIER FORECASTS. A FEW SPRINKLES SUNDAY AFTERNOON AND  
EVENING AREN'T OUT OF THE QUESTION.  
 
COOLER AIR, CLEAR SKIES, AND LIGHT WINDS WILL SET THE STAGE FOR  
AREAS OF FOG AND FROST SUNDAY NIGHT AND AGAIN MONDAY NIGHT.  
LOWS BOTH NIGHTS ARE FORECAST IN THE LOW 40S TO MIDDLE 30S.  
 
TEMPERATURES SUNDAY THROUGH THURSDAY WILL BE NEAR NORMAL. THEY  
WILL START OUT ON THE COOL SIDE OF THE NORMAL RANGE SUNDAY WITH  
HIGHS IN THE LOW 60S TO AROUND 70 DEGREES. TEMPS GRADUALLY WARM  
TO THE WARM SIDE OF THE NORMAL RANGE BY WEDNESDAY AND THURSDAY  
WITH HIGHS IN THE MIDDLE 60S TO LOW AND MIDDLE 70S.  
 
A CHANCE OF RAIN RETURNS WEDNESDAY NIGHT AND THURSDAY, ALTHOUGH  
OVERALL CONFIDENCE IS LOW AT THIS TIME.  
 

 
   
AVIATION /12Z TAFS THROUGH 12Z FRIDAY/
 
 
ISSUED AT 632 AM CDT THU SEP 17 2026  
 
AREAS OF FOG DEVELOPED EARLY THIS MORNING AND SHOULD MIX OUT BY  
15Z. SKIES ARE EXPECTED TO BE PARTLY CLOUDY TODAY WITH LIGHT  
WINDS. HIGH STRATUS WILL BEGIN TO MOVE INTO THE NORTHLAND FROM  
THE SOUTH TONIGHT. AS OF THIS MORNING IT SEEMS BRD, DLH, AND HYR  
WILL BE OVERCAST WHICH WILL LIMIT THEIR POTENTIAL FOR FOG  
DEVELOPMENT. HIB IS EXPECTED TO SEE FOG FRIDAY MORNING WITH IFR  
TO LIFR CONDITIONS. AFTER 12Z FRIDAY AN AREA OF RAIN WILL  
ADVANCE NORTHWARD AND MAY PRODUCE LOWER CEILINGS AND VISIBILITY  
AT BRD, DLH, AND HYR.  
 

 
   
MARINE /FOR NEARSHORE WATERS OF WESTERN LAKE SUPERIOR/
 
 
ISSUED AT 337 AM CDT THU SEP 17 2026  
 
EAST AND SOUTHEAST WINDS OF 5 TO 10 KNOTS ACROSS WESTERN LAKE  
SUPERIOR TODAY. WINDS VEER NORTHEASTERLY AND BEGIN TO STRENGTHEN  
TO 10 TO 15 KNOTS WITH GUSTS OF 15 TO 25 KNOTS TONIGHT IN  
RESPONSE TO SURFACE HIGH PRESSURE MOVING EASTWARD ACROSS  
NORTHERN ONTARIO AND DEVELOPING LOW PRESSURE NEAR NORTHEAST  
COLORADO. WIND WILL BECOME HAZARDOUS FOR SMALLER VESSELS. SMALL  
CRAFT ADVISORIES WILL EVENTUALLY BE NEEDED. THERE IS A CHANCE OF  
LIGHT RAIN MAINLY OVER THE SOUTHERN HALF OF THE WATERS FRIDAY  
AFTERNOON THROUGH FRIDAY NIGHT. WINDS WILL RELAX OVER MOST OF  
WESTERN LAKE SUPERIOR SATURDAY WITH THE EXCEPTION OF THE  
SOUTHWEST ARM AND AREAS NEAR THE OUTER APOSTLE ISLANDS DOWN TO  
SAXON HARBOR. SATURDAY NIGHT THROUGH TUESDAY WILL SEE A DIURNAL  
DECREASE IN WIND SPEEDS AND GUSTS DURING THE NIGHT THROUGH MID-  
MORNING AND THEN AN INCREASE IN WIND SPEEDS LATE MORNING THROUGH  
EARLY EVENING. ADDITIONAL SMALL CRAFT ADVISORIES MAY BE NEEDED.  
THERE IS A 20% CHANCE OF GALES TO 35 KNOTS OVER THE EASTERN  
APOSTLE ISLANDS TO SAXON HARBOR SUNDAY AFTERNOON.  
 
FOR THE OPEN WATER DISCUSSION, REFER TO THE NWS MARQUETTE AREA  
FORECAST DISCUSSION AT WEATHER.GOV/MQT.  
 

 
   
FIRE WEATHER
 
 
ISSUED AT 337 AM CDT THU SEP 17 2026  
 
NO FIRE WEATHER CONCERNS. MIN RHS THROUGH THE FORECAST PERIOD  
REMAIN ABOVE 40% WITH HIGHS IN THE 60S AND LOW 70S. RAIN CHANCES  
WILL RETURN EARLY FRIDAY MORNING AND LINGER INTO SATURDAY  
MORNING. RAIN CHANCES AND AMOUNTS HAVE BEEN TRENDING FARTHER  
SOUTH WITH TIME EACH DAY. AS OF THIS MORNING THE HEAVIEST RAIN  
STILL LOOKS TO REMAIN TO OUR SOUTH BUT WE DO HAVE A 40-60%  
CHANCE OF SEEING 1" OF RAIN FROM SOUTHERN PINE INTO PRICE  
COUNTIES. TOTALS TAPER OFF AS YOU HEAD NORTH AND THERE WILL  
LIKELY BE A SHARP GRADIENT AS DRY AIR FROM CANADA UNDERCUTS SOME  
OF THE RAIN TOTALS. AREAS NORTH OF A LINE FROM WALKER TO DULUTH  
TO MERCER ARE UNLIKELY TO SEE MEASURABLE RAIN.  
 
SEE THE FIRE WEATHER FORECAST PRODUCT FOR A MORE THOROUGH  
BREAKDOWN OF FIRE WEATHER CONDITIONS.  
 

 
   
DLH WATCHES/WARNINGS/ADVISORIES
 
 
MN...DENSE FOG ADVISORY UNTIL 10 AM CDT THIS MORNING FOR MNZ018-019-  
025-026-033>036.  
WI...NONE.  
MARINE...NONE.  
 

 
 

 
 
DISCUSSION...HUYCK  
AVIATION...HUYCK  
MARINE...HUYCK  
FIRE WEATHER...HUYCK  
 
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