856
FXUS63 KDLH 131737
AFDDLH
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DULUTH MN
1237 PM CDT MON APR 13 2026
KEY MESSAGES
- PATCHY FOG THIS MORNING
- CONDITIONAL SEVERE THREAT FOR LATE AFTERNOON AND EVENING. THE
GREATEST THREAT POTENTIAL HAS SHIFTED FURTHER SOUTH BUT OUR
SOUTHERN HALF OF THE CWA COULD STILL SEE SOME LARGE HAIL
DEVELOP BETWEEN 4PM - 1 AM.
- ACTIVE PATTERN CONTINUES WITH RAIN SHOWERS ACROSS NORTHERN MN FOR
TUESDAY AND MORE STORMS POSSIBLE IN NW WI WEDNESDAY.
- A BIGGER SYSTEM MAY BE ON THE HORIZON FOR FRIDAY WHICH WILL
ADVECT WARM AND MOIST AIR BACK INTO THE REGION SETTING THE
STAGE FOR SOME SEVERE STORMS ONCE AGAIN.
DISCUSSION
ISSUED AT 235 AM CDT MON APR 13 2026
CURRENT CONDITIONS:
WIDESPREAD STRATUS IS SINKING IN FROM THE NORTH BLANKETING THE
REGION THIS MORNING WITH SOME AREAS OF PATCHY FOG. NOTABLY IS THE
WARM TEMPERATURES WE STILL HAVE IN PLACE WITH OUR CURRENT LOWS AT
2 AM SITTING IN THE 40S AND 50S. CLOUD COVER IS LARGELY
EXPECTED TO ENDURE THROUGH THE MORNING WITH SOME SCATTERING
POSSIBLE IN THE AFTERNOON.
TODAY:
ANOTHER POTENTIALLY ACTIVE DAY WILL BE ON TAP AS ANOTHER LOW
PRESSURE INFRINGES ON THE NORTHLAND OUT OF THE CENTRAL PLAINS. A
WARM FRONT WILL SPAN WEST TO EAST AND SLOWLY MARCH NORTH INTO
OUR SOUTHERN COUNTIES IN THE AFTERNOON WITH DEWPOINTS OF 60F
KNOCKING ON OUR DOOR STEP. THIS CORRIDOR OF HIGH INSTABILITY
WILL HAVE BULK SHEAR VALUES OF 50-60 KTS TO HELP SUSTAIN
SUPERCELL DEVELOPMENT. MEAN STORM FLOW IS EXPECTED TO BE OUT OF
THE SOUTHWEST LEADING TO SOME DISCRETE CELLS INITIALLY THAT WILL
CONGEAL INTO A LINEAR MODE LATER INTO THE EVENT. HIGH RES
GUIDANCE STILL SHOWS A LOT OF VARIATION WHEN IT COMES TO THE
OVERALL COVERAGE WITH LITTLE RUN TO RUN CONSISTENCY. THE LATEST
TREND HAS LARGELY SHIFTED THE BRUNT OF THE IMPACTS FURTHER
SOUTH WITH SPC PULLING THE ENHANCED RISK OUT OF OUR CWA LEAVING
US WITH A SLIGHT RISK ACROSS OUR SOUTHERN COUNTIES. THIS WILL
ALL BE PREDICATED ON HOW THE WARM FRONT MOVES. THE MAJORITY OF
THE GUIDANCE KEEPS THE BOUNDARY ANCHORED TO OUR SOUTH WHERE THE
BETTER CHANCES FOR SEVERE WEATHER WILL BE SEEN. HOWEVER, EVEN IF
THE BOUNDARY STAYS TO OUR SOUTH WE COULD STILL SEE SOME
DEVELOPMENT ON ITS NORTHERN PERIPHERY WITH STORMS FORMING ON THE
COOL SIDE AND CLUSTERING THROUGH THE EVENING HOURS. THE
CONVECTIVE PARAMETER SPACE DOES NOT LOOK TO HAVE CHANGED TO
MUCH, WITH LHP VALUES OF 16 COMBINED WITH STEEP MID LEVEL LAPSE
RATES OF 8.5C/KM WILL BE ABLE TO GENERATE SOME LARGE HAIL AROUND
GOLF BALL SIZE. TIMING HAS SLIGHTLY SHIFTED TO LATER IN THE
AFTERNOON AND EARLY EVENING HOURS AS BOTH RIDGING ALOFT AND
CAPPING WILL WORK AGAINST CONVECTIVE INITIATION. WHILE THERE
REMAINS A LARGE SPREAD IN SOLUTIONS THE BEST TIMING LOOKS TO BE
4 PM ALONG THE BOUNDARY (WHICH MAY BE TO OUR SOUTH). THE END OF
THE THREAT PERIOD IS EXPECTED TO BE AROUND 1 AM. THE KEY TO
THIS WHOLE FORECAST WILL BE MONITORING THE WARM FRONT, THERE IS
EVEN POTENTIAL FOR STORMS TO BECOME SURFACE BASED ALONG THE
BOUNDARY WHICH COULD RESULT IN A FEW TORNADO SPIN UPS AND
DAMAGING WINDS. BUT AS OF RIGHT NOW MOST GUIDANCE KEEPS THIS
BOUNDARY TO OUR SOUTH.
TUESDAY:
MONDAY'S LOW PRESSURE SYSTEM BROADENS AND MOVES INTO CENTRAL WI. A
TRAILING INVERTED SURFACE TROUGH WILL END UP IN PHASE WITH AN UPPER
LEVEL TROUGH MOVING OUT OF THE RED RIVER VALLEY TUESDAY MORNING.
THIS COMBINATION WITH SOME ADDED DIVERGENCE ALOFT FROM AN UPPER
LEVEL JET WILL LEAD TO SOME RAIN SHOWERS CRUISING ACROSS NORTHERN
MN. THERE IS SOME WEAK INSTABILITY IN THE MORNING SO A FEW RUMBLES
OF THUNDER CAN'T FULLY BE RULED OUT, BUT THIS INSTABILITY DOES NOT
LINGER LONG AS THESE SHOWERS TRAVEL EAST THROUGH THE AFTERNOON.
OVERALL, NOT EXPECTING MUCH IN THE WAY OF IMPACTS FROM THESE
ADDITIONAL SHOWERS.
MIDWEEK INTO THE EXTENDED FORECAST:
THE ACTIVE PATTERN DOESN'T STOP ON WEDNESDAY WITH ANOTHER SYSTEM
WORKING ITS WAY ACROSS THE MIDWEST. A DEEPER TROUGH WILL DIG DOWN
INTO THE CENTRAL PLAINS AS A SURFACE LOW SLIDES ACROSS SOUTHERN MN.
THIS LOW WILL HAVE A WARM FRONT BRANCH INTO OUR REGION ONCE AGAIN
THAT WILL HELP TO INCITE SOME SHOWERS AND STORMS IN THE AFTERNOON.
EARLY LOOK AT THE PARAMETER SPACE SHOWS SOME WEAK MUCAPE TO SUPPORT
SOME ELEVATED STORM DEVELOPMENT. BULK SHEAR WILL BE AROUND 45 KTS
TO HELP SUSTAIN SOME STORM DEVELOPMENT WITH MID LEVEL LAPSE
RATES INCREASING IN THE LATE AFTERNOON AND EVENING AS THE UPPER
LEVEL TROUGH PIVOTS. SOME HAIL PRODUCTIONS CAN'T BE RULED OUT AT
THIS TIME.
BY FRIDAY WE ARE LOOKING AT A VERY ELONGATED SYSTEM MOVING ACROSS
THE PLAINS THAT WILL LIKELY DRAW IN SOME GULF MOISTURE. THE
SURGE OF SOUTHERLY WINDS WILL PUSH OUR HIGH TEMPS INTO THE 60S
AND 70S. EARLY AI NWP OUTLOOKS ARE PAINTING NW WI FOR POTENTIAL
SEVERE THUNDERSTORMS, WHICH SEEMS REASONABLE GIVEN THE TIMING OF
THE FRONTAL PASSAGE AMONG THE DETERMINISTIC GUIDANCE. ON THE
BACKSIDE OF THIS SYSTEM WE WILL SEE A REINTRODUCTION OF COLD AIR
FROM THE NW WITH OVERNIGHT LOWS DROPPING BELOW FREEZING.
LINGERING MOISTURE COULD WRAP AROUND INTO SOME SNOW SHOWERS.
GIVEN OUR WARM TEMPERATURES THROUGH THE FORECAST IT IS VERY
QUESTIONABLE WHETHER ANY OF THIS WOULD BE ABLE TO STICK. AND
EVEN IF IT DOES WE QUICKLY WARM BACK UP INTO THE 40S FOR
SATURDAY AND SOME 50S FOR SUNDAY.
AVIATION /18Z TAFS THROUGH 18Z TUESDAY/
ISSUED AT 1233 PM CDT MON APR 13 2026
MVFR TO IFR CONDITIONS CONTINUE WHERE STRATUS LINGERS THIS
AFTERNOON. SOME MAY SEE SOME LIFTING BEFORE A WARM FRONT MOVES
NORTH AND LEADS TO SCATTERED SHOWERS AND THUNDERSTORMS,
ACCOMPANIED BY MVFR/IFR CEILINGS AND VISIBILITIES.
THUNDERSTORMS ARE MOST LIKELY NEAR HYR, WITH OCCASIONAL LARGE HAIL.
ALL OTHER TERMINALS WILL LIKELY ONLY SEE RAIN SHOWERS. FOG AND
LOW STRATUS IS EXPECTED TO REDEVELOP AGAIN TONIGHT AND WILL
SLOWLY LIFT ONCE AGAIN TOMORROW MORNING.
MARINE /FOR NEARSHORE WATERS OF WESTERN LAKE SUPERIOR/
ISSUED AT 235 AM CDT MON APR 13 2026
AREAS OF DENSE FOG ACROSS THE LAKE THIS MORNING. THIS IS EXPECTED TO
PERSIST UNTIL LATE MORNING WHEN IT STARTS TO ERODE. A LOW PRESSURE
MOVING ACROSS SOUTHERN MN INTO CENTRAL WI TODAY WILL LEAD TO AN
INCREASE IN NORTHWESTERLY WINDS. SMALL CRAFT ADVISORIES HAVE BEEN
ISSUED FOR THIS EVENING AND GO INTO TUESDAY. PRIMARY CONCERNS ARE
NORTHEAST WINDS GUSTING TO 25 KTS AND BUILDING WAVES TO 4 FT.
FOR THE OPEN WATER DISCUSSION, REFER TO THE NWS MARQUETTE AREA
FORECAST DISCUSSION AT WEATHER.GOV/MQT.
FIRE WEATHER
ISSUED AT 235 AM CDT MON APR 13 2026
NO FIRE WEATHER CONCERNS AT THIS TIME. ACTIVE WEATHER PATTERN
REMAINS IN PLACE WITH MULTIPLE ROUNDS OF SHOWERS AND STORMS KEEPING
CONDITIONS MOIST THROUGH MIDWEEK.
SEE THE FIRE WEATHER FORECAST PRODUCT FOR A MORE THOROUGH
BREAKDOWN OF FIRE WEATHER CONDITIONS.
HYDROLOGY
ISSUED AT 342 AM CDT MON APR 13 2026
OVER THE PAST 72 HRS WE HAVE HAD A FEW SWATHS OF 0.25-0.50" OVER
OUR EXISTING SNOWPACK INTO THE ARROWHEAD AND THE SOUTH SHORE.
THE HIGHEST SWATCH OF OVER 1" RAN THROUGH SAWYER INTO SOUTHERN
ASHLAND AND IRON COUNTIES. THERE IS STILL SOME POTENTIAL FOR
STORMS TO DEVELOP LATE THIS AFTERNOON AND EVENING AND MOVE
ACROSS OUR FLOOD WATCH COUNTIES, BUT CHANCES HAVE DECREASED AS
THE WARM FRONT THAT WILL BE THE FOCAL POINT FOR STORM INITIATION
IS PROJECTED TO BE FARTHER SOUTH. ADDITIONAL RAINFALL OF AROUND
0.50" WILL BE POSSIBLE WITH LOCALLY HIGHER AMOUNTS SHOULD ANY
STORMS DEVELOP. TUESDAY'S ACTIVITY ALSO LOOKS TO BE MORE LIGHT
RAIN FOCUSED ON NORTHERN MN. WITH THIS IN MIND WE HAVE OPTED TO
SHORTEN THE DURATION OF THE FLOOD WATCH TO TUESDAY MORNING.
AN IMPRESSIVELY WARM DAY FOR SUNDAY HAS HELP TO MELT MORE OF THE SNOW
PACK. THE SOUTH SHORE SAW TEMPERATURES CLIMB INTO THE 60S AND 70S.
AND EVEN THE NORTH SHORE GOT IN ON SOME OF THE WARMTH ACTION WITH
HIGHS CAPPING OUT IN THE 50S. MODELED SNOW DEPTH ACROSS THE SOUTH
SHORE SAW A SIGNIFICANT DECREASE LOSING AS MUCH AS 8" IN JUST 24
HRS. THE NORTH SHORE'S >24" FOOT PRINT HAS ALSO BEEN REDUCED FROM
THE ARROWHEAD TO MAINLY THE HIGH TERRAIN OF THE NORTH SHORE. IT'S
HARD TO KNOW THE EXTENT OF HOW MUCH WATER THIS HAS RETURNED TO THE
SOIL BUT ACROSS THE SOUTH SHORE IT IS LIKELY IN EXCESS OF 2".
TAKING A TRIP THROUGH SOME OF RIVER GAUGES DOES SHOW SOME RESPONSE
TO THIS ADDED LIQUID FROM SNOW MELT. ACROSS THE MN SITES THE RIVER
HEIGHTS HAVE INCREASE 0.5-1.0' NW WI WHERE WE SAW THE MORE
IMPRESSIVE MELTING HAS SEEN RISES OF 2-3' ACROSS SEVERAL RIVERS.
THE TYLER FORKS RIVER NEAR MELLEN WI IS STILL THE PRIMARY
CONCERN WITH A FLOOD WARNING ALREADY IN EFFECT. THIS RIVER IS
EXPECTED TO CREST ON TUESDAY MORNING JUST BELOW MODERATE FLOOD
STAGE AND MOVE OUT OF MINOR FLOODING THURSDAY.
DLH WATCHES/WARNINGS/ADVISORIES
MN...NONE.
WI...FLOOD WATCH THROUGH TUESDAY MORNING FOR WIZ002>004.
MARINE...SMALL CRAFT ADVISORY FROM 9 PM THIS EVENING TO 8 AM CDT
TUESDAY FOR LSZ140-141.
SMALL CRAFT ADVISORY FROM 9 PM THIS EVENING TO 1 PM CDT
TUESDAY FOR LSZ142>147-150.
DISCUSSION...BRITT
AVIATION...KML
MARINE...BRITT
FIRE WEATHER...BRITT
HYDROLOGY...BRITT
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