045  
FXUS63 KDLH 152017  
AFDDLH  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE DULUTH MN  
317 PM CDT THU MAY 15 2025  
   
KEY MESSAGES
 
 
- A LINE OF SEVERE THUNDERSTORMS IS EXPECTED TO MOVE NORTHEAST  
ACROSS NORTHWEST WISCONSIN AND NORTHEAST MINNESOTA THIS  
AFTERNOON AND EVENING. DAMAGING WINDS, LARGE HAIL, AND  
ISOLATED TORNADOES ARE THE THREATS.  
 
- RAIN BEGINS TODAY WITH A BRIEF BREAK BEHIND TODAY'S STORMS,  
WITH WIDESPREAD LIGHTER RAIN RETURNING TONIGHT THROUGH  
SATURDAY MORNING. UP TO AN INCH AND A HALF OF RAIN POSSIBLE.  
 
- COOLER WEATHER FOR THE WEEKEND WITH SATURDAY NIGHT AND SUNDAY  
NIGHT LOWS LOWS NEAR FREEZING FOR PORTIONS OF THE REGION WITH  
FROST EXPECTED. EVEN A LITTLE SNOW WILL MIX IN FOR THE  
ARROWHEAD SATURDAY NIGHT INTO MORNING.  
 

 
   
DISCUSSION
 
 
ISSUED AT 317 PM CDT THU MAY 15 2025  
 
REST OF TODAY - THIS EVENING:  
 
DEEP LOW PRESSURE CENTERED OVER SOUTHEASTERN NORTH DAKOTA WILL  
LARGELY SPIN IN PLACE THROUGH THIS EVENING AS AN OCCLUDED FRONT  
LIFTS NORTHEAST THROUGH THE NORTHLAND. ALONG AND NORTH OF THIS  
FRONT, A NARROW WARM SECTOR HAS DEVELOPED IN CENTRAL MINNESOTA  
DOWN TO THE TWIN CITIES METRO AREA, WITH MLCAPE OF 1000-2000  
J/KG AND EFFECTIVE BULK SHEAR OF 35 TO 45 KT. THE 18Z MPX  
SOUNDING DEPICTS A FAVORABLE HODOGRAPH FOR DEVELOPMENT OF LOW-  
LEVEL ROTATION, WITH 0-1KM SRH OF 211 M^2/S^2 AND 0-3KM SRH OF  
306 M^2/S^2. SCATTERED PRE-FRONTAL DISCREET STORMS HAVE  
DEVELOPED NORTH OF THE FRONT IN CENTRAL MN WHERE THIS  
ENVIRONMENT WILL BE FAVORABLE FOR LOCALLY DAMAGING WIND GUSTS,  
LARGE HAIL (UP TO 1.5 INCHES), AND A TORNADO OR TWO THROUGH THE  
AFTERNOON.  
 
EVENTUALLY AS THE FRONT MOVES NORTHWARD, HI-RES MODEL GUIDANCE  
FAVORS STORMS IN THE TWIN CITIES METRO AREA GROWING UPSCALE INTO  
A LINE OF STORMS (QLCS) AND TRACKING NORTHEAST THROUGH THE  
NORTHLAND, FIRST IN CENTRAL AND EAST-CENTRAL MN BY LATE  
AFTERNOON AND THEN THROUGH NORTH-CENTRAL MN, NORTHWEST WI, AND  
THE ARROWHEAD THIS EVENING. AS THE AFTERNOON PROGRESSES, THE  
MLCAPE SHOULD BUILD TO 1800-2800 J/KG FROM THE BRAINERD LAKES TO  
NORTHWEST WI BY LATE AFTERNOON/EARLY EVENING WHILE SHEAR REMAINS  
STRONG, AS WELL AS 0-1KM AND 0-3KM SRH CONTINUING TO REMAIN  
FAVORABLE FOR LOW-LEVEL ROTATION AND POTENTIAL FOR A COUPLE  
TORNADOES WITH ANY MESOVORTIES THAT DEVELOP IN THE LINES OF  
STORMS THAT MOVE THROUGH. DAMAGING WIND GUSTS OF 60-70 MPH  
BECOME INCREASINGLY LIKELY WITH THE LINE OF STORMS LATER THIS  
AFTERNOON INTO EVENING IN THIS STRONGLY SHEARED AND BUOYANT  
ENVIRONMENT, PARTICULARLY IN BOWING SEGMENTS OF THE STORMS.  
LARGE HAIL UP TO HALF-DOLLAR SIZE IS ALSO POSSIBLE, PARTICULARLY  
IN NORTHWEST WI THROUGH EARLY EVENING BEFORE BETTER LAPSE RATES  
ALOFT DIMINISH. THE STEEPER LAPSE RATES IN CENTRAL/NORTHEAST MN  
TEND TO REMAIN AHEAD OF THE LINE OF STORMS, SO WHILE LARGE HAIL  
(QUARTERS) ARE STILL POSSIBLE THERE, THE THREAT IS LESSER THAN  
IN NW WI.  
 
BY MID-LATE EVENING, INSTABILITY SHOULD BEGIN TO WANE AS STORMS  
MOVE INTO THE IRON RANGE, NORTHERN MN, AND THE ARROWHEAD, SO THE  
SEVERE THREAT SHOULD GRADUALLY DROP OFF TOWARDS THE 8-10PM  
TIMEFRAME AS STORMS MOVE INTO THOSE LOCATIONS. THEREFORE, EXPECT  
THE TORNADO POTENTIAL TO DROP OFF BY THE TIME STORMS REACH THE  
IRON RANGE, WITH THE SEVERE WIND AND HAIL THREATS DROPPING OFF  
AS STORMS NEAR THE INTERNATIONAL BORDER.  
 
TONIGHT - FRIDAY NIGHT:  
 
EXPECT A LULL IN PRECIPITATION BEHIND THE LINE OF STORMS LATER  
THIS EVENING AND TONIGHT BEFORE MORE WIDESPREAD, LIGHTER  
RAINFALL OVERSPREADS THE NORTHLAND AS THE LOW-PRESSURE TREKS  
EAST ACROSS NORTHERN MN AND LAKE SUPERIOR. STEEPER LOW-LEVEL  
LAPSE RATES IN CENTRAL MN COULD EVEN BE SUFFICIENT ENOUGH TO  
PRODUCE LIMITED INSTABILITY AND A FEW THUNDERSTORMS EMBEDDED IN  
THE RAIN THERE. RAINFALL TOTALS FOR THIS AFTERNOON THROUGH  
FRIDAY NIGHT RANGE FROM AROUND 0.4" TO AROUND 1.25", WITH THE  
HIGHEST AMOUNTS (0.75-1.25") EXTENDING FROM ST. CLOUD TO THE  
BRAINERD LAKES, INTO THE TWIN PORTS AND PARTS OF THE NORTH  
SHORE UP TO SILVER BAY.  
 
THIS WEEKEND - NEXT WEEK:  
 
SPOTTIER LIGHT RAIN LINGERS ON THE BACK SIDE OF THE DEPARTING  
LOW PRESSURE FOR SATURDAY INTO SATURDAY NIGHT, WITH THE  
POTENTIAL (20-40%) FOR LIGHT SNOW TO MIX IN OVER THE ARROWHEAD  
SATURDAY NIGHT AS COLDER AIR WORKS IN, THOUGH NO SNOW IMPACTS  
ARE EXPECTED.  
 
SEASONALLY COOL TEMPERATURES, WITH HIGHS IN THE 50S TO MID 60S  
AND LOWS LARGELY IN THE 30S PERSIST SATURDAY THROUGH EARLY NEXT  
WEEK AS A PROLONGED PERIOD OF EASTERLY SURFACE WINDS PERSIST.  
THERE ARE FROST AND FREEZE CONCERNS FOR SUNDAY AND MONDAY  
MORNINGS, POSSIBLY THE ARROWHEAD TUESDAY MORNING AS TEMPERATURES  
DROP INTO THE LOW TO MID 30S.  
 
ANOTHER RAIN SYSTEM IS POSSIBLE TUESDAY - TUESDAY NIGHT, BUT THE  
TRACK OF THE LOW COULD TREND JUST SOUTH ENOUGH THAT THE  
NORTHLAND COULD MISS OUT ON MORE WIDESPREAD RAIN CHANCES. RAIN  
CHANCES RANGE FROM 30-60%, HIGHEST IN THE SOUTHERN HALF OF THE  
NORTHLAND. BEYOND EARLY NEXT WEEK, EXPECT A GRADUAL WARM UP  
AGAIN AS THE WEEK PROGRESSES.  
 

 
   
AVIATION /18Z TAFS THROUGH 18Z FRIDAY/
 
 
ISSUED AT 1255 PM CDT THU MAY 15 2025  
 
DENSE FOG NEAR DLH HAS RETREATED TO LAKE SUPERIOR AND IS NO  
LONGER IMPACTING THE TERMINAL. LOW PRESSURE TO OUR SOUTHWEST  
WILL PUSH A LINE OF STORMS THROUGH THE REGION THIS AFTERNOON AND  
EVENING, MOVING FROM SOUTHWEST TO NORTHEAST. THIS LINE WILL  
START OUT NEAR BRD AROUND 20Z AND EXIT AROUND CKC AROUND TO  
CROSS FROM SOUTHWEST TO NORTHEAST STARTING AROUND 19Z NEAR KBRD  
AND EXITING AROUND 03Z NEAR KCKC. STRONGEST STORMS SHOULD BE  
ACROSS NW WI BACK INTO CENTRAL MINNESOTA WHERE HAIL AND STRONG  
TO SEVERE WINDS COULD ACCOMPANY THE STRONGEST STORMS. LIGHTNING  
AND GUSTY WINDS WILL ACCOMPANY ALL STORMS. WINDS WILL TURN FROM  
EASTERLY TO SOUTHERLY THIS EVENING, AND REMAIN SOUTHERLY INTO  
FRIDAY.  
 

 
   
MARINE /FOR NEAR SHORE WATERS OF WESTERN LAKE SUPERIOR/
 
 
ISSUED AT 317 PM CDT THU MAY 15 2025  
 
DENSE FOG CONTINUES ON LAKE SUPERIOR INTO THIS EVENING, WITH A  
DENSE FOG ADVISORY IN EFFECT FOR THE OUTER APOSTLES AND FAR  
WESTERN LAKE SUPERIOR.  
 
A SHORT PERIOD OF GALES IS FORECAST ALONG THE NORTH SHORE  
THROUGH EARLY THIS EVENING, WITH SMALL CRAFT ADVISORIES UNTIL  
LATE EVENING AS WELL BEFORE WINDS WEAKEN ON THE LAKE. STRONG TO  
SEVERE STORMS ALSO MOVE ACROSS WESTERN LAKE SUPERIOR THIS  
EVENING, WITH LARGE HAIL AND GUSTY WINDS UP TO 40-50 KT AS THE  
MAIN THREATS. STORMS EXIT LATER THIS EVENING.  
 
WINDS REMAIN EASTERLY TO SOUTHEASTERLY INTO FRIDAY AND THEN  
GRADUALLY VEER TO NORTHWESTERLY FRIDAY NIGHT INTO SATURDAY.  
 
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...SMALL CRAFT ADVISORY UNTIL 10 PM CDT THIS EVENING FOR LSZ121-  
145>148-150.  
DENSE FOG ADVISORY UNTIL 10 PM CDT THIS EVENING FOR LSZ140>146-  
150.  
GALE WARNING UNTIL 8 PM CDT THIS EVENING FOR LSZ140>144.  
 

 
 

 
 
DISCUSSION...ROTHSTEIN  
AVIATION...ROTHSTEIN  
MARINE...ROTHSTEIN  
 
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