Duluth, Minnesota 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

794
FXUS63 KDLH 242351
AFDDLH

Area Forecast Discussion
National Weather Service Duluth MN
651 PM CDT Sun May 24 2026

.KEY MESSAGES...

- Warming trend takes off today with Tuesday expected to be the
  hottest day of the work week. Highs will be in the 80s with a
  few 90s possible.

- Off and on chances for showers and storms for the next several
  days. There is a marginal risk (threat level 1 out of 5) for
  tomorrow afternoon and evening across the Arrowhead and the
  North Shore.

&&

.DISCUSSION...
Issued at 153 PM CDT Sun May 24 2026

Current Conditions/Today:

Quite the summer time set up we are getting into for the Northland.
This morning we had some weak clusters of storms moving across
northern MN on the edge of a weak 925mb low level jet. These storms
have lost a lot of strength as we`ve moved into the mid day point
but their lingering outflow boundaries and interactions from other
lake boundaries will have a lasting effect this afternoon. The
overall scheme for today boasts an impressive warming trend with
southerly winds streaming back into the Northland. Not a strong
moisture feed at the moment but PWATs climb to 0.50-0.75" which is
enough to kick off some showers and storms at times. Instability
climbs to around 500 J/Kg MLCAPE in the afternoon with bulk shear on
the order of 30 kts. We are lacking synoptic forcing as subsidence
over the region remains abundant. Despite this, diurnally processes
intermingling with remnant boundaries stand the chance of allowing a
few storms to develop this afternoon. Mid level lapse rates remain
steep so a few stronger storms can`t be ruled out. Primary threat
would be hail the size of pennies to nickels. Additionally, today
marks the start of a warming trend with highs today in the 70s
and low 80s with cooler temps by Lake Superior.

Tonight:

Another nocturnal low level jet ramps up across the Midwest with the
nose of the jet nudging its way into our southern tier of counties.
MUCAPE will be around 500 J/kg with the better instability south of
our area. Bulk shear also remains on the fringe of ideal speeds
clocking in around 30 kts. We will have a shortwave projected to
move in from the Northern Plains that could provide a boost to
synoptic forcing helping storms to grow stronger. At this time
though the better dynamics remain to our south where SPC has a
marginal risk outlined for primarily a hail threat with damaging
winds as a secondary threat. A few of the latest high res runs are
highlighting a few cells making it as far north as the Twin Ports,
but they don`t look to have quite the juice necessary to warrant an
expansion of the severe weather outlook.

Monday:

Monday morning may see some isolated showers across NW WI as the
nocturnal jet settles down. The day will once again see a noticeable
increase in temperatures as southwest flow increases and high
temperatures climb into the 80s. We will also see a deeper pool
of moisture moving back into the region as dewpoints start to
climb into the upper 50s and 60s. This added fuel will boost our
MLCAPE to over 1000 J/kg by the afternoon hours. A cold front
is also expected to drop southeast out of Ontario in the
afternoon and evening hours providing a boost to lift that may
overcome any capping that will be in play from the warming
temperatures. Mid level lapse rates remain steep with large hail
being the primary threat and damaging wind being a secondary
threat. Timing will largely depend on the frontal boundary but
early estimates would light up northern MN after 3PM with the
window for severe closing after 10PM. To account for this, SPC
has introduced a marginal risk for the Arrowhead and into the
South Shore.

Tuesday:

Not much relief in the wake of the cold front as it stalls out
Monday night and we reverse the tides with a warm front advancing
back north. Tuesday in particular looks to be our hottest day with
highs in the upper 80s and some low 90s on tap. Decent southerly
flow will also prevent the Lake breeze from penetrating too far
inland. This warm moist environment will sport some very impressive
CAPE values in excess of 2500 J/kg and mid level lapse rates remain
favorable for rapid ascent. There may also be some ridge runners
able to boost some synoptic forcing as a 500mb ridge sees a few
impulses rotate through. Placement of the frontal boundary and
the runners remain in high variance between the 12Z suite of
deterministic guidance. Additionally, the best bulk shear may
be displaced to the north of the better instability corridor.
For now, we do not have a severe weather outlook and are
carrying 20-40% for showers and storms in the afternoon and
evening.

Mid week - End of the work week:

On Wednesday the surface boundary looks to retreat to the edges of
our CWA as the upper level ridge sinks into the Midwest. In the
absence of strong southerly flow Lake Superior should be able to
flex its muscles and spread cooler temperatures across most of the
region via its lake breeze. Depending on how far this stable air
manages to permeate across the region we may have some very limited
coverage for showers and storms to develop in the afternoon and
evening.

Surface high pressure continues to linger across the Great Lakes
region for Thursday and the early parts of Friday leading to a
similar set up as Wednesday. Return flow from the exiting high
pressure doesn`t look to impact the region until late Friday. At
which point we may see a return of showers and thunderstorms pending
on the placement of the high pressure.

&&

.AVIATION /00Z TAFS THROUGH 00Z TUESDAY/...
Issued at 650 PM CDT Sun May 24 2026

VFR conditions largely prevail across much of northeast
Minnesota and northwest Wisconsin through Monday morning. The
exception is some scattered shower/storm activity and outflow
near HYR through 01-02Z this evening that could produce brief
MVFR visibilities in rain. Have also included a wind shift with
the thunderstorm outflow/lake breeze combination. Tonight, a low
level jet could (20-30% chance) develop some isolated to
scattered thunderstorms from east-central Minnesota into inland
northwest Wisconsin, which could impact HYR. Latest
deterministic model runs have been shunting this activity
slightly farther south, so HYR could be missed entirely. On
Monday afternoon, a low pressure system sliding through
northwest Ontario will bring a cold front into far northern
Minnesota and the Minnesota Arrowhead, with scattered shower and
thunderstorm activity developing along it and moving southeast
into Monday evening. INL and HIB could be impacted by this
precipitation towards the end of the current 00Z TAF period.
Can`t rule out some erratic outflow winds, hail, and brief MVFR
conditions if any storms move directly over a terminal.

&&

.MARINE /FOR NEARSHORE WATERS OF WESTERN LAKE SUPERIOR/...
Issued at 153 PM CDT Sun May 24 2026

Southwest winds of 10-15 knots have helped to erode the
widespread fog that ruled the Lake last night and this morning.
These winds are expected to subside later this evening which
may allow for widespread fog to envelope the Lake once again.
Tomorrow afternoon and evening a line of storms may enter from
the Arrowhead as a cold front sags south. Some of these storms
may be strong to severe.

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

&&

.FIRE WEATHER...
Issued at 153 PM CDT Sun May 24 2026

Today marks the start of a warming trend for the Northland with
Tuesday expected to be the hottest day of the week. Highs will climb
into the 80s and some 90s for Tuesday. Min RHs will prove to be a
challenge over the next several days as southerly flow will help
promote increased dewpoints and diurnally driven cumulus in the
afternoon hours. Won`t be expecting bone dry conditions but
areas of 25% can`t be ruled out. Most likely across the Brainerd
Lakes area. Winds will follow the typical summer pattern of
increased gusts in the afternoon that taper off in the evening.
At this time we are not forecasting overly strong wind gusts
that would prompt critical fire weather conditions.

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

&&

.CLIMATE...
Issued at 153 PM CDT Sun May 24 2026

Record High Temperatures:

Monday, May 25:

      Record    Forecast
KINL: 88/1919   86
KBRD: 90/2018   88
KHIB: 87/2010   84

Tuesday, May 26:

      Record    Forecast
KBRD: 92/2018   90
KHIB: 88/1978   87


Record Warm Minimum Temperatures:

Tuesday, May 26:

      Record    Forecast
KASX: 60/1988   57

&&

.DLH WATCHES/WARNINGS/ADVISORIES...
MN...None.
WI...None.
MARINE...None.

&&

$$

DISCUSSION...Britt
AVIATION...Rothstein
MARINE...Britt
FIRE WEATHER...Britt
CLIMATE...Britt