729
FXUS63 KDLH 212327
AFDDLH
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DULUTH MN
627 PM CDT MON SEP 21 2026
KEY MESSAGES
- WIDESPREAD FROST TONIGHT AWAY FROM LAKE SUPERIOR WITH SOME
LOCATIONS FALLING TO FREEZING OR JUST BELOW. ANOTHER ROUND OF
FROST EXPECTED WEDNESDAY MORNING, BUT NOT AS WIDESPREAD.
- PERSISTENT NORTHEASTERLY WINDS WILL KEEP THE THREAT FOR RIP
CURRENTS IN PLACE AT TWIN PORT BEACHES THIS AFTERNOON AND
TUESDAY AND MAY LINGER INTO MID-WEEK AS WELL.
- LOW CHANCES FOR RAINFALL THROUGH THE FORECAST PERIOD.
DISCUSSION
ISSUED AT 1246 PM CDT MON SEP 21 2026
HIGH PRESSURE WAS CENTERED JUST TO THE NORTHEAST OF LAKE
SUPERIOR EARLY THIS AFTERNOON AND EXTENDED ACROSS ALL OF THE
UPPER MIDWEST. WEAK UPPER LEVEL TROUGHING WAS IN PLACE AS WELL,
LEADING TO SOME LIGHT SHOWER ACTIVITY ACROSS SOUTHERN MINNESOTA
PER RADAR AND SURFACE OBSERVATIONS. THIS ACTIVITY IS WEAKENING
AS IT MOVES NORTH AND IS NOT EXPECTED TO AFFECT THE NORTHLAND.
CLEARING SKIES ARE EXPECTED HEADING INTO TONIGHT WITH WINDS
BECOMING LIGHT AND VARIABLE. TEMPERATURES ARE EXPECTED TO FALL
INTO THE MIDDLE TO LOWER 30S AWAY FROM LAKE SUPERIOR LEADING TO
WIDESPREAD FROST ACROSS THE REGION. SOME AREAS ALONG AND NORTH
OF THE IRON RANGE AND ACROSS THE PENOKEE RANGE MAY REACH
FREEZING OR JUST BELOW, BUT A HARD FREEZE IS NOT EXPECTED. A
FROST ADVISORY WILL BE NEEDED.
AS THE AREA OF HIGH PRESSURE MOVES TO THE EAST TOMORROW,
SOUTHERLY RETURN FLOW WILL SETUP ACROSS THE UPPER MIDWEST AND
SIGNAL THE START OF A SLOW WARMING TREND INTO THE WEEKEND. HIGHS
FOR THE REMAINDER OF THE WEEK WILL BE IN THE 60S WITH SOME UPPER
50S TUESDAY THROUGH WEDNESDAY ALONG THE NORTH SHORE WITH ONSHORE
FLOW EXPECTED. LOWS TOMORROW NIGHT WILL REMAIN ON THE COOL SIDE
IN THE MIDDLE TO UPPER 30S AND ANOTHER FROST ADVISORY MAY BE
NEEDED FOR AREAS INLAND OF LAKE SUPERIOR.
UPPER RIDGING WILL SETUP ACROSS THE CENTRAL CONUS WEDNESDAY INTO
THURSDAY WITH A SHORTWAVE PUSHING EASTWARD UNDERNEATH FOR
WEDNESDAY NIGHT INTO THURSDAY. THIS MAY LEAD TO SOME SHOWER
ACTIVITY DURING THIS TIME, BUT DRY AIR IN THE LOW LEVELS AND
HIGH PRESSURE TO THE EAST WILL WORK AGAINST THEM. ADDITIONAL
RAIN CHANCES WILL BE POSSIBLE OVER THE WEEKEND AS ANOTHER
SHORTWAVE MOVES THROUGH, BUT OVERALL CHANCES LOOK LOW. SOME 70S
WILL BE POSSIBLE BY SUNDAY AND MONDAY, MAINLY ACROSS NORTHWEST
WISCONSIN.
AVIATION /00Z TAFS THROUGH 00Z WEDNESDAY/
ISSUED AT 621 PM CDT MON SEP 21 2026
VFR CONDITIONS ARE EXPECTED FOR ALL TERMINALS FOR THE TAF PERIOD
EXCEPT FOR HIB. HIB MAY SEE FOG LATE TONIGHT, BRINGING
CONDITIONS DOWN TO IFR/LIFR FOR A FEW HOURS BEFORE SUNRISE.
WINDS WILL INCREASE OUT OF THE SOUTHEAST TOMORROW UP TO 15 KTS.
MARINE /FOR NEARSHORE WATERS OF WESTERN LAKE SUPERIOR/
ISSUED AT 1246 PM CDT MON SEP 21 2026
HIGH PRESSURE REMAINS IN PLACE OVER WESTERN LAKE SUPERIOR WITH
THE CENTER JUST TO THE EAST OF THE LAKE. THIS WILL KEEP WINDS
EASTERLY TODAY AND TOMORROW. THE STRONGEST WINDS WILL BE IN THE
WESTERN ARM AND ALONG THE SOUTH SHORE BOTH DAYS. SMALL CRAFT
ADVISORIES REMAIN IN EFFECT INTO THIS EVENING FOR THESE AREAS
WITH ANOTHER ROUND POSSIBLE TOMORROW. WINDS BECOME MORE
SOUTHEASTERLY TOMORROW NIGHT BEFORE BECOMING MORE EASTERLY ONCE
AGAIN ON WEDNESDAY. CURRENT FORECAST KEEPS GUSTS JUST BELOW
ADVISORY LEVEL, BUT IF WINDS TREND UPWARD, ANOTHER ROUND OF
ADVISORIES MAY BE NEEDED.
FOR THE OPEN WATER DISCUSSION, REFER TO THE NWS MARQUETTE AREA
FORECAST DISCUSSION AT WEATHER.GOV/MQT.
FIRE WEATHER
ISSUED AT 1246 PM CDT MON SEP 21 2026
EASTERLY WIND GUSTS OF 15 TO 20 MPH WILL BE POSSIBLE NEAR LAKE
SUPERIOR TODAY AND TOMORROW WITH LIGHTER WINDS INLAND. RH VALUES
WILL REMAIN ABOVE 45% TODAY BEFORE DRIER AIR LEADS TO VALUES
FALLING INTO THE 35 TO 45% RANGE ACROSS MUCH OF NORTHWEST
WISCONSIN FOR TOMORROW. VALES WILL REMAIN ABOVE 45% ACROSS MOST
OF NORTHEASTERN MINNESOTA TOMORROW. THERE IS A CHANCE FOR LIGHT
SHOWERS WEDNESDAY NIGHT INTO THURSDAY, MAINLY ACROSS
NORTHEASTERN MINNESOTA. A WETTING RAINFALL IS NOT EXPECTED FOR
MOST OF THE AREA WITH THIS SYSTEM.
SEE THE FIRE WEATHER FORECAST PRODUCT FOR A MORE THOROUGH
BREAKDOWN OF FIRE WEATHER CONDITIONS.
DLH WATCHES/WARNINGS/ADVISORIES
MN...FROST ADVISORY FROM MIDNIGHT TONIGHT TO 8 AM CDT TUESDAY FOR
MNZ010>012-018-019-025-026-034>038.
BEACH HAZARDS STATEMENT UNTIL 10 PM CDT THIS EVENING FOR
MNZ037.
WI...FROST ADVISORY FROM MIDNIGHT TONIGHT TO 8 AM CDT TUESDAY FOR
WIZ001>004-006>009.
BEACH HAZARDS STATEMENT UNTIL 10 PM CDT THIS EVENING FOR
WIZ001.
MARINE...SMALL CRAFT ADVISORY UNTIL 10 PM CDT THIS EVENING FOR
LSZ143>148-150.
DISCUSSION...BJH
AVIATION...KML
MARINE...BJH
FIRE WEATHER...BJH
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