146
FXUS63 KDLH 201759
AFDDLH
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DULUTH MN
1159 AM CST MON JAN 20 2025
KEY MESSAGES
- ARCTIC COLD AND DANGEROUS WIND CHILLS WILL CONTINUE THROUGH
TUESDAY MORNING ACROSS THE NORTHLAND, AND AN EXTREME COLD
WARNING REMAINS IN EFFECT.
- LAKE EFFECT SNOW SHOWERS WILL CONTINUE THROUGH TUESDAY MORNING
ALONG THE SOUTH SHORE. ADDITIONAL ACCUMULATIONS ACROSS
NORTHERN BAYFIELD COUNTY OF 2 TO 4 WITH LOWER TOTALS IN
NORTHEAST DOUGLAS, NORTHEAST ASHLAND, AND NORTHERN IRON
COUNTIES.
DISCUSSION
ISSUED AT 437 AM CST MON JAN 20 2025
BITTERLY COLD TEMPERATURES ARE IN PLACE ACROSS THE UPPER
MIDWEST THIS MORNING. SEAGULL RAWS WINS THE GOLDEN ICICLE SO FAR
THIS MORNING WITH -41 DEGREES. A MNDOT SITE NEAR ASH LAKE IS IN
CLOSE SECOND WITH -38 DEGREES. ELY AIRPORT AND THE STREAM GAUGE
NEAR WINTON TIE FOR THIRD AT -36 DEGREES. I WOULD EXPECT SOME
OF OUR TYPICALLY COLDER COOP STATIONS WILL COME IN WITH SIMILAR
VALUES LATER THIS MORNING. WIND CHILLS HAVE BEEN AS COLD AS -49
AT GRAND MARAIS AIRPORT OVERNIGHT. WHERE THE WINDS ARE BLOWING
AT A BRISK 3 TO 6 MPH FARTHER SOUTH INTO CENTRAL MINNESOTA AND
NORTHWEST WISCONSIN, AIR TEMPERATURES ARE 20 TO 25 DEGREES
WARMER WITH VALUES IN THE -15 TO -25 DEGREE RANGE.
A SUBTLE SHORTWAVE TROUGH AND LOBE OF VORTICITY OVER SOUTHERN
MANITOBA AND THE EASTERN DAKOTAS THIS MORNING WILL CONTINUE TO
MOVE SOUTHEASTWARD TODAY. THERE MAY BE ENOUGH LIFT TO GENERATE
THICKER CLOUDS THROUGH EARLY AFTERNOON, MAINLY OVER NORTH-
CENTRAL AND CENTRAL MINNESOTA. ANOTHER SURGE OF ARCTIC AIR WILL
ACCOMPANY THE WAVE, WHICH WILL KEEP TEMPS COLDER TODAY THAN
YESTERDAY.
LAKE-EFFECT SNOW WILL PERSIST DOWNWIND OF LAKE SUPERIOR TODAY
THROUGH TUESDAY MORNING. I WOULD EXPECT TO SEE CONVECTIVE CLOUDS
DEVELOP ACROSS THE REST OF THE NORTHLAND AGAIN TODAY AS DIURNAL
HEATING OCCURS. LOOK FOR FLURRIES AWAY FROM LAKE SUPERIOR
ANYWHERE THOSE CLOUDS DEVELOP. DANGEROUS WIND CHILLS WILL
PERSIST THROUGH THE DAY CLIMBING INTO THE -20 TO -35 DEGREE
RANGE FOR A TIME THIS AFTERNOON AS TEMPERATURES WARM UP TO THE
SINGLE DIGITS AND TEENS BELOW ZERO. EXTREME COLD WARNINGS REMAIN
IN EFFECT FOR THE NORTHLAND UNTIL NOON TUESDAY. AT THAT TIME WE
MAY NEED A PERIOD OF COLD WEATHER ADVISORIES INTO WEDNESDAY
MORNING.
A SUBTLE RIDGE WILL PROPAGATE SOUTHEASTWARD THROUGH THE
NORTHWEST FLOW ON TUESDAY. WINDS WILL BACK WESTERLY AND
SOUTHWESTERLY BRINGING DRY AND WARMER CHINOOK AIR IN FROM THE
WEST. THE CHANGE IN THE FLOW ALOFT WILL GENERATE A CONVERGENCE
BAND OF SNOW OVER LAKE SUPERIOR WHICH WILL PROPAGATE
NORTHEASTWARD TUESDAY AFTERNOON AND EVENING. LIGHT SNOW MAY COME
ONSHORE AND DELIVER A DUSTING UP TO HALF AN INCH OF
ACCUMULATION FOR PORTIONS OF THE NORTH SHORE.
BY EARLY WEDNESDAY MORNING A SHORTWAVE TROUGH IS FORECAST TO
ADVANCE SOUTHEASTWARD ACROSS THE REGION. WHILE FORECAST MODELS
CONTINUE TO INDICATE AMPLE LIFT AND MOISTURE FOR A BRIEF PERIOD
OF ACCUMULATING SNOW WEDNESDAY, I REMAIN SKEPTICAL. THE MAIN
ISSUE IS THE SOURCE OF THE MOISTURE IN THE MODELS. TYPICALLY WE
WOULD WANT TO SEE A LONGER DURATION OF WESTERLY OR SOUTHWESTERLY
FLOW TO PUMP HIGHER THETA-E AIR INTO THE REGION. WITH THE VERY
DRY ARCTIC AIR IN PLACE PRESENTLY, A LACK OF AVAILABLE MOISTURE
OVER THE CENTRAL PLAINS, AND MEAGER MOISTURE TRAVELING ALONG AND
AHEAD OF THE WAVE FROM FAR NORTHWESTERN CANADA, I HAVE DOUBTS
REGARDING THE AMOUNT OF PRECIPITABLE WATER WHICH WILL ACTUALLY
ARRIVE. TO MATCH UP WITH NEIGHBORING OFFICES, I RAISED POPS A
BIT DURING THAT TIME, THOUGH THEY ARE CAPPED AT 30%. I LOWERED
QPF AMOUNTS FROM THE "GENEROUS" 0.02 TO 0.04" AND ESSENTIALLY
CUT THEM IN HALF. FORECAST SNOW RATIOS ON THE ORDER OF 20:1
STILL YIELD HALF AND INCH TO AN INCH OF ACCUMULATION.
FORECAST MODELS HAVE STRUGGLED FOR THE PAST MONTH AND HAVE
PERSISTENTLY OVER-FORECAST RETURN MOISTURE AND THEREFORE
OVERDOING THE RESULTANT QPF. WHILE THE DYNAMICS WILL BE PRESENT
FOR EFFICIENT SNOWFALL, THE BIG QUESTION REMAINS HOW MUCH
MOISTURE (PARTICULARLY AT THE LOW- LEVELS) WILL BE AVAILABLE AND
WILL IT BE SUFFICIENT TO SUPPORT MORE THAN A TRIFLING AMOUNT OF
SNOW.
ON A MORE POSITIVE NOTE, REGARDLESS OF HOW MUCH SNOW
ACCOMPANIES THE WAVE, TEMPERATURES WILL WARM TO NEAR NORMAL
WEDNESDAY. A BRIEF COOL DOWN IS FORECAST THURSDAY BEFORE NEAR-
NORMAL TEMPS RETURN FOR FRIDAY THROUGH THE WEEKEND.
AVIATION /18Z TAFS THROUGH 18Z TUESDAY/
ISSUED AT 1159 AM CST MON JAN 20 2025
VFR CONDITIONS AT MOST TERMINALS AT MID DAY, WITH NORTHWESTERLY
WINDS AT 5-15KTS. HIB WILL CONTINUE TO SEE MVFR/IFR CIGS AND
VIS DUE TO THE PRESENCE OF ICE CRYSTALS AND ANTHROPOGENIC
SOURCES. WILL CARRY MVFR CIGS INTO THE EVENING HOURS TODAY AT
HIB, BASED ON CONDITIONS THE LAST COUPLE DAYS AND A SIMILAR
PATTERN EXPECTED. OCCASIONAL LOWER CIGS TO MVFR ARE POSSIBLE AT
INL DUE TO CLOUD DEVELOPMENT OVER NEARBY LAKES THIS AFTERNOON.
PERSISTENT LOW CLOUD AND LAKE EFFECT SNOW SHOWERS WILL CONTINUE
TO IMPACT LOCATIONS ALONG THE SOUTH SHORE, BUT DO NOT ANTICIPATE
THIS ACTIVITY AFFECTING HYR.
AS A TROUGH CROSSES THE REGION TODAY AND WINDS BACK TO THE
SOUTHWEST TONIGHT AND EARLY TUESDAY. THIS WILL AID IN IMPROVING
CONDITIONS AT HIB BY TUESDAY MORNING. SOUTHWESTERLY WINDS WILL
INCREASE TO 7-10KTS THROUGH THE MORNING, WITH OCCASIONALLY
HIGHER GUSTS.
MARINE /FOR NEAR SHORE WATERS OF WESTERN LAKE SUPERIOR/
ISSUED AT 437 AM CST MON JAN 20 2025
COLD CONDITIONS WITH GUSTY NORTHWEST WINDS WILL PERSIST THROUGH
TUESDAY MORNING. WINDS WILL BACK SOUTHWESTERLY ON TUESDAY AND
WARMER AIR WILL MOVE INTO THE REGION. CONDITIONS WILL REMAIN
HAZARDOUS FOR SMALL CRAFT THROUGH TUESDAY. HEAVY FREEZING SPRAY
IS FORECAST FROM SILVER BAY TO GRAND PORTAGE TUESDAY AFTERNOON
THROUGH EARLY WEDNESDAY MORNING IN RESPONSE TO THE GUSTY WINDS
AND BUILDING WAVES. SMALL CRAFT ADVISORIES WERE EXTENDED AND NOW
ARE IN EFFECT UNTIL WEDNESDAY AFTERNOON. ON WEDNESDAY EVENING
AND THURSDAY WINDS WILL VEER WESTERLY AND WEAKEN BRINGING AN END
TO THE HAZARDOUS CONDITIONS FOR A DAY OR TWO. STRONGER WINDS ARE
FORECAST TO RETURN BY THE WEEKEND.
FOR THE OPEN WATER DISCUSSION, REFER TO THE NWS MARQUETTE AREA
FORECAST DISCUSSION AT WEATHER.GOV/MQT.
DLH WATCHES/WARNINGS/ADVISORIES
MN...EXTREME COLD WARNING UNTIL NOON CST TUESDAY FOR MNZ010>012-
018>021-025-026-033>038.
WI...EXTREME COLD WARNING UNTIL NOON CST TUESDAY FOR WIZ001>004-
006>009.
MARINE...SMALL CRAFT ADVISORY UNTIL 4 PM CST WEDNESDAY FOR LSZ140>148-
150.
HEAVY FREEZING SPRAY WARNING FROM 4 PM TUESDAY TO 4 AM CST
WEDNESDAY FOR LSZ140>142.
DISCUSSION...HUYCK
AVIATION...HA
MARINE...HUYCK
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page