178
FXUS63 KDLH 201143
AFDDLH

Area Forecast Discussion
National Weather Service Duluth MN
643 AM CDT Sun Apr 20 2025

.KEY MESSAGES...

- Low humidity this afternoon over central to northern Minnesota
  to create elevated fire weather conditions.

- Rain develops this evening and into tonight with snow mixing
  in or becoming dominant in spots late into Monday. Chances for
  precipitation remain highest over far eastern Minnesota into
  northwest Wisconsin.

- A few more chances for mainly light rain will occur through
  the week.

&&

.DISCUSSION...
Issued at 315 AM CDT Sun Apr 20 2025

Today:

High pressure will continue to move off with south to southeast
winds occurring for most, onshore winds close to Lake Superior.
Wind gusts today from 15 to 20 mph are expected. Forecast
soundings show plenty of dry air present today which will result
in minimum humidity values this afternoon from 20 to 30 percent
across much of central to northeast Minnesota with them a bit
higher over northwest Wisconsin. Elevated fire weather
conditions are expected. Clouds will be on the increase through
the day in advance of an area of low pressure and highs will be
from 50 to 60 degrees with lakeside areas cooler.

Tonight-Monday:

Low pressure will move from the Central Plains this evening
north into southwest Wisconsin by 12Z Monday with it continuing
northeast Monday. Much of the guidance is in pretty good
agreement with the track with some small differences. PWAT
values will surge to ~0.85" over northwest Wisconsin this
evening which is in the 90th percentile. Rain will develop from
south to north this evening, first in northwest Wisconsin then
spreading north and west overnight. Chances for precipitation have
increased over eastern Minnesota as has QPF. Total QPF tonight
into Monday ranges from 1.2" over north central Wisconsin to
around a half inch from Pine County north through the North
Shore to less than a tenth of an inch in the Iron Range to the
Brainerd Lakes.

There will be some precipitation type issues that develop late
tonight into Monday morning as the boundary layer cools, with
some snow accumulation looking more likely. We have amounts of
1-3" in the snow belt of Ashland to northern Iron County to a
dusting to around 1" further west across northern Wisconsin into
the Arrowhead. We do have a bit more, closer to 2" in the tip
of the Arrowhead. Although higher amounts are not favored, there
is a 20-30% for 4"+ in the snow belt and tip of the Arrowhead.
The snow character will be wet and heavy. Some things that
could lead to more snow would be higher QPF, which the 00Z ECMWF
is indicating and boundary layer temperatures cooling faster
and more than expected. We did lower temperatures some already which
is why snow totals went up. The best period for snowfall will
be late Sunday night into midday Monday.

Precipitation chances will decrease from west to east Monday
afternoon into the evening. There will be a large temperature
gradient across the area Monday with highs around sixty from the
Brainerd Lakes north to International Falls tapering to the
upper thirties to lower forties from Park Falls/Phillips into
the Arrowhead.

Tuesday through Friday:

Several more systems will affect the Northland through the week,
each bringing chances for mainly light rain. Each will be
weaker than the system for tonight/Monday with much lower QPF.

&&

.AVIATION /12Z TAFS THROUGH 12Z MONDAY/...
Issued at 643 AM CDT Sun Apr 20 2025

VFR conditions this morning will continue as mid to high clouds
increase through the day. A low pressure system will move north
tonight and cause rain to develop over northwest Wisconsin this
evening then further west and north overnight. Ceilings will
lower to MVFR and possibly down to IFR. The rain will be most
widespread over northwest Wisconsin into far eastern Minnesota.
As boundary layer temperatures cool overnight, wet snow will mix
with the rain or switch over to all snow in spots reducing the
visibility further, possibly to IFR. The snow will be most
likely along the South Shore and North Shore late tonight into
Monday morning.

&&

.MARINE /FOR NEAR SHORE WATERS OF WESTERN LAKE SUPERIOR/...
Issued at 315 AM CDT Sun Apr 20 2025

East to northeast winds will develop today and strengthen,
especially in the Twin Ports area. Winds will increase further
tonight in response to low pressure moving north toward the
region. Winds will increase to 15 to 25 knots with gusts of 25
to 30 knots for much of the nearshore waters and Small Craft
Advisories have been issued in the Twin Ports area as early as
this afternoon with portions of the North Shore to Taconite
Harbor and all of the South Shore starting at 4AM CDT Monday.
The wind will back Monday to northerly then decrease through the
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 from 4 AM to 4 PM CDT Monday for LSZ121-
     146>148-150.
     Small Craft Advisory from 4 AM to 1 PM CDT Monday for LSZ142-
     143.
     Small Craft Advisory from 4 PM this afternoon to 10 AM CDT
     Monday for LSZ144-145.

&&

$$

DISCUSSION...Melde
AVIATION...Melde
MARINE...Melde