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000
FXUS63 KDLH 202339
AFDDLH

Area Forecast Discussion
National Weather Service Duluth MN
639 PM CDT Sat Apr 20 2024

.KEY MESSAGES...

- Near-critical fire weather concerns are occurring today and are expected
  Sunday due to low minimum relative humidity and breezy
  northwest winds.

- A clipper system will bring light rain late Monday through
  Tuesday. Some light snow could mix in Monday night into
  Tuesday.

- Additional precipitation chances late next week into weekend.

&&

.DISCUSSION...
Issued at 358 PM CDT Sat Apr 20 2024

Clouds are gradually clearing from northwest to southeast this
afternoon. All of northeast Minnesota is already cleared out,
and northwest Wisconsin should clear by late this afternoon.
Breezy northwest surface winds with gusts around 20 mph to
linger this afternoon, then diminish this evening. RH values
have dipped into the 25 to 35 percent range, and may dip a
little farther this afternoon before recovering this evening.
Even more dry weather is expected on Sunday with similarly
breezy winds but deeper mixing in the atmosphere leading to more
widespread 20 to 25 percent min RH in much of central MN into
the Iron Range, and extending into the Pine Barrens of NW WI.
Near- critical fire weather conditions look likely again on
Sunday afternoon. This will also produce a warm day with high
temperatures rising into the 50s to around 60.

A potent upper level shortwave moves through the area on Monday
through Tuesday, and should bring precipitation chances
beginning Monday afternoon, continuing through Monday night
before ending on Tuesday. Monday afternoon and evening as the
shortwave moves into the area there is some fairly strong warm
air advection going on aloft. There are some indications we may
get some convective elements with this, but the probability for
getting thunder is still relatively low- less than 20 percent,
so have left out of the forecast for now, but I suspect we may
be adding it in. Monday will also be on the warm side, with
highs pushing into the upper 50s to mid 60s for a large portion
of the area, with cooler temperatures near Lake Superior. Late
Monday night into Tuesday the cold air moves in from the
northwest, and we should get some rain/snow mixture on Tuesday.
Am not expecting much for accumulation, perhaps a sloppy dusting
on grassy or elevated surfaces. Precipitation chances dry up
for Tuesday night, and with clearing skies, I expect a chilly
night with overnight lows dropping into the 20s.

A ridge of high pressure will slide across the area on
Wednesday and Wednesday night, keeping the weather on the quiet
side with mostly sunny skies and highs in the 50s.

An upper low over the Pacific will move onto the CONUS over
southern California Wednesday, then moving across the southern
states through the rest of the work week. This system should be
able to generate our next chance of precipitation.
Unfortunately, there are some significant differences in the
operational models and there is a lot of spread in the
ensembles, depicting that there will be a trough axis moving
across the area but the details are still unclear. We currently
have some small pops beginning on Thursday continuing into
Friday and Saturday. Thursday should be near to above normal,
followed by cooler temperatures Friday and Saturday. For now, it
appears there will be enough warm air aloft to be all rain, but
would not be surprised to get some conversational snow
overnight.

&&

.AVIATION /00Z TAFS THROUGH 00Z MONDAY/...
Issued at 639 PM CDT Sat Apr 20 2024

VFR conditions are expected to prevail through the period. Gusty
west-northwest winds to around 20 to 25 knots will diminish
after sunset, but are expected to pick up again by mid to late
Sunday morning at DLH and HIB with gusts to around 20 knots.

&&

.MARINE...
Issued at 358 PM CDT Sat Apr 20 2024

Strong gusty west-southwest winds over the lake will gradually
diminish this evening. A Small Craft Advisory remains in effect
for the Apostle Islands zones. Extended this until 10 PM as
gusts are still fairly strong out at Devils Island, and expect
those to slowly diminish during the evening, which should
finally allow waves to decrease as well. Sunday and Monday
should be fairly quiet on the lake with west to southwest winds
Sunday, but then slowly picking up out of the southwest on
Monday and Monday night.


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 LSZ147-
     150.

&&

$$

DISCUSSION...LE
AVIATION...BJH
MARINE...LE