122
FXUS63 KDLH 270841
AFDDLH

Area Forecast Discussion
National Weather Service Duluth MN
341 AM CDT Fri Jun 27 2025

.KEY MESSAGES...

- Clouds this morning, then some sunshine this afternoon.

- Multiple opportunities for isolated to scattered strong to
  severe thunderstorms tonight through Sunday evening.

- Warm and humid weather this weekend with highs in the 80s.

&&

.DISCUSSION...
Issued at 330 AM CDT Fri Jun 27 2025

Plenty of low clouds, areas of fog, and lingering areas of rain
(mainly up in the Arrowhead) this morning. All of this is
associated with a departing low, which will continue east today.
Clouds will probably be slow to clear out, sticking around in
most places through the morning, but eventually some sunshine is
expected this afternoon. We should see temperatures warm up
nicely into the 70s today for most places, except 60s lingering
in north-central Wisconsin as clouds will be slow to move out
there.

Storm chances tonight into Saturday morning:

Broad ridging today into tonight will develop with plenty of
southwesterly warm air and moisture advection. Strong to severe
thunderstorms may develop over North Dakota late this afternoon
and evening, eventually spreading east and making it into
north-central Minnesota later tonight. There is still plenty of
uncertainty on how these storms will initially evolve, owing to
an elevated mixed layer that will cap the environment. But,
there should be plenty of instability and shear available for
storms to blow up once the cap is busted. What that means for
us, then, is that it`s not entirely clear how strong and
organized the storms will be once they arrive here late
tonight. The most likely scenario is that they will weaken and
become non-severe for the most part, but still a stray strong to
severe storm can`t be ruled out that could produce some
localized large hail or gusty winds (~5% chance) through early
Saturday morning. We`ll continue to keep an eye on it though, as
we should have plenty of warm and moist air advection in our
region that could be enough fuel to keep storms a bit stronger
as they move in than models currently suggest.

Saturday afternoon and night storms:

More storms may develop Saturday afternoon into Saturday night.
How exactly these develop will be partially due to how storms
during the morning evolve and fall apart, as lingering
boundaries may act as a catalyst for convection in the absence
of a broader synoptic boundary. It looks like we`ll have no
shortage of instability developing (still looking like areas of
2-3+ kJ/kg MUCAPE and ~40 kt bulk shear). Busting the cap will
be key, but once it does, hodograph profiles generally look like
they could be favorable for some initial discrete supercells
(thus large hail around 1.5" or so and wind gusts 60-70 mph or
so may be possible). A tornado or two can`t be ruled out either,
and this is all looking like generally a late afternoon and
evening threat with chances lingering into the overnight as we
continue to have warm air and moisture advection. A
strengthening low-level jet could keep storms going, with
perhaps a more organized line developing (though at this time,
it looks like this may take a dive south and perhaps leave most
areas pretty quiet Saturday night). Expect changes in this
forecast as subtle changes to any of the convective ingredients
could change the outcome of how storms evolve. Right now, SPC
has outlined a slight risk (2/5) for severe storms from the
Brainerd Lakes to Hinckley areas and a marginal risk (1/5)
elsewhere, and this seems appropriate for the time being, though
there could certainly be some slight changes to this.

Sunday storms:

We will eventually have a cold front pass through late Saturday
night, and along and ahead of this on Sunday, we may have some
more isolated to scattered strong to severe thunderstorms
develop. The biggest threat for this will be over northwest
Wisconsin since that`s where the warm/moist air will be
lingering ahead of the front. MUCAPE is moderately favorable
(~1-2 kJ/kg MUCAPE), but shear (~25-35 kt) is low-end favorable
for severe weather. We could get some quick hailstorms (~1"
diameter) and strong winds (~60 mph) as storms could merge into
a line with quasi-perpendicular shear vectors to the incoming
cold front. At this point, I`d say confidence is medium-high in
Sunday`s forecast of isolated strong to severe storms, with the
best chances around Price County out ahead of the front Sunday
afternoon.

Weekend heat:

It`s still looking like it will be rather hot and muggy this
weekend, though at this point, it is not looking like it will be
anything too anomalous. We should see highs in the 80s both days
(some places high 80s), and some muggy dew points in the 60s to
around 70. With all the storms and clouds around, it doesn`t
look like this heat will need to warrant any heat advisories,
but it`ll still feel rather uncomfortable out there, especially
if you don`t have air conditioning or other ways to keep cool.
All said, a fairly typical summertime warm spell around the
Northland.

Next week:

A passing trough is expected to produce showers and
thunderstorms on Monday. Coverage of these may be somewhere
between scattered and widespread with plenty of synoptic forcing
and of course the diurnal convective component. This looks like
a low CAPE and low shear environment, so severe weather is not
expected, but it will probably be a day of some sunshine and
dodging passing showers and storms. Highs cool a bit from the
weekend, but should still be in the 70s to around 80.

Tuesday and Wednesday, it`s looking like we`ll be under the
influence of west/northwest flow, sitting between cooler air up
north and ridging redeveloping to our west. There could be some
weak upper-level waves passing through that could introduce some
rain/storm chances, perhaps later Wednesday into Thursday,
though that remains pretty uncertain. We`ll probably see some
periods of quiet weather and sunshine with occasional rain
chances.

Later in the week, it looks like the broad ridging may inch its
way east a bit, but it looks like there could very well be some
embedded upper level waves that could bring more rain/storm
chances.

&&

.AVIATION /06Z TAFS THROUGH 06Z SATURDAY/...
Issued at 1225 AM CDT Fri Jun 27 2025

Light rain showers will eventually exit to the northeast over
the next several hours into the early morning, with areas of
MVFR to IFR fog mixed in with the rain. Then, expect ceilings to
lower to LIFR to IFR for most terminals into the early morning
hours in low stratus and fog aside from INL/far north-central
Minnesota. HYR and possibly DLH could even touch VLIFR ceilings
at times with IFR fog. Otherwise, visibilities in areas of fog
will be more MVFR elsewhere. Gradually see visibilities and
ceilings improve towards mid to late morning, with VFR
conditions returning for most terminals by mid to late
afternoon. INL is expected to remain VFR throughout the TAF
period.

&&

.MARINE /FOR NEAR SHORE WATERS OF WESTERN LAKE SUPERIOR/...
Issued at 330 AM CDT Fri Jun 27 2025

Breezy conditions this morning will cause wave heights up to 3
to 5 ft and wind gusts to 25 kt, which will be hazardous for
small craft for all nearshore zones. Winds and waves are
expected to steadily decrease this morning though, and by noon,
wave heights should drop to around 3 ft or less except maybe
some 4 footers lingering for another hour or so in the Outer
Apostle Islands. Small Craft Advisories remain in effect through
this morning. Northeast winds are expected to briefly become
more northerly early this afternoon, then become more variable
in direction late this afternoon and into tonight. Winds may
become northeasterly again Saturday, but speeds are expected to
remain below 10 kt. Showers and thunderstorms are possible on
Saturday (40-50% chance), and some strong to severe storms
capable of producing large hail and temporary gusty and erratic
winds greater than 30 kt.

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

&&

.DLH WATCHES/WARNINGS/ADVISORIES...
MN...Beach Hazards Statement until 10 AM CDT this morning for
     MNZ037.
WI...Beach Hazards Statement until 10 AM CDT this morning for
     WIZ001.
MARINE...Small Craft Advisory until 10 AM CDT this morning for
     LSZ140>148.
     Small Craft Advisory until noon CDT today for LSZ150.

&&

$$

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