860
FXUS63 KDLH 052039
AFDDLH

Area Forecast Discussion
National Weather Service Duluth MN
339 PM CDT Sun May 5 2024

.KEY MESSAGES...

- Elevated fire weather conditions Monday with breezy southeast
  winds and 30-40 percent relative humidity.

- A round of showers and thunderstorms moves northeast into the
  Northland from Monday night through Tuesday evening. Rain
  amounts of around an inch or less expected. Severe weather is
  unlikely.

- Light shower chances linger into Wednesday and Thursday. A few
  embedded thunderstorms are possible Wednesday afternoon and
  evening across far southern portions of the Northland.

&&

.DISCUSSION...
Issued at 340 PM CDT Sun May 5 2024

Rest of Today - Monday:

Mostly sunny to partly cloudy skies are occurring across the
Northland due to some fair-weather cumulus. Light winds are also
ongoing as high pressure dominates the Upper Midwest.
Temperatures are very pleasant today, topping out in the mid-60s
later this afternoon.

Winds turn calm tonight under mainly clear skies with low
temperatures in the mid-30s to mid-40s.

We see a shortwave ridge move over the Northland on Monday on
the backside of the departing high pressure to our east and
ahead of a deepening low pressure system moving into the
Northern Plains. As a result, the Northland will remain
precipitation-free until at least Monday night, but the
increasing pressure gradient will lead to gusty southeast winds.
Due to a delay in moisture advecting into the area, elevated
fire weather conditions will develop on Monday as the gusty
winds combine with minimum relative humidity values dipping into
the 30-40% range for areas away from Lake Superior. These same
areas will also see high temperatures climb into the mid-60s to
low-70s. Meanwhile, locations near Lake-Superior will be
relegated to highs in the mid-50s due to winds off of the lake.

Monday Night - Tuesday Evening:

Moisture advection (PWATs increasing to 1-1.25 inches)begins in
earnest ahead of the approaching low-pressure system/warm front
Monday evening in response to a 40-50 knot low-level jet (850
mb). Showers and thunderstorms move into the Brainerd Lakes
beginning Monday night ahead of and along the warm front, with
precipitation spreading northeast into the Northland through
much of Tuesday before ending by Tuesday night. Some instability
(SBCAPE around 100-400 J/kg) is forecast for Tuesday afternoon
into evening from the Brainerd Lakes into NW WI, which will be
the best window of time for scattered thunderstorm development.
0-6 km bulk shear vectors will be on the weaker side (15-25
knots) with marginal mid-level lapse rates but decent low-level
lapse rates. Therefore, severe weather is not anticipated, but a
few of these storms could produce small hail (pea-size) and
brief thunderstorm gusts to 30-40 mph.

Rainfall forecast for Monday night through Tuesday evening
hasn`t shifted slightly down relative to previous forecasts.
The current amounts are expected to range from one-third of an
inch to around one inch. The highest of these amounts are
expected in east-central MN to the North Shore and into NW WI.
That said, any locations that see thunderstorms move overhead
could see amounts locally exceed one inch.

Wednesday - Thursday:

The upper-level low over the Northern Plains lingers into
Wednesday before opening up into a trough as it dives southeast
into the mid-Mississippi and Ohio River Valleys on Thursday
into Thursday night. Lighter rain showers linger in the
Northland on Wednesday into Thursday, with perhaps an embedded
thunderstorm or two across far southern portions of the
Northland on Wednesday afternoon into early evening. No severe
weather is expected with these storms.

Late Friday - Next Weekend:

Another low pressure system dives southward out of Manitoba into
the western Great Lakes for Friday PM into parts of next
weekend, leading to additional rain potential during this
timeframe. Still some spread in model guidance regarding the
exact track and duration of this system for the weekend, so have
kept PoPs in the 15-30% range for now.


&&

.AVIATION /18Z TAFS THROUGH 18Z MONDAY/...
Issued at 1238 PM CDT Sun May 5 2024

VFR conditions will persist throughout the TAF period. Scattered
to pockets of broken fair weather cumulus with bases at 5-6 kft
will continue through the afternoon before dissipating early
this evening with the loss of daytime heating. Winds remain
generally less than 10 knots until Monday morning, with
southeast winds gusting to around 20 knots for many terminals
near the end of the TAF period as the pressure gradient
increases ahead of an approaching low. Winds turn stronger after
the end of the current TAF period Monday afternoon into Monday
night out of the east with precipitation chances returning as
early as Monday night in central MN.

&&

.MARINE /FOR NEAR SHORE WATERS OF WESTERN LAKE SUPERIOR/...
Issued at 340 PM CDT Sun May 5 2024

Winds remain light at or below 15 knots tonight into early
Monday morning, starting southwesterly and shifting to easterly
later tonight.

Winds strengthen out of the east to northeast on Monday as the
pressure gradient increase between high pressure departing to
our east and low pressure moving into the Northern Plains to our
west. Conditions will become hazardous to small craft on Monday
from Port Wing to the Twin Ports and north to Silver Bay. Winds
become even stronger Monday night into Tuesday, with the
hazardous conditions expected to develop for most of western
Lake Superior on Tuesday. There is also a 40-60 percent chance
for a few gale force gusts at times late Tuesday morning into
mid-Tuesday afternoon from Two Harbors to Grand Marais, as well.
Winds weaken Tuesday 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 from 7 AM Tuesday to 1 AM CDT Wednesday
     for LSZ140-147-150.
     Small Craft Advisory from 4 AM Tuesday to 1 AM CDT Wednesday
     for LSZ141-142.
     Small Craft Advisory from 3 PM Monday to 1 AM CDT Wednesday
     for LSZ143>146.
     Small Craft Advisory from 10 AM to 4 PM CDT Tuesday for LSZ148.

&&

$$

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