913  
FXUS63 KDLH 211746  
AFDDLH  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE DULUTH MN  
1246 PM CDT MON APR 21 2025  
   
KEY MESSAGES
 
 
- ACTIVE PATTERN THROUGH THE WEEK WITH THE NEXT WAVE OF SHOWERS  
ENTERING TUESDAY MORNING. THERE WILL BE SOME STORM POTENTIAL  
TUESDAY BUT THE BETTER CHANCES WILL BE ON THURSDAY.  
 

 
   
DISCUSSION
 
 
ISSUED AT 352 AM CDT MON APR 21 2025  
 
CURRENT CONDITIONS/TODAY:  
 
THE PANHANDLE HOOK LOW IS CURRENTLY OVER CENTRAL WI THIS MORNING  
WITH ITS PRECIPITATION SHIELD IMPACTING NW WI AND INTO THE TWIN  
PORTS. SURFACE OBSERVATIONS ARE LARGELY REPORTING RAIN BUT LOOKING  
AT CORRELATION COEFFICIENT ON DUAL POL RADAR REVEALS A WINTRY MIX  
ALOFT WITH SOME BRIGHT BANDING OF WATER COATED SNOWFLAKES. GUIDANCE  
SUGGESTS THIS COOLER LAYER WILL SINK LOWER IN THE ATMOSPHERE LATER  
THIS MORNING AND IN COMBINATION WITH COOLING SURFACE TEMPERATURES  
SHOULD PRODUCE SOME ACCUMULATING SNOW ON GRASSY SURFACES. GIVEN THE  
WARMTH ALREADY IN PLACE WE HAVE LIMITED SNOW LIQUID RATIOS TO LESS  
THAN 10:1 LEADING TO A VERY SLUSHY SNOWFALL. OVERALL, THERE IS A 50-  
70% CHANCE OF SEEING AT LEAST AN INCH OF SNOW FOR THE GOGEBIC RANGE  
AND NORTHERN BAYFIELD, THE SAME CAN ALSO BE SAID FOR THE TIP OF THE  
ARROWHEAD.  
 
THE AFOREMENTIONED LOW PRESSURE SYSTEM WILL PULL NORTHEAST TOWARDS  
EASTERN LAKE SUPERIOR BY THE AFTERNOON WITH PRECIPITATION TAPERING  
OFF WEST TO EAST. ODDLY ENOUGH, ACROSS OUR WESTERN COUNTIES THERE  
WILL BE SOME CONCERN FOR NEAR-CRITICAL FIRE WEATHER CONDITIONS.  
MODEL SOUNDINGS SHOW DRY MID AND LOW LEVELS WITH MIXING HEIGHTS  
BETWEEN 5-7 KFT. THIS IS ENTIRELY INCUMBENT ON THE CLOUD DECK  
CURRENTLY IN PLACE CLEARING OUT THOUGH. IF SKIES OUT WEST CAN CLEAR  
BY 10AM THEN WE STAND A VERY GOOD CHANCE OF SEEING MIN RHS PLUMMET TO  
25% OR LOWER THIS AFTERNOON.  
 
TUESDAY:  
 
NOT A VERY LONG BREAK IN THE ACTION AS A NORTHERN PLAINS LOW BRINGS  
ANOTHER ROUND OF PRECIPITATION TO THE REGION. A BROAD AREA OF  
ISENTROPIC ASCENT WILL MOVE IN FROM THE WEST TUESDAY MORNING  
INSTIGATING SOME SHOWERS. THERMAL PROFILES A WARM ENOUGH THAT THIS  
EVENT WILL BE ALL RAIN. NOT EXPECTING SEVERE WEATHER BUT THERE IS  
SOME INSTABILITY ALOFT THAT MAY LEAD TO SOME EMBEDDED STORMS.  
COVERAGE BECOMES MORE ISOLATED AS WE HEAD INTO THE AFTERNOON BUT  
WOULDN'T DISCOUNT A COUPLE OF MORE ROBUST CELLS DEVELOPING CLOSER  
TO THE LOW AS IT OCCLUDES IN SOUTHERN MANITOBA.  
 
MIDWEEK-WEEKEND:  
 
CONFIDENCE TAKES A BIT OF A HIT AS WE MOVE INTO THE MIDWEEK  
TIME FRAME AS THE 00Z SUITE OF DETERMINISTIC GUIDANCE STRUGGLES  
WITH THE PROGRESSION OF THE CUT OFF LOW IN SOUTHERN CANADA. FOR  
NOW, WE HAVE OSCILLATED BETWEEN 0-30% POPS FOR THE WEDNESDAY  
TIME FRAME. THE FORECAST STARTS TO COME INTO BETTER AGREEMENT AS  
WE HEAD INTO THURSDAY. CLUSTER ANALYSIS OF THE MSLP SHOWS A  
TROUGH DIGGING ACROSS THE CENTRAL PLAINS WHICH WOULD PROVIDE US  
ANOTHER SURGE OF MOISTURE AND POTENTIALLY SOME INSTABILITY FOR  
THUNDERSTORMS. TIMING DIFFERENCES IN BETWEEN THE EURO AND GFS  
ARE STILL KIND OF STAGGERING WITH THE GFS ROUGHLY 12 HRS FASTER  
THAN THE EURO. AFTER THIS SYSTEM CLEARS OUT WE SHOULD HAVE A  
QUIET SATURDAY WITH HIGHS IN THE 50S AND 60S.  
 

 
   
AVIATION /18Z TAFS THROUGH 18Z TUESDAY/
 
 
ISSUED AT 1237 PM CDT MON APR 21 2025  
 
MVFR STRATUS AND RAIN/SNOW SHOWERS EXIT NORTHWEST WISCONSIN  
OVER THE NEXT FEW HOURS AS NORTHERLY WINDS GUSTING TO 18 KNOTS  
AND CLEAR SKIES BUILD OVER THE NORTHLAND THROUGH LATE THIS  
AFTERNOON. A FEW TERMINALS MAY (40-50%) CHANCE SEE LOCALIZED FOG  
DEVELOPMENT 06-12Z TONIGHT UNDER CALM WINDS. WINDS SHIFT  
SOUTHEASTERLY 09-12Z AHEAD OF THE NEXT ROUND OF RAINFALL MOVING  
SOUTHWEST TO NORTHEAST TOMORROW MORNING.  
 

 
   
MARINE /FOR NEAR SHORE WATERS OF WESTERN LAKE SUPERIOR/
 
 
ISSUED AT 352 AM CDT MON APR 21 2025  
 
A PANHANDLE HOOK LOW IS BRINGING WIDESPREAD RAIN ACROSS THE LAKE  
THIS MORNING. THE LOW IS PROJECTED TO MOVE INTO EASTERN LAKE  
SUPERIOR THIS AFTERNOON. WIND SPEEDS THIS MORNING WILL BE INCREASED  
AT THE HEAD OF THE LAKE DUE TO FUNNELING WITH SOME GUSTS OF 30 KTS  
OUT OF THE NORTHEAST POSSIBLE. THROUGH THE DAY EXPECT WINDS TO BACK  
TO OUT OF THE WEST BY THE LATE AFTERNOON WITH SPEEDS GRADUALLY  
DECREASING. SMALL CRAFT ADVISORIES ARE IN EFFECT AND WILL BEGIN TO  
EXPIRE THIS AFTERNOON AND EVENING. WAVES ALONG THE OUTER APOSTLE  
ISLANDS MAY TAKE ADDITIONAL TIME TO SUBSIDE WHICH MAY WARRANT AN  
EXTENSION DEPENDING ON TRENDS.  
 
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 4 PM CDT THIS AFTERNOON FOR LSZ121-  
146>148-150.  
SMALL CRAFT ADVISORY UNTIL 1 PM CDT THIS AFTERNOON FOR LSZ142-  
143.  
 

 
 

 
 
DISCUSSION...BRITT  
AVIATION...NLY  
MARINE...BRITT  
 
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