textproduct: Marquette

KEY MESSAGES

- Light snow is expected over the Keweenaw, central and eastern U.P. 1-3" of snowfall is expected.

- Light to moderate lake effect snow will develop late tonight into Sunday for the north wind snow belts. Wind gusts of 35-40mph near Lake Superior on Sunday will result in poor visiblity at times due to the combination of snow and blowing snow.

- A clipper low could bring widespread snow to the U.P. on Tuesday. The exact track of the low is still uncertain.

- More normal winter-time temperatures continue through midweek.

DISCUSSION

Issued at 236 PM EST Sat Feb 21 2026

This afternoon model analysis showed a 1013mb sfc low parked over Lake Huron with an inverted trough extending northwest well into Ontario. Radar reflectivity showed a band of light snow over the central and eastern U.P. as well as the Keweenaw, flurries had been reported at times elsewhere. Temperature were cooler today, especially for the central and western U.P. where temperatures were in the low to mid 20s.

Tonight through Sunday the sfc low over Lake Huron will continue to weaken and then open up as a stronger low forms along the mid- Atlantic coast. The band of snow over the central portion of the U.P will continue to meander a bit east and west overnight and weaken through Sunday morning as warm air advection dissipates. However, as the trough starts to move south through the U.P overnight cold air advection will bring 850mb temperatures down to -15C in the west and -11C in the east by Sunday morning. 850mb temps fall further through the day, as cold as -19C. This will result in increasing lake induced instability along with deepening inversion heights to around 5kft. Over the central part of the lake deep moisture will remain in place, with saturation through 300mb until Sunday evening. Expect widespread light to moderate lake effect snow to develop in the north to northwest wind snowbelts. Instability over the land will be sufficient to allow the bands to extend well inland on Sunday and event into Sunday night for areas between Lake Superior and Lake Michigan. Lake effect will wind down through the day on Monday as winds weaken and turn southerly ahead of an approaching clipper.

Snow amounts with the snow band over the central U.P and Keweenaw look to be in the 1-3" range through late this evening. Thereafter there could be a bit of a lull before lake effect ramps up Sunday morning. 24hr snowfall amounts from the lake effect are generally in the 2-5" range (approx midnight tonight until midnight Sunday) in the north wind snowbelts, with amounts as high as 6" in areas of terrain enhancement. Some of the CAMs like the HRRR are a bit more robust with snowfall amounts over 10" in the high terrain. Blowing snow could also be an issue, especially near the Lake Superior shoreline where winds will be sustained up to 25 mph with gusts to near 40 mph. With the dry and fluffy nature of the lake effect snow and ice along the shorelines visiblity could be very low for locations along the lake, especially between Marquette and Munising where shoreline ice will increase the fetch of blowing snow. Forecast snow amounts are a little modest with respects to typical criteria, however, with the addition of blowing snow travel could be difficult at times, with visiblity changing rapidly over short distances. Those planning to travel through early Monday should be prepared for difficult travel at times under the heavier snow bands.

By late Monday night a clipper will approach the area with snow chances increasing in the far west and across the rest of the U.P by Tuesday morning. Light to moderate snow will be possible with this system but the exact track and thus placement of the heaviest snowfall is still uncertain. In the wake of the clipper expect lake effect snow Tuesday night into Wednesday. Highs will mainly be in the 20s through Thursday.

For those looking for warmer weather, temperatures of Friday will likely be well above freezing, into the lower 40s. However it may be short lived as another cold front looks to push through the area for next weekend.

AVIATION /18Z TAFS THROUGH 18Z SUNDAY/

Issued at 1252 PM EST Sat Feb 21 2026

Light to moderate snow continues over the Keweenaw and central U.P. through the evening and into the overnights hours as lingering synoptically forced system snowfall transitions to more of a lake effect regime. IFR cigs/vis are expected to persist at CMX/SAW while IWD remains in MVFR. Once we fully transition to lake effec snow overnight through tomorrow morning, IFR should be the predominant category across all sites with periods of LIFR vis in blowing snow at CMX. N-NW winds 15-20 kts increase to 20-30 kts late tonight.

MARINE

Issued at 236 PM EST Sat Feb 21 2026

Northwesterly winds to 25kt tonight will turn north on Sunday and increase to gales of 35kt over the central part of the lake as a reinforcing cold front moves through. Heavy freezing spray will also develop over all but the far western part of the lake. Winds fall below gale late Monday night but remain strong to 30kt with heavy freezing spray continuing. The pressure gradient begins to relax on Monday ahead of an approaching clipper, with winds falling below 20kt by Monday afternoon and becoming southerly late Monday night. Southerly winds on Tuesday as high as 30kt in the east can be expected but will shift northwest early Wednesday morning as another cold front pushes through the area. Moderate freezing spray will accompany the northwest winds. Ridging build in for Thursday with winds turning southwesterly and falling below 20kt.

MQT WATCHES/WARNINGS/ADVISORIES

Upper Michigan... Winter Weather Advisory until 1 AM EST Monday for MIZ001- 003>006.

Winter Weather Advisory from 10 PM EST /9 PM CST/ this evening to 1 AM EST /midnight CST/ Monday for MIZ002-009.

Winter Weather Advisory until 7 PM EST this evening for MIZ013.

Lake Superior... Heavy Freezing Spray Warning from 7 AM Sunday to 1 AM EST Monday for LSZ242-263.

Heavy Freezing Spray Warning from 1 AM Sunday to 1 AM EST Monday for LSZ243-244-264.

Gale Watch from Sunday afternoon through late Sunday night for LSZ243-244-264.

Heavy Freezing Spray Warning from 1 PM Sunday to 1 AM EST Monday for LSZ245>250-265-266.

Gale Watch from Sunday afternoon through late Sunday night for LSZ245>248-265.

Gale Watch from Sunday afternoon through Monday morning for LSZ249-250-266.

Heavy Freezing Spray Warning from 4 PM Sunday to 1 AM EST Monday for LSZ251-267.

Lake Michigan... None.