749
FXUS63 KDLH 142016
AFDDLH

Area Forecast Discussion
National Weather Service Duluth MN
316 PM CDT Mon Sep 14 2026

.KEY MESSAGES...

- Widespread showers with embedded thunderstorms continue
  through early tonight. Additional rainfall amounts of 0.5-1"
  expected for much of the Northland.

- Hazardous marine conditions develop late tonight into Tuesday
  with gale force wind gusts and high waves across western Lake
  Superior.

- Additional rain chances late Wednesday/Wednesday night and
  again Friday into early Saturday. The late week system could
  bring heavy rainfall (1" or more) to southern portions of the
  Northland.

- Near-normal high temperatures in the mid 60s to low 70s for
  the later half of the work week.

&&

.DISCUSSION...
Issued at 315 PM CDT Mon Sep 14 2026

Rest of Today - Tonight:

An increasingly vertically-stacked low pressure system currently
over the Dakotas will slide northeast into southern Manitoba
this evening and far northwest Ontario tonight into early
Tuesday. An attendant surface occluded front with this system
will also move west to east across the Northland this evening
and tonight. An area of strong isentropic lift ahead of the
front has led to widespread rain showers with a few embedded,
non-severe thunderstorms spreading southwest to northeast
across the Northland, arriving latest in northwest Wisconsin
mid-afternoon. Expect this area of rain to continue through
this evening into early tonight, ending from west to east as the
occluded front moves through. The isolated, embedded
thunderstorm potential persists through early/mid evening
(generally ending around 8-10 PM) as elevated instability
of 100-400 J/kg MUCAPE will be present. Despite strong bulk
shear, this limited instability combined with marginal lapse
rates aloft (6 degC/km or less) should keep most thunderstorms
that do develop as general in nature. Can`t rule out a strong
storm or two late this afternoon through early/mid-evening,
mainly in northwest Wisconsin, with hail of one-half inch or
smaller and heavy downpours leading to ponding of water on roads
and low-lying areas as the main threats. Gusty southeast
synoptic winds continue to increase through the rest of this
afternoon into evening ahead of the front, with gusts up to
around 35 mph. We will see a brief lull in winds behind the
front later this evening into early tonight before winds
increase out of the west again by late tonight/early
Tuesday morning.

Regarding precipitation, additional rainfall amounts of 0.5" to
around 1" are forecast for the remainder of this afternoon into
tonight. Highest amounts remain from central Minnesota into the
Iron Range and across far inland northwest Wisconsin. While
periodic higher rain rates are possible with any thunderstorms,
the more showery nature of these storms should preclude flash
flooding, with some patchy ponding on roadways and in low-lying
areas being the main concern. This is a welcome rainfall given
ongoing drought conditions.

Tuesday - Tuesday Night:

Even stronger winds with gusts of 30 to  strong west to
northwest winds with gusts up to 30 to 40 mph develop on Tuesday
out of the west as the surface pressure gradient remains tight
with the low pressure system moving across northwestern Ontario.
Wrap around cold air advection and lingering, shallow moisture
should keep cloud cover going across much of the Northland
Tuesday morning and in far north-central/northern Minnesota
through the afternoon and evening. We have also introduced some
sprinkle/slight chance (10-20%) rain shower mention in far
northern Minnesota on Tuesday, as well. As the low departs
farther to the northeast later in the day, winds and gusts will
be on a decreasing trend. Slightly below normal high
temperatures in the low 60s to around 70F are forecast, warmest
in northwest Wisconsin. Light winds, clearing skies, and high
pressure settling in on Tuesday night will allow low
temperatures to drop into the upper 30s to low 40s, being
slightly warmer near Lake Superior and slightly colder into the
mid 30s for typical cold spots. Patchy frost is possible in the
typical cold spots where temperatures fall into the mid 30s, but
widespread frost is unlikely (less than 30% chance of
occurrence).

Wednesday - Thursday:

A zonal flow pattern aloft sets up for Wednesday and Thursday.
Wednesday will be dry to start, but there is potential for some
light rain showers (10-40%) across far northern and southern
portions of the Northland Wednesday evening into early Wednesday
night as the high pressure departs to the east. An additional
surface high pressure center passing to our north Thursday
should keep that day dry.

Temperatures moderate slightly for Wednesday and Thursday with
high temperatures in the mid 60s to low 70s on
Wednesday/Thursday, and some mid 70s in the Brainerd Lakes to
northwest Wisconsin on Thursday. Relatively warmer lows in the
40s to low 50s (warmest near Lake Superior) Wednesday and
Thursday nights should keep any additional frost chances at bay.

Friday - This Coming Weekend:

Another round of showers and thunderstorms are forecast to
return to the Northland on Friday through early Saturday. Lee
cyclogenesis develops a surface low in eastern Colorado on
Thursday and ejects it through the Central Plains Thursday
night/early Friday and into the Upper Mississippi River Valley
late Friday into early Saturday. The exact track of the surface
low and the northward extent of its attendant warm front and
warm sector will dictate precipitation potential, amounts, and
locations in the Northland for Friday through early Saturday.
The ECMWF EFI QPF values with this system do show a swath of
0.5-0.6 (out of a maximum of 1) into portions of inland
northwest Wisconsin along with 90th-plus percentile PWATs
relative to NAEFS CFSR climatology, suggesting potential for an
unusually higher than normal precipitation signal from several
EPS members for this time of year. All this is to say that if
the surface warm front sets up in the ideal location just south
of the area, a low-level jet riding over to the cool side of the
front could set up a band of heavier rainfall in southern
portions of the Northland, particularly northwest Wisconsin. The
WPC Day 5 Slight Risk area also highlights this potential for
heavy rainfall. Additionally, the 13Z 9/14 run of the NBM
rainfall amount probabilities for 0.5" or greater are 50-75%
south of US-2, highest in inland NW WI, but don`t drop off much
for 1" or greater with probabilities still 40-65% for the same
areas.

&&

.AVIATION /18Z TAFS THROUGH 18Z TUESDAY/...
Issued at 1253 PM CDT Mon Sep 14 2026

Showers and a few embedded thunderstorms will continue spreading
northeast across the area this afternoon, then ends from west to
east this evening into early tonight. Ceilings and visibility
deteriorate with the precipitation, to mainly MVFR this
afternoon, and then IFR to IFR later this afternoon and evening
into tonight. Low-level wind shear looks to occur in two
rounds, first this afternoon into early evening with the round
of showers and storms. The second round will be behind a front
in the wake of the showers and storms tonight into early Tuesday
morning. Conditions gradually improve on Tuesday, though some
wrap around cloud cover could keep MVFR ceilings hanging around
for most terminals through much of the morning.

Wind remain strong out of the southeast today at 20-30 kts,
briefly weaken slightly tonight out of the south, and then
increase with gusts to 25-35 kts out of the west on Tuesday
morning into early afternoon.

&&

.MARINE /FOR NEARSHORE WATERS OF WESTERN LAKE SUPERIOR/...
Issued at 315 PM CDT Mon Sep 14 2026

Southeast winds increase late this afternoon and evening, with
gusts rising into the 20 to 30 knot range this evening, causing
waves to rapidly build along the North Shore. Showers with a
few thunderstorms are also expected to move across the lake the
remainder of this afternoon and evening. No strong or severe
storms are expected. After the rain moves across the area,
winds veer to southwest then west, strengthening more on Tuesday
morning into early afternoon. Gale-force winds of 35 to low-40s
kts develop by early Tuesday morning and persist through early
afternoon before rapidly decreasing in intensity later Tuesday
afternoon and evening. Small Craft Advisories go into effect
late this afternoon and persist until Gale Warnings go into
effect early Tuesday morning. It is likely there will be a short
period of time late Tuesday when Small Craft Advisories will be
needed after the Gale Warnings end. Winds and waves will
become light Tuesday night and persist at 15 knots or less for
Wednesday and Thursday.

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

&&

.FIRE WEATHER...
Issued at 315 PM CDT Mon Sep 14 2026

Fire weather concerns remain low through the forecast.
Widespread showers and some embedded, general thunderstorms
bring over half an inch to locally around 1" to the Northland
through early tonight, with rain ending from west to east later
this evening into tonight. Minimum relative humidity values
that got down to 45 percent this afternoon in northwest
Wisconsin will continue to increase as rain moves in. Southeast
winds with gusts reaching 25 to 35 mph today will shift to the
west and gust as high as 30 to around 40 mph on Tuesday behind
a departing low pressure system. Lingering cloud cover/moisture
on Tuesday should keep min RH above 45%. Winds will diminish
for the remainder of the week, with min RH on Wednesday of
40-60% (lowest in northwest Wisconsin) and 45-60% on Thursday.
Additional light shower chances are possible in far northern and
southern portions of the Northland late Wednesday and better
shower (40-80%) and thunderstorm chances on Friday into
Saturday.

See the Fire Weather Forecast product for a more thorough
breakdown of fire weather conditions.

&&

.DLH WATCHES/WARNINGS/ADVISORIES...
MN...None.
WI...None.
MARINE...Small Craft Advisory until 4 AM CDT Tuesday for LSZ121-140>148-
     150.
     Gale Warning from 4 AM to 4 PM CDT Tuesday for LSZ140>148-150.

&&

$$

DISCUSSION...Rothstein
AVIATION...Rothstein
MARINE...Rothstein
FIRE WEATHER...Rothstein