313
FXUS63 KDLH 161937
AFDDLH

Area Forecast Discussion
National Weather Service Duluth MN
237 PM CDT Wed Jul 16 2025

.KEY MESSAGES...

- Cooler high temperatures in the 50s and 60s today. Light rain
  showers with a few rumbles of thunder this afternoon and
  evening gradually end from west to east.

- Slightly below average temperatures in the upper 60s to 70s
  Thursday through Saturday with additional chances for showers
  and storm Friday into Saturday. Severe weather is not
  anticipated at this time.

- Temperatures in the mid 70s to low 80s are expected for
  Sunday into early next week, with another round of shower and
  storm chances early next week.

&&

.DISCUSSION...
Issued at 236 PM CDT Wed Jul 16 2025

Today - This Evening:

Two rounds of lighter rainfall are expected today through this
evening. The first round is ongoing light rain/drizzle across
east- central MN, parts of the Arrowhead, and in northwest WI.
This round is associated with low pressure over southwest
Wisconsin in response to some shortwave troughing energy at 500
mb. This initial round will slowly work east through the
remainder of the afternoon. A second 500 mb shortwave diving out
of far southern Manitoba into the Northland later this
afternoon and evening will keep clouds going across the area and
bring additional light rainfall lingering until it exits to our
east late this evening/tonight. Additional rainfall amounts
from these two rounds should be limited, ranging from 0.05-0.2
inches in northwest WI (highest in north-central WI) to a few
hundredths of an inch for east-central MN to the North Shore
and little to no additional accumulations for most of northeast
Minnesota.

Cloudy conditions, rain, and breezy northeast winds fall-like
for the remainder of today with highs in the mid 50s to 60s,
warmest in far north-central MN where clouds have had some small
breaks where sun peeks through.

Tonight - Thursday:

Clouds begin to clear out tonight, with plenty of sunshine on
Thursday alongside some isolated afternoon diurnal cumulus as
high pressure moves overhead. Can`t rule out some areas of fog
tonight into early Thursday morning given lingering low-level
moisture from rainfall the past two days. We don`t expect
widespread dense fog development, but could see some locally
dense fog in northwest WI into the Twin Ports and east-central
MN. High temperatures warm up a bit for Thursday but still on
the mild side in the upper 60s to mid 70s.

Friday - Saturday:

Additional scattered showers and thunderstorms return to
portions of the Northland early Friday morning into Saturday
morning as a couple weak shortwave troughs cross through quasi-
zonal flow at 500 mb. Thunderstorms expected to develop to our
west in the Dakotas Thursday night on the nose of the low-level
jet should be weakening as they move into the Northland Friday
morning, possibly lingering through the day on Friday. We should
then see potential for additional scattered shower and
thunderstorm development Friday PM into Friday night in the
vicinity or just north of a surface warm/stationary front. The exact
placement of this feature is still uncertain, but may favor the
best instability for storms along and south of US-2. While
0-6km bulk shear will be around 40-50 kt, MUCAPE should be
modest at around 200-700 J/kg around and south of the surface
front. Therefore, do not anticipate strong to severe
thunderstorms at this time, but that may change if future
forecasts have the surface front set up farther north in the
Northland and provide a larger warm sector/instability for
storms to work with. There is a limited potential for heavy
rainfall--a 5% WPC Excessive Rainfall Outlook, a level 1 out of
5--given forecast PWATs get to 1-1.5" with this system. Heavy
rainfall potential would be mainly tied to areas where storms
would repeatedly move over the same location, but confidence is
still low on where exactly storms set up.

Temperatures remain mild both days, with highs in the mid 60s to
low 70s on Friday and widespread 70s on Saturday.

Sunday - Early Next Week:

Surface high pressure moves back into the Northland for Sunday,
bringing drier and warmer conditions with high temperatures in
the upper 70s to low 80s. However, a more active pattern returns
to the Upper Midwest for early next week with the potential for
several rounds of showers and thunderstorms as a mid/upper-level
trough is expected to develop over the Pacific Northwest and
Canadian Rockies, kicking off a few shortwave troughs that
would lead to precipitation chances in the Upper Midwest as they
move through. Still uncertainties with the timing and placement
of the surface pattern (fronts and low pressure) early next
week, but there should be a better shear/instability combination
that what we see with the Friday system. Therefore, can`t rule
out some strong to severe storm potential early next week at
this point, with some severe guidance (e.g. the CSU Machine-
Learning Probabilities) showing at least some low-end severe
weather potential in much of the central CONUS. More humid and
warmer conditions should also return for early next week, with
more widespread highs in the 80s and dewpoints in the 60s to
around 70F.

&&

.AVIATION /12Z TAFS THROUGH 12Z THURSDAY/...
Issued at 1201 PM CDT Wed Jul 16 2025

Widespread light to locally moderate showers from east-central
Minnesota into parts of the Arrowhead and in all of northwest
Wisconsin will slowly shift east throughout the afternoon as a
low pressure system southeast of the area tracks east. There
will be an additional round of light rain moving through the
area late this afternoon and evening behind it. Expect some MVFR
visibilities at times in the rain along with IFR ceilings,
mainly at DLH and HIB. Meanwhile, near-MVFR to MVFR conditions
are in store for BRD and HIB and VFR at INL. Most terminals
return to VFR conditions by this evening, though HYR looks to
remain socked into IFR to low-end MVFR. There is some signal for
fog tonight given recent rainfall, at most terminals aside from
INL, but have only opted for MVFR visibilities for now. There is
a 20% chance for IFR visibilities in the fog tonight into early
Thursday morning.

Winds today remain gusty out of the northeast, turning light and
variable this evening into the end of the TAF period as high
pressure moves in for Thursday.

&&

.MARINE /FOR NEAR SHORE WATERS OF WESTERN LAKE SUPERIOR/...
Issued at 236 PM CDT Wed Jul 16 2025

Northeast wind gusts to around 25 knots and waves of 3 to 5 feet
persist into early this evening, particularly for the southwest
arm and western Lake Superior South Shore. Winds decrease
tonight into early Thursday and turn northerly. Winds then back
to southwesterly late Thursday morning into Friday and then
turn northeasterly late Friday into Saturday with winds in the
5 to 15 knot range with waves generally remaining around 1 foot
or less.

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 PM CDT this evening for
     MNZ037.
WI...Beach Hazards Statement until 10 PM CDT this evening for
     WIZ001.
MARINE...Small Craft Advisory until 10 PM CDT this evening for LSZ121-
     143>148-150.

&&

$$

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