Duluth, Minnesota 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

303
FXUS63 KDLH 250540
AFDDLH

Area Forecast Discussion
National Weather Service Duluth MN
1240 AM CDT Fri Apr 25 2025

.KEY MESSAGES...

- Rain showers are expected tonight into Friday morning over northwest
  Wisconsin. Little to no precipitation will occur over
  northeast Minnesota over the same time period.

- Dry conditions are expected Friday afternoon into Saturday.
  Near- critical fire weather conditions may be possible due to
  low relative humidity on Saturday.

- Rain chances arrive on Sunday and continue into Monday. There
  is a 15% chance for strong to severe thunderstorms on Monday,
  for areas along and south of US-2.

&&

.DISCUSSION...
Issued at 308 PM CDT Thu Apr 24 2025

Fairly benign conditions have been observed across the CWA early
this afternoon with varying amounts of cloud cover. Clouds have been
advecting in from the south this afternoon ahead of an approaching
shortwave trough. In addition to the shortwave approaching from
southern Manitoba, low pressure will continue propagating eastward
through the mid-Mississippi valley tonight into Friday morning. An
area of light rain that has already developed within the baroclinic
zone ahead of the shortwave trough axis will advect north into
northwest WI late this afternoon into tonight. Total QPF from the
system tonight into Friday will be around 0.5" or less.

Expect rain to come to an end across the CWA by Friday afternoon as
the axis of the shortwave pivots through. Dry and mostly sunny
conditions are expected Friday afternoon into Saturday as high
pressure builds over the central CONUS. Model soundings from CAMs
and the GFS show that a substantial dry layer will likely develop
over the area on Saturday. With the potential for this dry air to
mix to the surface, near-critical fire weather conditions may be a
concern for Saturday as min RH drops to around 25%. Fortunately,
fire weather concerns are somewhat mitigated by the relatively light
winds that are expected under the high pressure.

Attention turns towards another active period of weather Sunday into
Monday as a cutoff low over the Great Basin region rejoins the jet
stream on Sunday and propagates towards the Midwest. Sunday will see
rain shower chances arrive into the area as southerly flow provides
strong WAA and ample moisture advection to the CWA. This initial
round of precipitation on Sunday will most likely be rain with
the potential for isolated thunderstorms.

Thunderstorm chances ramp up late Sunday into Monday as steeper mid-
level lapse rates in excess of 8 degC/km move into the CWA. Moisture
advection into the area will continue to be favorable, with PWAT by
12z Monday being as high as 1-1.4" (around the 97th percentile of
NAEFS climatology). Expect this strong Gulf moisture advection to
continue through the afternoon with high temps in the afternoon
reaching the low 70s for the southern half of the CWA. These warm
temps combined with dewpoints reaching the low 60s and steep mid-
level lapse rates will potentially increase MUCAPE in excess of 1000
J/kg for the southern half of the CWA. This moderately favorable
instability environment will occur in conjunction with strong 0-6km
bulk shear of 50+ knots. At this time there is a fair amount of
uncertainty regarding how far north the instability can reach and
whether or not a sizable cap appearing in model soundings in
the low-levels can be overcome. GEFS and EPS ensemble MSLP
centers show a decent amount of spatial spread, which will have
large implications on the placement of highest instability and
the northward extent of possible severe convection. The Day 5
convective outlook from SPC still reflects a 15% chance for
severe thunderstorms for areas along and south of US-2 on
Monday. This will be a day to closely monitor as we head through
the weekend and forecast confidence increases.

&&

.AVIATION /06Z TAFS THROUGH 06Z SATURDAY/...
Issued at 1240 AM CDT Fri Apr 25 2025

VFR conditions across the region early this overnight. Widespread
light rain continues over much of northwest Wisconsin during
the current overnight hours into Friday morning before exiting
east, with some MVFR ceilings expected during the morning before
clearing skies lead to a return of VFR conditions starting in
the afternoon. Fro central into northeast Minnesota, a thinner
band of VFR sprinkles/light rain will move east through the
overnight hours, and should precipitate at BRD and possibly at
DLH. Duluth has a 30-50 percent chance to see MVFR ceilings in
the morning. Otherwise, expect VFR conditions to prevail for
central to northeast Minnesota terminals. Winds start out light
and variable then turn northerly today with gusts of 15-18 knots
during the afternoon and become light and variable again this
evening and tonight.

&&

.MARINE /FOR NEAR SHORE WATERS OF WESTERN LAKE SUPERIOR/...
Issued at 308 PM CDT Thu Apr 24 2025

Light northeast winds will continue through the afternoon today.
Winds will generally maintain this direction through Friday night
into Saturday morning with speeds of 5 to 10 kts across western Lake
Superior. There will be some light rain along the South Shore zones
tonight that will be exiting Friday morning. The next chance for
hazardous conditions for small vessels won`t arrive until Monday
into Tuesday as winds increase along with chances for showers and
thunderstorms.

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

&&

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

&&

$$

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