563
FXUS63 KDLH 170545
AFDDLH

Area Forecast Discussion
National Weather Service Duluth MN
1245 AM CDT Fri May 17 2024

.KEY MESSAGES...

- Areas of dense fog tonight last into early Friday morning as
  showers spread from west to east across the region.

- Another round of rain and thunderstorms expected Saturday, with
  marginally severe conditions possible.

- Very dry day Sunday before additional chances of rain and
  thunderstorms arrive through next week.

&&

.DISCUSSION...
Issued at 337 PM CDT Thu May 16 2024

Our areas of rain and fog will continue to steadily move off this
evening leaving a brief period of dry weather into Friday. Lingering
low level moist air could lead to some dense fog tonight, especially
in northeast Minnesota. A weak ripple in the upper level flow
arrives Friday, along with very warm temperatures. Afternoon high
temperatures in the high 60s and 70s expected, with some areas along
the southern CWA portion getting into the low 80s. This should lead
to some isolated to scattered rain showers tomorrow, mostly over
northern Minnesota, but CAMs suggest a couple afternoon storms in NW
WI are possible as well. Additionally, a lake breeze off Lake
Superior is expected to develop in the afternoon, which could be
another source of lift for a couple more rambunctious storms to fire
in the afternoon along the North and South shores. No severe weather
is expected tomorrow.

Another more robust shotwave moves over the Dakotas and into
Minnesota Saturday, with a stout small jet. Warm air and southern
flow continues, allow a narrow corridor of instability to nose into
the Northland. The best shear lags behind the front bringing up an
area of over 1000 J/kg MUCAPE, which may reduce the severe potential
- it will be a matter of precise timing as to whether or not we can
get an isolated severe storm or two. If they do line up correctly,
the primary hail would likely be hail up to a quarter size. This
front pushes northeast Saturday evening, leaving us dry for the
second half of the weekend.

Sunday should be a very dry day with humidities dropping into the 20-
30% range and continued warm temperatures in the 70s. The next wave
of precipitation should arrive with a low pressure system Monday,
but low level dry air may lead to the start time of that
precipitation becoming later, more midday Monday into the afternoon.
This disturbance arrives with some good shear and instability, and
will have to be monitored for any severe potential. Additional
chances for rain continue through next week, but exact details and
tracks remain uncertain at this time.

&&

.AVIATION /06Z TAFS THROUGH 06Z SATURDAY/...
Issued at 1236 AM CDT Fri May 17 2024

Dense fog, mainly along the South Shore and in northeast
Minnesota along and north of US Hwy 2 persists through 12-13Z
this morning. Rain showers and an isolated thunderstorm or two
move into north-central Minnesota 09-11Z this morning and spread
eastward into northwest Wisconsin and the Arrowhead 12-14Z.
Vicinity showers persist at all terminals due to the fairly high
uncertainty in timing and coverage of these showers throughout
today. An approaching impulse within a deeper low pressure
keeps chances of rain showers for northeast Minnesota again
after 03Z Saturday into the overnight hours Friday night.
Another round of Lake Superior-adjacent terminals could see fog
again after 03Z Saturday.

&&

.MARINE /FOR NEAR SHORE WATERS OF WESTERN LAKE SUPERIOR/...
Issued at 337 PM CDT Thu May 16 2024

Winds turn southwesterly this evening, as northeast winds subside.
This should allow the lake to lay down a little through Friday
morning. Moist air sticks around through Friday morning, which may
lead to dense fog becoming more widespread through overnight. A
Marine Dense Fog Advisory has been expanded to include all nearshore
zones through 10am Friday. Winds become northeast again Friday
afternoon, with a brief gusty period mid to late afternoon at the
head of the lake as ample daytime heating reinforces a lake breeze
circulation. Some thunderstorms may be possible close to shore
Friday afternoon as that lake breeze could pop up some storms along
the North and South shores. Winds stay northeasterly into Saturday
but ease slightly before becoming southwesterly through the day with
some stronger winds up to 20 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...Dense Fog Advisory until 10 AM CDT this morning for LSZ121-
     140>148-150.

&&

$$

DISCUSSION...Levens
AVIATION...NLy
MARINE...Levens