794
FXUS63 KDLH 290527
AFDDLH

Area Forecast Discussion
National Weather Service Duluth MN
1227 AM CDT Wed May 29 2024

.KEY MESSAGES...

- Scattered rain showers and isolated thunderstorms through
  sunset tonight. Severe weather is not expected.

- Dry weather for Wednesday and Thursday.

- Frost Advisory generally north of US Highway 2 in northeast
  Minnesota tonight. Additional frost is possible Wednesday
  night into early Thursday morning, with the best chances in
  parts of the Arrowhead of Minnesota and northwest Wisconsin.

- Rain and thunderstorm chances return Thursday night into
  Friday, with a more active weather pattern continuing into
  early next week.

&&

.DISCUSSION...
Issued at 249 PM CDT Tue May 28 2024

Diurnally driven rain showers and thunderstorms will continue
through sunset tonight across northeast Minnesota and northwest
Wisconsin underneath a cold core aloft with the upper level
low. Given modest instability and weak deep layer shear, severe
weather is not expected. Overnight, with clear skies and light
winds frost will once again be a concern for northeast
Minnesota generally north of US Highway 2 with low temperatures
in the mid 30s by Wednesday morning. A Frost Advisory is in
effect for the aforementioned areas for late tonight into early
Wednesday morning. As surface high pressure departs Wednesday
night, one more night of frost will be possible (30-50% chance)
for the Arrowhead of Minnesota and across portions of northwest
Wisconsin.

For Wednesday and Thursday shortwave upper level ridging will be in
place across the region. This will lead to a break from rain showers
and thunderstorms Wednesday through Thursday afternoon. Temperatures
will also warm in return flow with departing surface high pressure
with widespread high temperatures in the 70s by Thursday away from
Lake Superior, with cooler values in the mid 50s to the lower 60s
near the Lake.

A weak cold front is forecast to propagate across the Northland
Thursday evening and night. This will mark the return to a more
active weather period for rain showers and thunderstorms that
will continue into the weekend and early next week with multiple
waves embedded in zonal flow. Regarding the potential for severe
thunderstorms as we enter June, moisture advection does increase
from the Gulf of Mexico Sunday and Monday supporting greater
buoyancy into the Upper Midwest. CSU Machine Learning Severe
Probabilities do signal a non-zero threat for severe weather
Sunday and Monday for the Northland, and will watch the trends
over the coming days. It will also be warming up this weekend
and into next week, especially away from Lake Superior, with
widespread high temperatures in the mid 70s to lower 80s,
seasonable for early June under zonal flow.

&&

.AVIATION /06Z TAFS THROUGH 06Z THURSDAY/...
Issued at 1228 AM CDT Wed May 29 2024

Calm to light and variable winds persist through the night as
high pressure moves overhead. Given mainly clear skies and light
winds, any locations that saw rain today could see some patchy
fog development tonight into the early morning. In fact, some
patchy MVFR fog has begun to develop in parts of north-central
MN already, including KHIB. Also included some overnight fog
mention at KHYR tonight. There is a 20% for patchy IFR
visibility in fog tonight at KDLH, KHIB, and KHYR, but have held
off on this lower visibility mention in the TAFs for now. Will
continue to monitor trends throughout the night and make
amendments as needed.

Outside of the fog, VFR conditions are expected through the TAF
period with clear to mostly clear skies, aside from a few
diurnal cumulus later this morning into early afternoon and some
clouds also moving into the South Shore portions of NW WI from
Lake Superior in the morning. Winds turn light out of the
southeast in NE MN and east in NW WI during the daylight hours
today.

&&

.MARINE /FOR NEAR SHORE WATERS OF WESTERN LAKE SUPERIOR/...
Issued at 249 PM CDT Tue May 28 2024

Scattered rain showers with a few embedded thunderstorms will
continue through sunset. There is a 30-40% chance for fog
formation tonight into Wednesday morning with surface high
pressure, and trends will be monitored through the evening.
Winds will be northerly tonight around 5kts, becoming generally
easterly on Wednesday around 5kts, although locally higher
around 10kts from the northeast from Two Harbors, to the Twin
Ports to Port Wing. Waves will be 1 foot or less away from
thunderstorms through Wednesday.

For the open water discussion, refer to the NWS Marquette Area
Forecast Discussion at weather.gov/mqt.

&&

.DLH WATCHES/WARNINGS/ADVISORIES...
MN...Frost Advisory until 7 AM CDT this morning for MNZ010>012-018-
     019-021-026.
WI...None.
MARINE...None.

&&

$$

DISCUSSION...PA
AVIATION...Rothstein
MARINE...PA