textproduct: Duluth

KEY MESSAGES

- Frost Advisory for northern MN this morning.

- Rain chances return today with potential for strong to severe storms tonight.

- Monday will see continued rain and storm chances with the threat of severe storms limited to NW WI.

UPDATE

Issued at 159 AM CDT Sun May 17 2026

Areas along the Canadian border are flirting with freezing temperatures and most of northeast Minnesota has lowered to the mid thirties, and frost will likely be seen on elevated and grassy surfaces early this morning.

Models are consistent this morning of the dry air lingering from the last few days delaying the onset of showers this evening. The best chances for severe weather and minor flooding have shifted slightly southeast, with damaging winds and hail as the main hazards and an isolated tornado also possible.

CAMs have really backed off on the chances for showers and storms Monday afternoon and have delayed the second round of storms for later in the evening, where there may still be a narrow window for severe weather in our far eastern Wisconsin counties.

DISCUSSION

Issued at 302 PM CDT Sat May 16 2026

Current Conditions/Today:

Stark differences across the region this afternoon as a very slow stationary boundary drops south across northern MN. North of this boundary are mostly cloudy skies with temperatures staying in the 50s. South of this boundary we are seeing more sun leading to some drier conditions. Winds have also been gusting to around 30 mph with high temps climbing into the 70s. Fire weather concerns remain in place through the afternoon with a Red Flag Warning across the Brainerd Lakes region and east towards the Twin Ports and Pine County. Overnight clouds clear out and we will get some rapid radiational cooling. Low temps across northern Mn will drop into the mid and low 30s. A Frost Advisory has been issued.

Sunday:

Sunday is the beginning of a very active weather pattern for the Northland. An upper level trough digs into the desert southwest opening up the region to southwest flow and multiple low pressure systems moving out of the Rockies. The first low pressure system is expected to move across the Central Plains and towards the Northland through Sunday. Out ahead of this low pressure we will see winds shift to out of the east at the surface with a isentropic lift increasing across the region through the day. Cloud cover will thicken as rain aloft will try its best to saturate the column. With very dry conditions currently in play it will take awhile before rain starts to materialize at the surface. Our rain chances go from 40-50% in the afternoon to 60-80% in the evening and overnight.

Model guidance continues to waffle a bit with placement of key synoptic features but the latest high res guidance is starting to hone in on the main threat area being across portions of north central MN and into NW WI. This is a slight southeastward shift from what previous model runs were showing. The main initiation will be well off to our southwest in the afternoon across the Central Plains. Through the evening hours a strong low level jet is expected to fuel these storms as a cold front steers them northeast with one or more linear/bowing segments forming. The main threats at this time would be damaging winds and large hail. Depending on the low track the threat of tornadoes is non- zero across NW WI. Timing for the worst conditions currently looks to be 9PM through 5AM.

Monday:

Lingering precipitation will be in play for the morning hours with most of the rain still focused on NW WI initially. Depending on how the low tracks the previous night we may still have a lingering boundary over NW WI in the afternoon and evening hours which would prompt concerns for severe weather to develop once again. If we manage to get some surfaced based instability to recover after morning round of activity then we will be looking at an all hazards on the table type of afternoon and evening. But unlike the previous day, the threat window does not linger into the overnight hours. Additionally, most of the high res guidance is pulling most of the convection out of the Northland completely, will have to see how things trend.

Rain Amounts:

This forecast package saw a noticeable southeast shift in forecasted precipitation amounts with also an overall reduction in QPF totals. Previous guidance had chances of 2" rain in 48 hours as far west as the Brainerd Lakes region and up the North Shore, the latest guidance has reduced this to mainly NW WI with the aforementioned areas not only at a 30% of seeing greater than 2" Any thunderstorms that do manage to roll over an area will manage to produce some localized higher rain totals as the atmosphere will sport PWATs of over 1.25" Best timing for heavier rainfalls will be Sunday night with potential for another round Monday night.

Tuesday/Wednesday:

High pressure saunters in from the northwest with cooler air coming back into the Northland. An upper level shortwave moving through the region will keep PoPs in the forecast with some snow possible across the far north, accumulations not expected at this time.

Wednesday surface high pressure propagates to the Great Lakes with highs bouncing from in the 40s and 50s on Tuesday back up into the 50s and 60s for Wednesday.

AVIATION /06Z TAFS THROUGH 06Z MONDAY/

Issued at 1221 AM CDT Sun May 17 2026

VFR conditions are expected at all terminals for the next 18 hours. After 00Z, showers and storms will move north into the area. Onset time is a little uncertain as the precipitation will be fighting dry air, but southern terminals will see scattered precipitation by 06Z. Winds will increase in the morning and gusts up to 25 kts by the afternoon. LLWS is also expected ahead and with storms at HYR in the evening.

MARINE /FOR NEARSHORE WATERS OF WESTERN LAKE SUPERIOR/

Issued at 159 AM CDT Sun May 17 2026

Hazardous conditions are expected across western Lake Superior through the next 72 hours. Small Craft Advisories will transition into Gale Warnings today as northeast winds ramp up to 30 knots, with gale force gusts to 40 knots. This will cause waves building to 7 to 11 feet, with occasional waves up to 14 feet tonight. Conditions remain treacherous on Monday and Tuesday with additional gales and high waves expected, along with thunderstorm chances. Some storms could produce large hail in addition to the strong winds/gales.

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

FIRE WEATHER

Issued at 159 AM CDT Sun May 17 2026

Critical to near critical fire weather conditions from the previous days will ease today due to cooler temperatures and increasing clouds. However, easterly winds will become gusty, reaching 20 to 30 mph by this afternoon. The trend for dry air delaying the onset of showers and storms today has remained constant, meaning wetting rains will hold off until this evening. Heaviest rainfall has shifted to the southeast again slightly, but northwest Wisconsin will still see 1.5-2" while most of northeast Minnesota will see 0.5-1".

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

DLH WATCHES/WARNINGS/ADVISORIES

MN...Frost Advisory until 8 AM CDT this morning for MNZ010>012- 018>021. WI...None. MARINE...Small Craft Advisory from 7 AM this morning to 10 PM CDT this evening for LSZ121-148. Small Craft Advisory from 7 AM this morning to 10 AM CDT Monday for LSZ140. Small Craft Advisory from 7 AM this morning to 1 PM CDT this afternoon for LSZ141-142-150. Gale Warning from 1 PM this afternoon to 10 PM CDT this evening for LSZ141-142-150. Frost Advisory until 8 AM CDT this morning for LSZ142. Small Craft Advisory until 10 AM CDT this morning for LSZ143>145. Gale Warning from 10 AM this morning to 10 PM CDT this evening for LSZ143>145. Small Craft Advisory from 7 AM this morning to 1 AM CDT Monday for LSZ146-147.