textproduct: Duluth

KEY MESSAGES

- Lingering rain in the Arrowhead and northwest Wisconsin will end this morning.

- Near-critical fire weather conditions are expected in north- central Minnesota today due to low relative humidity.

- Cooler weather over the weekend with a chance for light rain Saturday night.

- A larger system may bring widespread rain and perhaps a few flurries next week.

UPDATE

Issued at 256 AM CDT Fri Apr 24 2026

Current Conditions and Early Morning Outlook: A cold front is working its way through the Northland this morning, and pretty much all of northeast Minnesota except the tip of the Arrowhead has switched over to post-frontal northwesterly flow. Low clouds are quickly mixing out as gusty winds and drier air move in. Ahead of and along the front, rain and some embedded thunderstorms continue with plentiful moisture feeding in from the south. Rainfall amounts for the event so far have been about as expected with generally less than an inch on the Minnesota side (though a few places, including around the Twin Ports, have seen some 1"+ amounts). In Wisconsin, there are several 1-2" observations and even 2.21" so far in Odanah. Dual-pol estimates suggest localized pockets approaching 3", and we have issued a few flood advisories where higher rates have occurred.

For the rest of the morning, we expect that additional rainfall amounts and rainfall rates will be more tame with a general loss of widespread convection. We will still keep an eye on the localized minor flooding potential with rain spreading into the Arrowhead for several hours, but the situation is evolving as expected and any flooding impacts are expected to be minor and few and far between. As the cold front continues east today, rain is expected to gradually taper off from southwest to northeast this morning.

Today: Skies are expected to clear out this morning and plenty of sunshine is expected today. Blustery northwest winds are expected through the morning behind the front, but they should calm down gradually into the afternoon with ridging developing. Where it didn't rain and skies clear out first, low relative humidity is expected into this afternoon. Near-critical fire weather conditions are expected for much of north-central Minnesota this afternoon with humidity falling to 20-30 percent.

Tonight and This Weekend: Expect temperatures to fall to around freezing in the borderland tonight, then fairly quiet weather on Saturday with increasing clouds ahead of an incoming stream of moisture with dual Gulf/Pacific origins. Instability looks pretty weak with this, so this may end up being more of a light rain event without much for thunder chances starting late Saturday afternoon and lingering into early Sunday morning for a good chunk of the Northland (though a few rumbles of thunder can't be ruled out).

We should get more east/southeast flow on Sunday, resulting in warmer conditions (highs in the 60s) inland but keeping the lakeshore areas cooler in the 50s.

DISCUSSION

Issued at 225 PM CDT Thu Apr 23 2026

This afternoon and tonight...

Skies cleared over northwest Wisconsin this morning and temperatures rose into the low to middle 70s. Farther west overcast skies persisted keeping temperatures in the low to middle 60s. Isentropic lift over Minnesota supported a slowly expanding area of showers over central and southwest Minnesota stretching north to just west of Duluth. Coverage of showers and storms will increase through the remainder of the afternoon.

GOES-East infrared and visible imagery revealed an area of weak subsidence over southwest Minnesota into western Iowa. Visible imagery featured a narrow area of clearing just ahead of the storms which developed between 1830Z and 1915Z. There will likely be a slight increase in MLCAPE in that clear slot.

Storms over central and southwest Minnesota may become surface- based as the cap erodes and MLCAPE increases. RAP sounding from near St. Cloud reveals cyclonic curvature in the hodograph between the surface and 2 km with the greatest curvature in the 0-1km layer. The tornado potential remains smaller than the risk of hail and damaging winds though it may increase as the clearing expands farther north. The sunshine and warmer temperatures will support MLCAPE of 1000-1500 J/kg by late afternoon over northwest Wisconsin. A capping inversion around 700 mb will gradually erode by early evening which will enable storms to become surface based. Forecast hodographs feature limited directional shear and trajectories are nearly stacked above 3 km. Storms will benefit from low- level ascent enhancement though parcel evacuation will be limited in the top half of the storm. Thus precipitation will fall back through the updraft limiting storm intensity. Initial discrete storms will pose the greatest hail and tornado risk while later storm mergers and cold pool interactions will support a shift toward damaging wind risk with time. Hail up to quarter size, wind gusts up to 70 mph, and a small risk of one or more tornadoes are the threats through this evening. There is a small risk of one or two storms producing hail up to ping-pong ball size.

Heavy rainfall remains a concern due to PWATs over an inch, the moist profiles and the potential for training storms. The greatest risk of excessive rainfall and minor flooding is over northwest Wisconsin and the Minnesota Arrowhead (where there remains noteworthy snow pack and recent melting).

Rain and storms will become widespread over the eastern half of the Northland during the evening and will gradually shift eastward overnight ahead of the approaching cold front. Temperatures will dip into the middle and upper 30s over north- central Minnesota to around 40 degrees in the Arrowhead and low to upper 40s in northwest Wisconsin.

Friday through the weekend...

The cutoff low will remain over the Canadian Prairies. Rain and a few embedded thunderstorms may still linger over the Arrowhead and portions of northern Wisconsin and western Upper Michigan. Temperatures will trend cooler with near-normal highs from the middle 50s to the low 60s. Very dry conditions are forecast with afternoon humidity values between 20 and 35 percent in Minnesota west of the I-35 corridor north to the Canadian border. The Arrowhead and much of northwest Wisconsin will not dry out as much due to clouds and precipitation loiter longer over those areas. Lows Friday night will dip below freezing north of a line from Northome to Two Harbors (except shoreline areas of Lake and Cook counties) and the middle 30s farther south.

Temperatures remain near to slightly above normal for Saturday and Sunday. Both days appear to be dry with low RH values forecast. The latest guidance hints at a chance of showers or possibly a thunderstorm or two Saturday night and early Sunday morning somewhere over the northwest quarter of Minnesota. Rain amounts would be small, less than a tenth of an inch. GFS is a bit more broadbrushed with precipitation from west-central Minnesota to northeast Minnesota.

Monday through next week...

The cutoff low over the Canadian prairies is forecast to drift slightly farther north early next week. Deterministic solutions point to a low pressure system taking shape over the Midwest Monday and Tuesday. Rain and perhaps a few thunderstorms are likely during that period. Ample poleward moisture advection with that system raises a concern about minor flooding depending on the location and duration of the rainfall. The closed low is forecast to meander around the Canadian prairies and northern Plains into late next week before it advances east toward New England. Additional precipitation chances and near to below normal temperatures are forecast. There is a potential for a few snowflakes Thursday and Friday.

AVIATION /18Z TAFS THROUGH 18Z SATURDAY/

Issued at 1246 PM CDT Fri Apr 24 2026

VFR conditions prevail through the TAF period. Northwest winds gusting to around 15 kt will weaken later this afternoon and become light and variable tonight and light out of the south for Saturday. Clear skies for most of the area this afternoon and evening, though increasing mid and high-level cloud cover will move over much of the Northland starting tonight and continuing into Saturday morning.

MARINE /FOR NEARSHORE WATERS OF WESTERN LAKE SUPERIOR/

Issued at 256 AM CDT Fri Apr 24 2026

Breezy northwest winds are expected through the early afternoon. A Small Craft Advisory remains in effect for the North Shore for breezy northwest winds this morning and lingering wave heights up to 2 to 5 ft from onshore winds earlier. The end time of the advisory has been trimmed to end this afternoon as both winds and waves are expected to simmer down by then.

No major marine concerns are expected again until early next week when a broad low pressure system could produce gusty winds.

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

FIRE WEATHER

Issued at 256 AM CDT Fri Apr 24 2026

Near-critical fire weather conditions are expected this afternoon and early evening for north-central Minnesota as relative humidity is expected to fall into the 20 to 30 percent range. Winds are not expected to be very strong this afternoon, but the dry air mass alone will promote these near-critical conditions. There is some question on how far east the low RH values may spread into places that received rain, but right now it's looking like places west of the I-35 and US-53 corridors in Minnesota have the best chance of seeing low RH this afternoon.

On Saturday, there may be some pockets of low RH down to around 25% for parts of northeast Minnesota, but the forecast generally does not look as dry as today with increasing clouds expected in the afternoon. Expect a chance for light rain Saturday night, which may bring a few hundredths up to a tenth or two of rain. With this moisture, RH on Sunday may not fall below 30%.

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 PM CDT this afternoon for LSZ140>143.