278
FXUS63 KDLH 181700
AFDDLH

Area Forecast Discussion
National Weather Service Duluth MN
1200 PM CDT Tue Aug 18 2026

.KEY MESSAGES...

- Dry weather today through Wednesday for nearly all.

- Scattered showers and non-severe storms forecast Thursday into
  Friday. A few strong thunderstorms are possible Thursday for
  the Brainerd Lakes into east-cental MN and far western WI.

- Additional chances for scattered shower and thunderstorms next
  Monday and Tuesday.

&&

.DISCUSSION...
Issued at 1155 AM CDT Tue Aug 18 2026

Dry weather will prevail for the Northland today through Wednesday
night, though a few passing showers cannot be ruled out late
this afternoon in inland north-central Wisconsin. High pressure
moving in overhead tonight helps to create ideal radiational
cooling, dropping temperatures into the low to mid-40s. Cold
spots in the Arrowhead and along the Iron Range dip into the
upper-30s tonight, but no frost is forecast.

Quiet and dry conditions continue through Wednesday with
seasonal high temperatures in the upper 70s. The next shortwave
moves through the area on Thursday and brings a 45 to 70
percent chance of showers and non-severe thunderstorms. A warm
front sets up and brings instability that is forecast to build
to around 1000 J/kg of CAPE, PWATs approaching 1.5 inches, bulk
shear of 45-50 knots and mesoscale forcing associated with the
shortwave system. A few strong thunderstorms are possible for
the Brainerd Lakes to east-central Minnesota and into far
western Wisconsin Thursday late afternoon to early evening.

A cold frontal passage on Friday keeps widely scattered post-frontal
showers in play for Friday daytime, along with non-severe
thunderstorms into the Arrowhead to the Twin Ports and across
northwest Wisconsin. Following the front, a mild and very nice
weather weekend is coming up for our region. Temperatures will
remain pleasant in the 70s with mostly sunny skies.

The next weather system after the Thursday and Friday one brings
rain shower and thunderstorm chances back to the area early Monday
morning into Tuesday. This progressive pattern will continue to
provide periodic precipitation chances.

&&

.AVIATION /18Z TAFS THROUGH 18Z WEDNESDAY/...
Issued at 1136 AM CDT Tue Aug 18 2026

VFR conditions will generally prevail for all regional TAF sites
over the next 24 hours. Northwest winds will occasionally become
gusty this afternoon around 15 to 20 knots before tapering off and
becoming light and variable tonight under clear skies. A localized
shower cannot be entirely ruled out in northwest Wisconsin this
afternoon, but terminal impacts are not anticipated.

&&

.MARINE /FOR NEARSHORE WATERS OF WESTERN LAKE SUPERIOR/...
Issued at 1137 AM CDT Tue Aug 18 2026

Southwest winds will increase this afternoon from Grand Portage to
Grand Marais, generating gusts up to 25 knots and waves of 1 to 3
feet, resulting in a Small Craft Advisory through this evening.
Winds will shift to the northwest and decrease tonight. Expect
generally light winds on Wednesday before another system brings
rain and thunderstorm chances to western Lake Superior by late
Thursday and Friday.

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

&&

.FIRE WEATHER...
Issued at 1141 AM CDT Tue Aug 18 2026

Predominantly rain-free weather is expected today and Wednesday.
Minimum relative humidity will drop to 35 to 45 percent this
afternoon with northwest winds gusting up to 18 mph. Deep mixing
on Wednesday will drop humidity values to 28 to 38 percent for
most locations, with light west to northwest winds. Showers and
storms return Thursday along a weak warm front, with another
round for Friday with a passing cold front. Light to moderate
rainfall is forecast. The best potential for a few strong
thunderstorms Thursday, along with very localized and brief
heavy rainfall, is in the Brainerd Lakes to east-central MN and
into west-central WI.

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 from 3 PM this afternoon to 7 PM CDT this
     evening for LSZ140.

&&

$$

DISCUSSION...NLy
AVIATION...NLy
MARINE...NLy
FIRE WEATHER...NLy