textproduct: Marquette

KEY MESSAGES

- Hazardous winter weather will continue through tonight over the U.P. Light to moderate snow, along with gusty winds to 40 mph are expected over the Keweenaw tonight. Elsewhere a mix of freezing rain and light snow is expected. Ice accumulation of a glaze to one tenth of an inch is expected. Untreated surfaces could become slippery.

- Drier weather is expected on Thursday with temperatures rising above freezing for much of the U.P.

- Another low pressure system could bring hazardous winter weather to the U.P. again on Friday, in the form of heavy wet snow, freezing rain, rain and sleet.

DISCUSSION

Issued at 332 PM EST Wed Feb 18 2026

Afternoon GOES WV imagery and RAP analysis place the well stacked mid level trough and surface low over central MN, with sfc obs showing a occluded front extending from NW WI toward Green Bay, WI. The radar mosaic has the main synoptic snow lifted out over Lake Superior, but satellite imagery and the radar mosaic highlight an additional round of showers along elevated instability and an embedded shortwave lifting overhead prior to the dry slot behind it. These showers could bring a wintry mix of snow/freezing rain or rain. Ice accumulations would be less than 0.1 inch and snow accumulations would be limited to a half inch.

Moisture fills back in this evening as the mid level trough pivots overhead. While the instability drops off, a second round of snow and possibly rain/freezing rain is expected. This time with better snow accumulations of 1-2 inches of snow; a light glaze of ice is possible. Given significant snow totals are mostly over, but wintry mix could create slick conditions overnight into Thursday, opted to downgrade most to Winter Weather Advisory through 7 AM EST. Kept the Keweenaw in a Winter Storm Warning for heavier snowfall (additional snowfall of 3-9"), stronger winds and blowing snow concerns still on going through tonight. Lows tonight will mainly in the 20s.

By Thursday morning, the low will be weakening over Ironwood, placing lingering snow showers mainly over the Keweenaw. Additional amounts of 1-3 inches in the Keweenaw with 1 inch or less over the northern tier. Highs will be in the 30s to low 40s, warmest south. Temps then settle once again into the 20s.

Attention then turns to another low pressure that will move out of the central Rockies (Colorado low) tonight and track toward the Upper Great Lakes by Friday morning. This system has the potential to bring more heavy, wet snow to portions of the U.P along with a mixed bag of precipitation, especially central and east, of freezing rain, sleet and snow. Forecast confidence is low at this time as guidance diverges on the track of the system along with a fairly narrow axis of heavier precipitation. Current probabilities for 3+ inches of snowfall are in the 60-70% range over the central and western U.P. Probabilities for >6" are still rather low, likely due to significant differences among guidance and the rather narrow axis of heavy snow. Confidence is not high enough for winter headlines at this point.

Chances for snow continue through the remainder of the weekend as the low pressure weakens over the Great Lakes yielding lake enhanced to lake effect snow showers (25-50% chance). Drier weather is favored into early next week as high pressure and a mid level ridge move in from the northwest, but an active weather pattern looks to end the month with several troughs emanating into the Great Lakes. This is noted well in the CPC 6-10 day outlook of 40-50% chance for above normal precip. Near to above normal temps look to accompany this pattern.

AVIATION /18Z TAFS THROUGH 18Z THURSDAY/

Issued at 1232 PM EST Wed Feb 18 2026

IFR, LIFR and VLIFR are expected through the TAF period as a winter storm continues to impact the U.P. Heavy snow was lifting north through CMX early this afternoon with VLIFR / airport minimums. Though the snow will diminish in intensity this afternoon, upslope flow will keep fog over the airport along with periodic snow showers through tomorrow morning. Snow was exiting the SAW but freezing drizzle is expected to develop along with fog and periodic snow showers through tomorrow morning. IWD will be flirting with the freezing mark this afternoon and with mainly rain and a few snow flakes possible. Winds become southeasterly tomorrow with improving conditions late in the TAF period.

MARINE

Issued at 332 PM EST Wed Feb 18 2026

Easterly gales of 35-45 kts lake-wide with a few storm force gusts to 50 kts over the far western arm of the lake continue into this evening. Winds slowly taper off from south to north across the lake through Thursday morning as a low pressure system weakens near western Lake Superior. As this system continues to dissipate and another low pressure moves into the Great Lakes for Friday, expect winds over the west half of the lake to take on a more northerly component with 20-30 kt winds lakewide. There is a 20-40% chance for gales to 35+ kts over the east half of the lake on Friday. With colder air returning late this weekend into early next week and periods of 20-30 kt winds, moderate to heavy freezing spray likely returns Sunday into Monday.

MQT WATCHES/WARNINGS/ADVISORIES

Upper Michigan... Winter Storm Warning until 7 AM EST Thursday for MIZ001-003.

Winter Weather Advisory until 7 AM EST /6 AM CST/ Thursday for MIZ002-009>012-084.

Winter Weather Advisory until 7 AM EST Thursday for MIZ004>007- 013-014-085.

Lake Superior... Storm Warning until 7 PM EST /6 PM CST/ this evening for LSZ162.

Gale Warning until 1 AM EST Thursday for LSZ242-251-263-267.

Gale Warning until 7 AM EST Thursday for LSZ243>250-264>266.

Lake Michigan... Gale Warning until 4 PM EST this afternoon for LMZ248-250.