335
FXUS63 KDLH 082339
AFDDLH

Area Forecast Discussion
National Weather Service Duluth MN
639 PM CDT Fri Aug 8 2025

.KEY MESSAGES...

- Warm and humid this afternoon with isolated showers and
  thunderstorms.

- Severe thunderstorms are expected late this evening and
  tonight with all modes of severe weather possible.

- Drier and less humid for the weekend with periodic rain
  chances next week along with near normal temperatures.

&&

.DISCUSSION...
Issued at 347 PM CDT Fri Aug 8 2025

Low pressure was located near Winnipeg this afternoon with a
cold front trailing into northwestern Minnesota and eastern
South Dakota. A warm/stationary boundary was analyzed across
southern Minnesota. Cloud cover left from earlier convection was
prevalent across the Upper Midwest with some showers and
embedded thunderstorms trying to develop along the periphery of
this cloud cover across northeastern Minnesota. A fairly stout
cap was in place and is expected to persist this afternoon and
keep most convection at bay. With the expansive cloud cover,
temperatures have not been able to warm as previously forecast
and the warm front remains stalled out well to our south. Have
cancelled the Heat Advisory as a result.

Heading into this evening, the cold front will push eastward
into an airmass characterized by dewpoints in the upper 60s and
lower 70s and CAPE in the 2000-4000 J/kg range. Despite a
southwesterly low-level jet ahead of the front, overall shear
ahead of the front looks to remain rather anemic, only reaching
around 20 to 30 knots across the Northland. Storms are expected
to develop in the vicinity of the Red River Valley and push
eastward. With better shear to our west, there may be some
discrete storms at first, but quick upscale growth into an MCS
is expected before arriving in the Northland. All modes of
severe weather will be possible with mid-level lapse rates
around 8.5 C/km leading to a large hail threat and DCAPE in
excess of 1200 J/kg leading to a damaging wind threat. A few
tornadoes will also be possible with SRH around 150 m2/s2 and
strong turning in the low levels. There also remains a flash
flood concern with PWATs nearing 2" which is near the top of
climatology. Storms are expected to be moving at 20-30 knots,
which should limit this threat, but training along the front may
lead to isolated areas of flash flooding. Storms are most likely
to move into our western areas after 9-10PM and be largely clear
of our northwest Wisconsin zones by around 6AM. There is some
concern for a stronger corridor of wind potential across
northeastern Minnesota, but models have struggled with where
this may set up.

The front may linger across northwest Wisconsin on Saturday
keeping chances for storms in the forecast into the afternoon
hours. A few stronger storms cannot be ruled out across Ashland,
Iron Sawyer and Price counties with gusty winds and small hail
being the main threats. Otherwise, drier air will arrive behind
the front, bringing more comfortable conditions into the
region. Highs will be in the 70s and lower 80s, but with much
lower dewpoints.

Looking ahead to next week, there will be periodic chances for
showers and storms, but no strong or severe storms are currently
expected. Temperatures will remain near normal with comfortable
dewpoints.

&&

.AVIATION /00Z TAFS THROUGH 00Z SUNDAY/...
Issued at 639 PM CDT Fri Aug 8 2025

VFR conditions early this evening are expected to deteriorate
through late this evening and overnight as showers and thunderstorms
develop and move from west to east across the area. Generally
widespread MVFR conditions should develop, with localized visibility
drops due to heavy rain - but confidence is not high enough to time
those drops out just yet. Signals are on the upward trend for some
possible fog develop at HYR once thunderstorms move through.
Conditions should then improve back to VFR through Saturday morning
and afternoon.

&&

.MARINE /FOR NEAR SHORE WATERS OF WESTERN LAKE SUPERIOR/...
Issued at 347 PM CDT Fri Aug 8 2025

Primary marine concern will be a complex of showers and
thunderstorms pushing across western Lake Superior late tonight
into early Saturday morning. Wind gusts over 40 knots, hail and
heavy rainfall will all be possible with this complex. A cold
front will follow the storms with winds becoming southwesterly
for the remainder of the forecast period at 5 to 15 knots.
Stronger gusts to around 20 knots will be possible along parts
of the North Shore Sunday afternoon, however.

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...None.

&&

$$

DISCUSSION...BJH
AVIATION...Levens
MARINE...BJH