textproduct: Duluth

KEY MESSAGES

- Scattered rain showers depart the region this evening

- Rain chances return Thursday afternoon with some storms possible overnight into Friday. No severe weather expected at this time.

- Near critical fire weather conditions possible Wednesday with dry conditions. Very dry and windy conditions possible on Friday, Red Flag Warnings may be needed.

DISCUSSION

Issued at 219 PM CDT Tue May 12 2026

Current Conditions/Today:

Surface low pressure is moving across northern MN this morning and will move into northern WI this afternoon. On the backside of this low we see lingering moisture returns mixed with some decent mid level lapse rates that could generate some scattered showers this afternoon across northern MN and into NW WI. Thunderstorm potential will be largely tied to the location of the the cold front which current high res guidance has largely pushing out of the northwest WI by peak heating.

Wednesday:

Surface high pressure sets up for a quiet Wednesday. Dry and warmer air filters in from the west with highs expected to climb into the 60s with some 70s possible. Min RHs will also fall into the 20s, and despite having some rain last night, most of the measurements coming in are less than 0.10" across the west. Another near critical fire weather day will be possible. Along our eastern half we will have some lingering moisture available to produce some diurnally driven clouds and keep the area in the low to mid 60s.

Thursday/Friday:

A vertically stacked low moves into the Canadian Prairies on Thursday as high pressure departs to the east. Warm southerly flow through the day will help to push temperatures into the 70s with the exception being near Lake Superior where the cool waters will keep temps 10-15F cooler. The mature low's warm front will advect in from the west in the afternoon and evening hours. Each new run of high res guidance continues to gradually slow the arrival time of the line of rain with the current rendition largely entering our west around 4-5PM. Weak instability initially with its arrival could prompt some embedded thunderstorms. Overnight the low level jet ramps up increasing MUCAPE with an area of steep mid level lapse rates developing. This elevated convection could generate some small hail, but severe weather is not expected at this time.

There is a high degree of uncertainty for Friday's forecast. The 12Z suite of deterministic guidance shows little agreement on the placement of key synoptic features such as the mature low, the main cold front, and a secondary cold front. Best guess at this time is that the main cold front (which would be the focal point for stronger storms) will be pushing out of NW WI. Dry air filtering in behind this departing system may lead to some fire weather concerns. Model soundings show mixing up to 7000 ft with very windy conditions possible, Red Flag Warnings may be needed. The secondary cold front will be in the vicinity of the International Border which could generate some light showers. At the moment the NBM is not carrying any noticeable PoPs for Friday afternoon and evening. But the LREF has at least 20-30% across northern MN and into NW WI.

Weekend:

A frontal boundary stalls out over the region on Saturday with our southern counties warming into the the 70s and northern counties staying in the 60s. Cluster analysis highlights a deepening upper level trough into the four corners on Sunday. As this trough pushes into the Midwest we could see a very active pattern return late Sunday into early next week.

AVIATION /18Z TAFS THROUGH 18Z WEDNESDAY/

Issued at 1229 PM CDT Tue May 12 2026

A surface low pressure is moving across the Northland today leading to some scattered showers. Cloud cover will be increasing with areas of MVFR ceilings expected. As the low pressure moves southeast expect winds to turn to out of the northwest. VFR conditions will return late this evening as the system departs to the southeast.

MARINE /FOR NEARSHORE WATERS OF WESTERN LAKE SUPERIOR/

Issued at 219 PM CDT Tue May 12 2026

Surface low pressure is moving into NW WI this afternoon. Easterly winds will turn to out of the north and northwest this evening. Small Craft Advisories will also taper off this evening. Next chance for more widespread impactful winds will be Thursday night into Friday as strong southwesterlies sweep across the Lake.

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

FIRE WEATHER

Issued at 219 PM CDT Tue May 12 2026

Low fire weather concerns today as a surface low moves across the region with some isolated rain showers. Tomorrow high pressure filters in with sunnier skies expected, especially across our west. Min RHs are expected to drop into the low 20s. Some of the more aggressive models have Min RHs falling into the teens. This will lead to some near critical fire weather conditions given the lack of rain and wind gusts in the lower teens.

Thursday afternoon rain chances return from the west. Not expecting a soaking rain though with only isolated areas receiving noticeable amounts due to a few thunderstorms. Friday is looking very concerning from a fire weather standpoint. In the wake of a cold front dry air filters in across the region with very windy conditions expected. Red Flag Warnings may be needed. 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 11 PM CDT this evening for LSZ140- 141. Small Craft Advisory until 7 PM CDT this evening for LSZ143>146.