Area Forecast Discussion
Issued by NWS Duluth, MN

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185
FXUS63 KDLH 120545
AFDDLH

Area Forecast Discussion
National Weather Service Duluth MN
1245 AM CDT Sun May 12 2024

.KEY MESSAGES...

- Near-critical fire weather conditions are occurring this
  afternoon. Another day of near-critical fire weather
  conditions are expected tomorrow in northeast Minnesota.

- Showers and thunderstorms are likely this evening through
  tonight as a cold front sweeps through. A storm or two in
  Koochiching County may become strong this evening, capable of
  producing wind gusts up to 50 mph.

- As the cold front moves into northwest WI, a storm or two in
  Price County may become strong to severe on Sunday afternoon.
  Gusty winds up to 60 mph and hail up to 1" in diameter are the
  main concerns.

- Dry conditions on Monday and Tuesday will give way to periodic
  chances for showers and thunderstorms mid to late this
  upcoming week into next weekend.

&&

.DISCUSSION...
Issued at 358 PM CDT Sat May 11 2024

Mostly dry conditions have been observed this afternoon as a 500mb
ridge briefly sits over the Northland. This ridging over the CWA
will be short-lived though as a shortwave trough moves into northern
Ontario tonight. A vertically-stacked low pressure associated with
this shortwave will be bringing an attendant warm and cold front
into the CWA today through tomorrow morning. As of 20z, the warm
front is approximately located along a line from northwest
Koochiching County to Hibbing. Ahead of this front, scattered
showers have developed in the Arrowhead. An appreciable amount of
dry air in the low-levels, which has led to near-critical fire
weather conditions in north-central MN today, will result in these
showers largely falling as virga this afternoon.

As the cold front approaches this evening into tonight, shower
activity will become more robust within the warm sector over north-
central MN into the Arrowhead. As the cold front propagates south
into the CWA, isolated thunderstorms will be possible (30% chance)
this evening into tonight. Instability will be marginal this evening
with MUCAPE of 200-400 J/kg . However, favorable 0-6km bulk shear of
around 30 knots could organize a few cells into strong
thunderstorms, especially in Koochiching County this evening. The
main concern with any strong storms that develop will be gusty winds
up to 50 mph and pea sized hail.

Conditions on Sunday will vary widely across the CWA as dry air
filters in behind the front in northeast Minnesota and the front
continues to propagate through northwest Wisconsin. For the MN side
of the CWA, deep mixing is expected to occur and drop minimum RH
below 25% in most locations. This will lead to near-critical fire
weather conditions and borderline Red Flag Warning criteria north of
the Iron Range, where northwest winds will be highest tomorrow. Also
happening tomorrow will be a low 30% chance of strong to severe
thunderstorms in Price County. While thunderstorm activity will
decrease tonight, additional thunderstorm development will be
possible on Sunday afternoon around Price County as diurnal heating
increases instability. Possible severe hazards include gusty winds
up to 60 mph and hail up to 1 inch in diameter.

The region will see a brief break from the active pattern early this
upcoming week as the CWA sits between low pressure systems.
Conditions will be pleasant across the area on Monday and Tuesday,
with high temps being around normal for mid May. Looking ahead, a
wet pattern is very likely (70% chance) to return to the CWA mid to
late this upcoming week. Timing discrepancies between
deterministic models are currently large, but the general
consensus is showers and thunderstorms arriving on Wednesday and
continuing into Thursday. Low pressure centers from global
ensembles reflect the high uncertainty in timing for this
midweek system, with minimal agreement in the GEFS and ECMWF
ensemble. Following this midweek system, an active pattern will
continue with additional chances for showers and storms later
this upcoming week into next weekend.

&&

.AVIATION /06Z TAFS THROUGH 06Z MONDAY/...
Issued at 1246 AM CDT Sun May 12 2024

Expect predominately VFR conditions for most terminals through
the TAF period. There is a cold front situated from northeastern
North Dakota into far northern Ontario will slide southeast
through NE MN tonight into the morning and through NW WI
later this morning into afternoon. Scattered showers and a few
embedded thunderstorms continue ahead of the front mainly over
northern and northeast Minnesota tonight. Some gusty and erratic
winds to 20 to 30 knots are possible with these showers/storms
for KINL through about 07-08Z and KHIB overnight to a lesser
extent, though conditions are expected to remain VFR with the
showers/storms due to dry air in the lower atmosphere.

Most of the remainder of the Northland stays dry with VFR
conditions today as the front tracks south. However, there is
still a 40% chance for scattered showers/storms in parts of NW
WI (including KHYR) this afternoon as the front will still be in
the vicinity at that time.

Southerly to southwesterly winds tonight (outside of
showers/storms) will quickly veer to northwesterly behind the
cold front, with gustier winds developing during the daytime
hours due to deep mixing. Much of NE MN should see gusts to 20
knots, with far northern MN seeing up to 25 knots.

&&

.MARINE /FOR NEAR SHORE WATERS OF WESTERN LAKE SUPERIOR/...
Issued at 1230 AM CDT Sun May 12 2024

Southerly winds this afternoon and evening will be relatively light,
with gusts being at or under 15 knots. Showers and isolated
thunderstorms are expected this evening into tonight. Strong to
severe thunderstorms are not expected, although cloud-to-water
lightning will be possible.

Winds turn northwesterly tomorrow, with warmer temperatures leading
to most of the stronger winds remaining over land. However, some
gusts to 20 knots are possible immediately along the North Shore
Sunday afternoon and early evening. Winds on Monday will be
relatively light across much of western Lake Superior. Increasing
northeasterly winds on Tuesday may necessitate Small Craft
Advisories as wind gusts approach 22 knots, especially around the
Twin Ports.

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...Unruh
AVIATION...Rothstein
MARINE...Unruh