675  
FXUS63 KDLH 151139  
AFDDLH  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE DULUTH MN  
639 AM CDT TUE SEP 15 2026  
   
KEY MESSAGES  
 
- HAZARDOUS MARINE CONDITIONS TODAY WITH GALE FORCE WIND GUSTS  
AND HIGH WAVES ACROSS WESTERN LAKE SUPERIOR. WIND AND WAVES  
DIMINISH THIS AFTERNOON AND TONIGHT.  
 
- ADDITIONAL RAIN CHANCES LATE WEDNESDAY/WEDNESDAY NIGHT AND  
AGAIN FRIDAY INTO EARLY SATURDAY. THE LATE WEEK SYSTEM COULD  
BRING AN INCH OR MORE OF RAINFALL SOUTH OF A LINE FROM NEAR  
BRAINERD TO MOOSE LAKE TO BAYFIELD.  
 
- NEAR-NORMAL HIGH TEMPERATURES IN THE MID 60S TO LOW 70S FOR  
THE LATER HALF OF THE WEEK.  
 
 
   
UPDATE  
 
ISSUED AT 631 AM CDT TUE SEP 15 2026  
 
SHALLOW PRE-FRONTAL CONVECTION DEVELOPED SINCE 09Z OVER PORTIONS  
OF NORTHERN MINNESOTA. EXPECT THE CONVECTION TO CONTINUE TO  
EXPAND SOUTH WITH TIME IN RESPONSE TO HEIGHT FALLS AND A FEW  
HUNDRED J/KG OF MUCAPE. ADDED A 20% CHANCE OF SHOWERS WITH THAT  
LINE FOR THE NEXT FEW HOURS. REMAINDER OF FORECAST APPEARS TO BE  
ON TRACK.  
 
 
   
UPDATE  
 
ISSUED AT 257 AM CDT TUE SEP 15 2026  
 
VERTICALLY STACKED LOW PRESSURE CENTERED OVER SOUTHEAST  
MANITOBA WILL PROPAGATE RAPIDLY NORTHEAST TO JAMES BAY BY 00Z  
WEDNESDAY. LOW STRATUS AND AREAS OF DRIZZLE OVER THE NORTHLAND  
EARLY THIS MORNING ARE EXPECTED TO CLEAR AS DRIER AIR ADVANCES  
EAST IN THE STRATOSPHERIC AIR INTRUSION LOCATED OVER WESTERN  
MINNESOTA INTO SOUTHEAST NORTH DAKOTA AND EASTERN SOUTH DAKOTA  
AS OF 07Z THIS MORNING. TEMPERATURES ACTUALLY TRENDED A FEW  
DEGREES WARMER OVER THE PAST FEW HOURS IN CENTRAL AND PORTIONS  
OF NORTH-CENTRAL MINNESOTA ON THE WESTERN PERIPHERY OF THE LOW  
STRATUS. FARTHER WEST VEERING WINDS WERE FOUND AND REMAINED  
GUSTY EARLY THIS MORNING. HIGHER ALTITUDE CLOUDS CLOSER TO THE  
LOW CENTER WERE OVER MOST OF EASTERN NORTH DAKOTA AND MANITOBA.  
 
EXPECT A WEDGE OF CLEARING TO SPREAD EASTWARD ACROSS THE  
NORTHLAND THIS MORNING WHICH WILL BE FOLLOWED BY THE NOT-QUITE-  
AS-LOW STRATUS CLOSER TO THE LOW CENTER. RAISED EARLY MORNING  
LOW TEMPS A FEW DEGREES IN RESPONSE TO THIS WARMING AND THE  
PROLONGED PERSISTENCE OF THE LOW CLOUD DECK. DRIZZLE AND FOG  
WILL GRADUALLY PUSH EASTWARD AS DRIER AIR UNDERCUTS THE LOW  
STRATUS. TEMPERATURES TODAY WILL BE WARMER THAN YESTERDAY DUE IN  
LARGE PART TO THE INCREASED SUNSHINE. HIGHS WILL RANGE FROM THE  
LOW TO UPPER 60S. A FEW SPOTS IN THE ST. CROIX RIVER VALLEY MAY  
SEE LOW 70S.  
 
HIGH PRESSURE WILL DRIFT ACROSS THE REGION TONIGHT AND PROVIDE  
LIGHT WINDS AND EFFICIENT RADIATIONAL COOLING. WITH THE RECENT  
RAINFALL, TEMPS MAY NOT PLUMMET QUIET AS EFFICIENTLY AS SUNDAY  
NIGHT/EARLY MONDAY MORNING. EVEN SO, A DECISION WAS TAKEN TO  
NUDGE TEMPERATURES TONIGHT A LITTLE COLDER, BELOW THE NBM 10TH  
PERCENTILE GUIDANCE IN MANY AREAS. LOOK FOR OVERNIGHT LOWS IN  
THE MIDDLE TO UPPER 40S ALONG THE LAKE SUPERIOR SHORE IN  
NORTHWEST WISCONSIN WHILE AREAS INLAND (INCLUDING INLAND  
LOCATIONS OF THE BAYFIELD PENINSULA) WILL DROP INTO THE LOW 40S  
TO MIDDLE 30S. FROST ADVISORIES MAY BE NEEDED ONCE AGAIN TONIGHT  
SHOULD THESE TRENDS PERSIST.  
 
REMAINDER OF THE FORECAST IS ESSENTIALLY ON TRACK. DETAILS ARE  
LOCATED BELOW.  
 
 
   
DISCUSSION  
 
ISSUED AT 315 PM CDT MON SEP 14 2026  
 
WEDNESDAY - THURSDAY:  
 
A ZONAL FLOW PATTERN ALOFT SETS UP FOR WEDNESDAY AND THURSDAY.  
WEDNESDAY WILL BE DRY TO START, BUT THERE IS POTENTIAL FOR SOME  
LIGHT RAIN SHOWERS (10-40%) ACROSS FAR NORTHERN AND SOUTHERN  
PORTIONS OF THE NORTHLAND WEDNESDAY EVENING INTO EARLY WEDNESDAY  
NIGHT AS THE HIGH PRESSURE DEPARTS TO THE EAST. AN ADDITIONAL  
SURFACE HIGH PRESSURE CENTER PASSING TO OUR NORTH THURSDAY  
SHOULD KEEP THAT DAY DRY.  
 
TEMPERATURES MODERATE SLIGHTLY FOR WEDNESDAY AND THURSDAY WITH  
HIGH TEMPERATURES IN THE MID 60S TO LOW 70S ON  
WEDNESDAY/THURSDAY, AND SOME MID 70S IN THE BRAINERD LAKES TO  
NORTHWEST WISCONSIN ON THURSDAY. RELATIVELY WARMER LOWS IN THE  
40S TO LOW 50S (WARMEST NEAR LAKE SUPERIOR) WEDNESDAY AND  
THURSDAY NIGHTS SHOULD KEEP ANY ADDITIONAL FROST CHANCES AT BAY.  
 
FRIDAY - THIS WEEKEND:  
 
ANOTHER ROUND OF SHOWERS AND THUNDERSTORMS ARE FORECAST TO  
RETURN TO THE NORTHLAND ON FRIDAY THROUGH EARLY SATURDAY. LEE  
CYCLOGENESIS DEVELOPS A SURFACE LOW IN EASTERN COLORADO ON  
THURSDAY AND EJECTS IT THROUGH THE CENTRAL PLAINS THURSDAY  
NIGHT/EARLY FRIDAY AND INTO THE UPPER MISSISSIPPI RIVER VALLEY  
LATE FRIDAY INTO EARLY SATURDAY. THE EXACT TRACK OF THE SURFACE  
LOW AND THE NORTHWARD EXTENT OF ITS ATTENDANT WARM FRONT AND  
WARM SECTOR WILL DICTATE PRECIPITATION POTENTIAL, AMOUNTS, AND  
LOCATIONS IN THE NORTHLAND FOR FRIDAY THROUGH EARLY SATURDAY.  
THE ECMWF EFI QPF VALUES WITH THIS SYSTEM DO SHOW A SWATH OF  
0.5-0.6 (OUT OF A MAXIMUM OF 1) INTO PORTIONS OF INLAND  
NORTHWEST WISCONSIN ALONG WITH 90TH-PLUS PERCENTILE PWATS  
RELATIVE TO NAEFS CFSR CLIMATOLOGY, SUGGESTING POTENTIAL FOR AN  
UNUSUALLY HIGHER THAN NORMAL PRECIPITATION SIGNAL FROM SEVERAL  
EPS MEMBERS FOR THIS TIME OF YEAR. ALL THIS IS TO SAY THAT IF  
THE SURFACE WARM FRONT SETS UP IN THE IDEAL LOCATION JUST SOUTH  
OF THE AREA, A LOW-LEVEL JET RIDING OVER TO THE COOL SIDE OF THE  
FRONT COULD SET UP A BAND OF HEAVIER RAINFALL IN SOUTHERN  
PORTIONS OF THE NORTHLAND, PARTICULARLY NORTHWEST WISCONSIN. THE  
WPC DAY 5 SLIGHT RISK AREA ALSO HIGHLIGHTS THIS POTENTIAL FOR  
HEAVY RAINFALL. ADDITIONALLY, THE 13Z 9/14 RUN OF THE NBM  
RAINFALL AMOUNT PROBABILITIES FOR 0.5" OR GREATER ARE 50-75%  
SOUTH OF US-2, HIGHEST IN INLAND NW WI, BUT DON'T DROP OFF MUCH  
FOR 1" OR GREATER WITH PROBABILITIES STILL 40-65% FOR THE SAME  
AREAS.  
 
 
   
AVIATION /12Z TAFS THROUGH 12Z WEDNESDAY/  
 
ISSUED AT 631 AM CDT TUE SEP 15 2026  
 
LOW STRATUS REMAINED OVER PORTIONS OF THE EASTERN ARROWHEAD AND  
NORTHWEST WISCONSIN. EXPECT CLEARING TO MOVE INTO THOSE AREAS  
OVER THE NEXT HOUR OR TWO. STRATUS ASSOCIATED WITH THE UPPER LOW  
A LITTLE FARTHER WEST WAS MAINLY REVEALING VFR CEILINGS  
DROPPING TO MVFR OVER NORTHWEST MINNESOTA. FOLLOWING THE VFR  
TREND FOR NOW. THINK DIURNAL HEATING MAY HELP ERODE THE CLOUD  
BASES AND KEEP THEM VFR AS THEY MOVE EAST. LOW-LEVEL WIND SHEAR  
PERSIST AHEAD OF A SECONDARY COLD FRONT PUSHING EAST THROUGH  
NORTHEAST MINNESOTA AS OF 1130Z. LOOK FOR WIND SHEAR RISK TO  
DECREASE QUICKLY WITH FRONTAL PASSAGE. A FEW CONVECTIVE SHOWERS  
DEVELOPED AHEAD OF THE FRONT SINCE 09Z AND SHOULD PERSIST AND  
MOVE GENERALLY NORTHEASTWARD OVER THE NEXT SEVERAL HOURS. THERE  
IS A VERY LOW CHANCE OF LIGHTNING (AROUND 2%) WITH THOSE  
SHOWERS. HIGH PRESSURE WILL DRIFT OVER THE NORTHLAND TONIGHT  
PROVIDING CLEAR SKIES AND LIGHT WINDS. FOG AND MIST MAY DEVELOP  
EARLY TUESDAY MORNING. THERE MAY BE VERTICAL VISIBILITY IN THE  
LIFR RANGE IF FOG BECOMES THICK. THE CAVEAT TO FOG/MIST IS THE  
POTENTIAL FOR FROST TO ROB MOISTURE FROM THE AIR AND MAINTAIN  
SUFFICIENT DEWPOINT DEPRESSIONS OVERNIGHT.  
 
 
   
MARINE /FOR NEARSHORE WATERS OF WESTERN LAKE SUPERIOR/  
 
ISSUED AT 257 AM CDT TUE SEP 15 2026  
 
SURFACE LOW PRESSURE OVER SOUTHEAST MANITOBA WILL QUICKLY MOVE  
TO NEAR JAMES BAY BY THIS EVENING. WINDS WILL VEER WESTERLY AND  
PERHAPS NORTHWESTERLY AND ARE EXPECTED TO STRENGTHEN THROUGH  
LATE MORNING INTO EARLY AFTERNOON. GALES OF 35 TO 45 KTS BEGIN  
TO DEVELOP BY 12Z (7 AM CDT) AND WILL PERSIST THROUGH EARLY  
AFTERNOON. WINDS AND WAVES WILL QUICKLY DIMINISH THIS AFTERNOON  
INTO EARLY EVENING. SMALL CRAFT ADVISORIES AND GALE WARNINGS ARE  
IN EFFECT FOR MUCH OF TODAY. IT IS LIKELY THERE WILL BE A SHORT  
PERIOD OF TIME LATE TUESDAY AFTERNOON INTO EARLY EVENING WHEN  
SMALL CRAFT ADVISORIES WILL BE NEEDED AFTER THE GALE WARNINGS  
END. WINDS AND WAVES WILL BECOME LIGHT TUESDAY NIGHT AND PERSIST  
AT 15 KNOTS OR LESS FOR WEDNESDAY AND THURSDAY. ANOTHER STORM  
SYSTEM WILL MOVE THROUGH THE REGION FRIDAY AND SATURDAY WHICH  
WILL BRING ANOTHER PERIOD OF STRONGER WINDS AND HIGHER WAVES.  
 
FOR THE OPEN WATER DISCUSSION, REFER TO THE NWS MARQUETTE AREA  
FORECAST DISCUSSION AT WEATHER.GOV/MQT.  
 
 
   
FIRE WEATHER  
 
ISSUED AT 257 AM CDT TUE SEP 15 2026  
 
FIRE WEATHER CONCERNS REMAIN LOW THROUGH THE FORECAST.  
WIDESPREAD WETTING RAIN OCCURRED MONDAY. MINIMUM RELATIVE  
HUMIDITY VALUES WILL GENERALLY STAY ABOVE 45 PERCENT THE NEXT  
FEW DAYS. WEST WINDS ARE FORECAST TODAY AT 10-20 MPH WITH GUSTS  
AS HIGH AS 30 TO 40 MPH. WINDS WILL DIMINISH FOR THE REMAINDER  
OF THE WEEK. THERE WILL BE A FEW MORE CHANCES OF RAIN THIS WEEK  
WITH THE GREATEST POTENTIAL DURING THE THURSDAY NIGHT THROUGH  
SATURDAY MORNING PERIOD.  
 
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 UNTIL 4 PM CDT THIS AFTERNOON FOR LSZ121.  
SMALL CRAFT ADVISORY UNTIL 7 AM CDT THIS MORNING FOR  
LSZ140>148-150.  
GALE WARNING UNTIL 4 PM CDT THIS AFTERNOON FOR LSZ140>148-150.  
 
 
 
 
 
UPDATE...HUYCK  
DISCUSSION...ROTHSTEIN  
AVIATION...HUYCK  
MARINE...HUYCK  
FIRE WEATHER...HUYCK  
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