468
FXUS63 KDLH 262056
AFDDLH

Area Forecast Discussion
National Weather Service Duluth MN
356 PM CDT Sat Apr 26 2025

.KEY MESSAGES...

- Rain chances return to the Northland late tonight, in the
  first of several waves of showers and storms.

- A lull in shower activity is possible Sunday afternoon and
  early evening, before additional rain and thunderstorms move
  through the area Monday. The best chance for strong to severe
  storms will be Monday afternoon and evening. Additionally,
  heavy rainfall is likely.

- Cooler temperatures expected Tuesday before warming back up
  for the remainder of the week with more rain chances Wednesday
  night into Thursday.

&&

.DISCUSSION...
Issued at 229 PM CDT Sat Apr 26 2025

Surface high pressure is centered over western Lake Superior
this afternoon, with light south to southeasterly winds for much
of the Northland. Under mostly clear skies, temperatures have
warmed into the upper 40s to lower 60s. Further west, near
Brainerd Lakes and points northward, winds are increasing with a
few gusts of 15mph ahead of the next weather system. The surface
high will continue to pull east of the area tonight, with
southerly winds continuing to increase and advect moisture back
to the area. Conditions will remain rainfree this evening with
increasing clouds. Overnight lows fall into the lower 40s for
eastern portions of the Arrowhead, and mid 40s to lower 50s
elsewhere.

A large weather system will begin approaching the area tonight,
bringing several waves of showers and storms to the Northland
through Monday night. As an upper low moves northeastward from
southern California tonight, an initial shortwave will round a
flattening upper level ridge currently extending northward from
the Gulf through the Plains. Elevated forcing and increasing
moisture will allow for showers to spread southwest to northeast
beginning late tonight across the Northland. Will not rule out
a rumble of thunder, with increasing lapse rates and LLJ of
30-40kt, but with little height changes and a lack of
instability, expect this round to lean toward light to moderate
rain showers due to isentropic lift over an approaching warm
front.

A lull in activity is possible tomorrow afternoon, with mild
temperatures and breezy southerly winds. Brief height rises are
expected over the Northland as the upper trough and surface low
move into the Central Plains. A warm/stationary front will
likely extend northeastward through the area, and remain a focus
for scattered showers Sunday evening. Will bring low pops back
into the area after 7PM Sunday. A few elevated storms are
possible after midnight through Monday morning as upper and mid
level jets increase as a stronger shortwave pivots around the
base of the upper level trough over the Plains.

Expect more significant height falls by Monday afternoon, as the
surface low approaches the Northland. A warm sector will surge
northward, enhanced by increased jet features and characterized
by CAPE values over 1000J/kg and bulk shear values over 50kts.
Severe storm potential will increase, with damaging winds and
hail possible. Heavy rainfall is expected to the north of the
surface low track, where PW values of 1.0-1.2 inches are
expected. This will help suppress the surface based warm sector,
and potential for a few tornadoes, to northwest WI. We need to
consider a few limiting factors for Monday afternoon. One, how
quickly the morning activity moves out of the area, and whether
the airmass can recover or remain fairly stable. This would
result in less thunder chances and mainly heavy rainfall for
the area. Two, with strong warm advection, at least a weak cap
is expected to persist into the afternoon. This could limit
severe potential for any thunderstorms until the late
afternoon/early evening.

A cold front sweeps through the area Monday night, bringing an
end of the rain and a brief cooldown Tuesday. A few snow showers
are possible on the backside of the system early Tuesday, but do
not expect and snow accumulations. Temperatures warm back into
the 50s and 60s for the remainder of the week with another
chance for rainfall Wednesday night into Thursday.



&&

.AVIATION /18Z TAFS THROUGH 18Z SUNDAY/...
Issued at 1222 PM CDT Sat Apr 26 2025

VFR conditions continue through the overnight period, with high
pressure slowly exiting to the east. High and mid level clouds
increase this afternoon and evening, from west to east. Rain
chances increase after 12Z Sunday morning, especially near BRD
eastward to HYR. Cigs lower to MVFR for most terminals Sunday
morning as well, as winds increase from the southeast with gusts
of 20-22kts.

&&

.MARINE /FOR NEAR SHORE WATERS OF WESTERN LAKE SUPERIOR/...
Issued at 229 PM CDT Sat Apr 26 2025

Wind turn northeasterly tonight as surface high pressure exits
to the east, at 5 to 15 knots, highest in the western arm.
Winds then increase tomorrow from the southeast with gusts to
20 knots that linger into Sunday night. Rain and storm chances
arrive on Sunday and continue into Monday and Monday night.
Strong to severe storms will be possible Monday afternoon and
evening with large hail and wind gusts to 50 knots possible.

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...HA
AVIATION...HA
MARINE...HA