Marine Weather and Tide Forecast for Grand Marais, MN

DISCUSSION
Issued at 1259 PM CDT Tue Apr 14 2026

Current Conditions/Today and Tonight:

Early afternoon radar and and satellite imagery showed an area of showers with embedded thunderstorms across the arrowhead of Minnesota. These were located ahead of a compact little shortwave trough that was skirting along the MN/CA border. For the rest of the afternoon and evening, expect dry conditions as this system exits to the east. Meanwhile, wind remain fairly light under the influence of a baggy pressure gradient, and that will set the stage for another night of low clouds and fog.

Wednesday/Thursday:

A couple of days of dry and warm weather are in store for the Northland on Wednesday and Thursday. Wednesday could start out cloudy and foggy, so temperatures depend on how quickly we can clear out. On Thursday, an area of low pressure will organize across the High Plains, and this will bring southerly winds across the region. Current humidity forecast is around 30 to 35 percent, so will have to watch the trends for fire weather concerns. Otherwise expect spring-like weather with highs in the 60s to near 70, except along Lake Superior.

Friday/Monday:

This low pressure system across the High Plains will track eastward on Friday as a longwave trough amplifies over the central CONUS. That will bring surge of warm and moist air across the Upper Midwest, while drier moves on top of it. This will set the stage for thunderstorms Friday afternoon and evening ahead of an approaching cold front. As of now, the most likely area for storms is along I-35 and east. A few storms could be strong to severe owing to the favorable deep layer shear and 1000 to 2000 J/kg of instability. The primary threat will probably be severe hail, but there is a wind threat given the unidirectional shear profile.

In the wake of this front, expect much cooler temperatures as northwest wind ushers a return arctic air. Meanwhile the overall storm system will become better organized, and an area of deformation precipitation will develop Friday night into Saturday. Thermal profiles support a rain-to-snow transition.
Any snow accumulation should be less than an inch of slushy wet snow on grassy surfaces. One would expect lesser snow amounts if this falls during the day on Saturday given the April sun angle and warm pavement temperatures. Snow will end Saturday night, but the cool air will last through the weekend with highs in the lower 40s Sunday and lower 50s Monday.

AVIATION /00Z TAFS THROUGH 00Z THURSDAY/
Issued at 645 PM CDT Tue Apr 14 2026

After partial clearing and lifting ceilings at inland terminals this evening, predominant IFR to LIFR conditions are again forecast for most terminals tonight. Dense fog is very likely at shoreline and MN Borderland terminals tonight into 12-15Z Wednesday. Ceilings and visibility improve from 15 to 20Z Wed.
with VFR conditions late tomorrow afternoon into tomorrow evening. Expect light and variable easterly winds through this TAF period.

MARINE /FOR NEARSHORE WATERS OF WESTERN LAKE SUPERIOR/
Issued at 212 PM CDT Tue Apr 14 2026

Scattered rain and thunderstorms are no longer expected today, as they have shifted to the northeast. There is still dense fog.
For the next few days, winds will be light. Waves will be less than 2 feet both Wednesday and Thursday. On Friday, southerly winds will bring high waves along the north shore. A strong cold front will bring northwest winds Friday night into Saturday, with waves 3 to 5 feet or higher, especially along the south shore on Saturday.

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

FIRE WEATHER
Issued at 212 PM CDT Tue Apr 14 2026

The fire weather risk is low today and Wednesday. The rest of today will have high RH today due to low clouds and high RH. On Wednesday, RH will be a bit lower, but winds will remain light.

On Thursday, southerly winds will increase to around 20 mph and RH values will drop to around 30 to 35 percent. Southerly winds will be stronger on Friday, but humidity will increase. A cold front will pass through on Saturday and bring northwest winds and cooler temperatures for the weekend.

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