227
FXUS63 KDLH 170844
AFDDLH
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DULUTH MN
344 AM CDT SUN AUG 17 2025
KEY MESSAGES
- ANOTHER ROUND OF RAIN AND THUNDERSTORMS BEGINS THIS AFTERNOON
AND CONTINUES OVERNIGHT INTO MONDAY MORNING.
- HIGH PRESSURE AND DRIER CONDITIONS RETURN FROM TUESDAY INTO
THURSDAY MORNING WITH NEAR NORMAL TEMPERATURES.
DISCUSSION
ISSUED AT 344 AM CDT SUN AUG 17 2025
HIGH PRESSURE CENTERED OVER NORTHEAST ONTARIO AND A LOW PRESSURE
SHORTWAVE LIFTING THROUGH THE DAKOTAS WILL CREATE GUSTY EASTERLY
SYNOPTIC PRESSURE GRADIENT WINDS TODAY OVER THE REGION. A FEW
OF THOSE GUSTS OF 30 TO 40 MPH MAY REACH THE TWIN PORTS LATE
MORNING TO MID- EVENING TODAY. WITH THESE EAST-NORTHEAST GUSTY
WINDS TODAY, A HIGH RIP CURRENT RISK EXISTS FOR THE IMMEDIATE
LAKE SUPERIOR WATERS IN THE TWIN PORTS. A BEACH HAZARDS
STATEMENT IS IN EFFECT TODAY FOR THOSE BEACHES DUE TO A
DANGEROUS SWIMMING CONDITIONS IN THE TWIN PORTS OF CANAL PARK,
MINNESOTA POINT, AND WISCONSIN POINT. ONSHORE FLOW UNDER
SEASONABLE COOL AIRMASS AIDS IN KEEPING MAX TEMPERATURES TODAY
IN THE MID-60S TO LOW-70S, ESPECIALLY FOR NORTHEAST MINNESOTA
DOWNWIND OF LAKE SUPERIOR.
A NOTABLE DRY LAYER FROM 3000 TO 10000 FEET IS OBSERVED ON HIGH
RES FORECAST MODEL SOUNDINGS THROUGH MID-AFTERNOON TODAY NORTH
OF A STALLED STATIONARY FRONT SLOWLY LIFTING NORTHWARD INTO
CENTRAL MINNESOTA. A FEW WIDELY SCATTERED THUNDERSTORMS AND RAIN
SHOWERS CANNOT BE ENTIRELY RULED OUT IN EARLY AFTERNOON TODAY,
BUT OUTSIDE OF THE BRAINERD LAKES REGION MINIMAL RAINFALL IS
EXPECTED. AS BETTER MESOSCALE FRONTAL FORCING ENTERS NORTH-
CENTRAL MINNESOTA LATE AFTERNOON TODAY, EXPECT AN UPTICK IN
STORM CHANCES FROM WEST TO EAST THIS EVENING. ANOMALOUS
PRECIPITABLE WATER VALUES OF 1.4 TO 1.8 INCHES ARE LIKELY IN A
LIMITED-DURATION WARM SECTOR ALOFT THIS EVENING AND OVERNIGHT.
THESE CONDITIONS UNDER A DISORGANIZED AND WEAKLY SHEARED
ENVIRONMENT AND INSTABILITY PROGGED AT LESS THAN 500 J/KG KEEP
THE MAIN THUNDERSTORM HAZARDS TO HEAVY RAINFALL OF 1-2 INCHES
AND GUSTY WINDS TO 40 MPH INTO THIS EVENING AND TONIGHT. AS THE
HEAVIER RAINFALL LINGERS MONDAY MORNING IN NORTH-CENTRAL
WISCONSIN AND THE TIP OF THE ARROWHEAD, CHANCES FOR ADDITIONAL
RAINFALL DECREASE FROM WEST TO EAST ELSEWHERE MONDAY MORNING TO
MID-DAY.
EVEN AS THOSE GUSTY EASTERLY WINDS DECREASE TONIGHT FROM SOUTH
TO NORTH NEAR LAKE SUPERIOR, EXPECT LINGERING LARGE SWELL MONDAY
FROM 2 TO 4 FEET AND FUNNELED EASTERLY WINDS GUSTING 15-20 MPH.
ANOTHER DAY OF A HIGH RIP CURRENT RISK IS POSSIBLE AGAIN MONDAY
SO ANOTHER BEACH HAZARDS STATEMENT MAY AGAIN BY NEEDED FOR THE
TWIN PORTS BEACHES TOMORROW.
A VERY DRY AIRMASS SETS UP FOR MONDAY NIGHT THROUGH THURSDAY
AFTERNOON TO CREATE MOSTLY SUNNY SKIES, NEAR TO SLIGHTLY BELOW
NORMAL SEASONABLE TEMPERATURES AND DRY WEATHER.
THE NEXT CANADIAN PRAIRIES SHORTWAVE TROUGH SLIDES THROUGH THE
BORDERLANDS THURSDAY TO CREATE THE NEXT ROUND OF THUNDERSTORM
CHANCES. A DECENT MOISTURE TAP AND INSTABILITY POOL ASSOCIATED
WITH A BAND OF FRONTAL FORCING IS PROGGED WITH THIS THURSDAY
SHORTWAVE. SO GIVEN THE CURRENT SYNOPTIC PATTERN A CHANCE OF
STRONG THUNDERSTORMS WILL HAVE TO BE MONITORED FOR THURSDAY
LATE AFTERNOON TO EVENING IN THE NORTHLAND.
POST-FRONTRAL WEST TO NORTHWESTERLY FLOW ALOFT SETS UP FRIDAY
INTO NEXT WEEKEND UNDER SEASONABLE TEMPERATURES.
AVIATION /06Z TAFS THROUGH 06Z MONDAY/
ISSUED AT 1238 AM CDT SUN AUG 17 2025
A BAND OF MVFR TO IFR CEILINGS CONTINUES EARLY THIS MORNING IN
THE SOUTHERN THIRD OF THE NORTHLAND, AFFECTING BRD AND HYR TAF
SITES. EXPECT THESE CONDITIONS INTO THE SUNRISE HOURS BEFORE THE
FORECAST CALLS FOR LIFTING CEILINGS SLOWLY INTO MID-MORNING.
EASTERLY WINDS INCREASE FOR LAKE SUPERIOR SHORELINE TERMINALS
12-15Z TODAY AND GUST 20-30 KNOTS INTO THIS EVENING. AN AREA OF
UPSLOPING ONSHORE FLOW INTO SOUTHERN LAKE COUNTY IS ALREADY
BEING OBSERVED ON SATELLITE AT THIS TIME. EXPECT A PERIOD OF
LOW-MVFR STRATUS ALONG THE NORTH SHORE THIS MORNING, WHICH MAY
MOVE AS FAR SOUTH AS DLH. A PREVAILING GROUP WAS PLACED FOR
THOSE FEW HOURS OF MVFR AT DLH...THE MOST LIKELY TIME PERIOD IS
12-15Z TODAY, BUT KEPT AN HOUR ON EITHER SIDE IN THE TAF FOR
UNCERTAINTY ON ONSET/ENDING TIMES. THIS AFTERNOON, MULTIPLE
ROUNDS OF SCATTERED SHOWERS AND THUNDERSTORMS MOVE INTO NORTH-
CENTRAL MINNESOTA AND SLOWLY MOVE EASTWARD INTO THIS EVENING.
EXPECT SCATTERED SHOWERS TO BECOME MORE WIDESPREAD AND LINGERING
WITH LOWERING CONDITIONS 00-03Z THIS EVENING AND LAST INTO
MONDAY MORNING.
MARINE /FOR NEAR SHORE WATERS OF WESTERN LAKE SUPERIOR/
ISSUED AT 248 AM CDT SUN AUG 17 2025
HIGH PRESSURE OVER NORTHEAST ONTARIO AND INCOMING LOW PRESSURE
PASSING THROUGH THE NORTH DAKOTA AND MINNESOTA STATELINE REGION
LATER TODAY WILL CREATE A QUICK UPTICK IN EASTERLY WINDS THIS
MORNING. SUSTAINED WINDS OF 10 TO 20 KNOTS ARE LIKELY, WITH SOME
GUSTS TO 30 KNOTS AREAWIDE. THESE WINDS CREATE LARGE WAVE
HEIGHTS, ESPECIALLY FOR THIS TIME OF YEAR, ACROSS ALL WATERS
RANGING FROM 3 TO 6 FEET. EXPECT DANGEROUS CONDITIONS FOR SMALL
CRAFT AND VESSELS THROUGH TODAY WITH ADVISORIES IN EFFECT. THE
HIGHEST CONFIDENCE FOR A FEW HOUR PERIOD OF LATE AFTERNOON TO
EVENING EASTERLY GUSTS AROUND 35 KNOTS LIES FROM TWIN PORTS UP
THE NORTH SHORE. THIS RESULTED IN AN UPGRADE TO A GALE WARNING
FROM DULUTH UP THE SHORE TO TACONITE HARBOR FOR LATE MORNING TO
LATE EVENING TODAY. WHILE THE CURRENT ADVISORIES EXPIRE THIS
EVENING CURRENTLY, AN EXTENSION IN TIME FOR MANY SOUTHWEST ARM
AND NORTH SHORE ZONES IS LIKELY INTO MONDAY AS ELEVATED SWELL
LINGERS. THE NEXT ROUND OF THUNDERSTORMS BUILDS WEST TO EAST
THIS EVENING AND GENERAL THUNDERSTORM HAZARDS ARE LIKELY TONIGHT
INTO MONDAY MID-DAY.
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-
140-141-145>148-150.
SMALL CRAFT ADVISORY UNTIL 10 AM CDT THIS MORNING FOR
LSZ142>144.
GALE WARNING FROM 10 AM THIS MORNING TO 10 PM CDT THIS EVENING
FOR LSZ142>144.
DISCUSSION...NLY
AVIATION...NLY
MARINE...NLY
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