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000
FXUS63 KDLH 212326
AFDDLH

Area Forecast Discussion
National Weather Service Duluth MN
626 PM CDT Sun Apr 21 2024

.KEY MESSAGES...

- Dry conditions continue through today with breezy winds.
  Northwest Wisconsin and the Arrowhead could see similar dry
  conditions Monday before rain.

- A clipper system will bring light rain with possible embedded
  thunderstorms and mixed precipitation.

- A larger system will likely bring rain to the Upper Midwest
  next weekend.

&&

.DISCUSSION...
Issued at 147 PM CDT Sun Apr 21 2024

Today and Monday morning:

Sunny skies and breezy conditions are leading to near critical
fire weather conditions today. The boundary layer mixed out
earlier than expected this morning, and RHs began to decrease
quickly as temperatures rose. Model guidance is not capturing
this decrease properly, so decreased RH a few percents below
minimum model guidance to match observations. A similar scenario
is possible for the Arrowhead and portions of northwest
Wisconsin tomorrow as dry air aloft will linger and sunny skies
will last longer before clouds from tomorrow`s system moves in.

Monday afternoon and Tuesday:

An Alberta clipper will bring light rain showers to the
Northland Monday afternoon into Tuesday. High lapse rates
throughout the vertical column over central to portions of
northern Wisconsin and most unstable CAPE values 500-1000 J/kg
will lead to embedded thunderstorms in our far southern
Wisconsin counties Tuesday afternoon. Small hail and gusty winds
are possible with these storms. No severe storms expected. In
contrast, cooler temperatures in northern Minnesota and along
the shores of Lake Superior could lead to some snow mixed in
with the rain Monday night through Tuesday. In the evening, cold
air will dip south further into Wisconsin and mix chances
increase as precipitation comes to an end. Moisture is limited
with this system with only a half to three quarters of an inch
of precipitable water. Therefore, only a couple tenths of
precipitation is expected from this system, with only a trace of
snow expected along the North Shore and in northwestern
Wisconsin.

Wednesday through the weekend:

After the low moves to the east, a high pressure settles over
the Great Lakes. Relatively cool temperatures will return with
highs in the low to mid 50s across the Northland. Dry conditions
will also return, and fire weather concerns are likely,
especially on Wednesday.

A deep trough over southern California will lead to a large low
pressure system moving into the Northern Plains and Upper
Midwest Thursday evening to Friday morning. Heavier
precipitation is possible with this system, along with chances
for thunderstorms as global models are hinting at unstable
conditions during the day over the weekend. Areas that could
receive the heaviest precipitation has shifted east into
northwest Wisconsin, with a 50% chance for an inch of rain or
more in those areas. The majority of our Minnesota counties
could see a half inch of rain or more, particularly southeast of
the Iron Range. These will continue to be monitored as
uncertainty is still high on the placement of the highest
rainfall.

&&

.AVIATION /00Z TAFS THROUGH 00Z TUESDAY/...
Issued at 626 PM CDT Sun Apr 21 2024

VFR conditions through the forecast period. Satellite this evening
shows some diurnal cumulus that will quickly erode over the next few
hours. A warm front will move across the region tomorrow morning
increasing clouds. By the afternoon hours a few showers will be
possible as a cold front advances east. Thunderstorms chances are
low currently but may increase for Monday night as an upper level
low moves into the Northern Plains

&&

.MARINE...
Issued at 147 PM CDT Sun Apr 21 2024

Northwest winds will switch to southwest overnight, and wind
speeds anywhere from 10-15 kts possible over western Lake
Superior. A clipper moving through on Monday night into Tuesday
will bring light rain showers then a mix as cold air is advected
over the lake. On the back side of the system, winds will shift
to the northeast and increase Tuesday afternoon. Winds above 20
kts and gusts up to 30 kts will make conditions hazardous to
small craft before decreasing in the evening.

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...KML
AVIATION...Britt
MARINE...KML