textproduct: Marquette

KEY MESSAGES

- Seasonably cold temperatures this weekend with highs mainly in the teens and lows in the negative single digits.

- Light lake effect snow showers persist over the northwest wind snowbelts into Sunday.

- A warmer pattern with daily high temperatures in the 30s and 40s is likely this coming workweek.

DISCUSSION

Issued at 111 PM EST Sat Feb 28 2026

Early afternoon GOES satellite imagery reveals a broad longwave trough draped across the northern Great Lakes with a few weak embedded shortwaves within. Chilly NW flow characterized by 850 mb temps between -24 and -21 C is supporting lake effect snow showers downwind of Superior. In the west half, model soundings and satellite imagery suggest plenty of dry air working to limit LES intensity, cutting off lake induced eq heights between 4-6k ft with plenty of sub-cloud sublimation action as well. Further east, the greater fetch as enabled a more banded structure to LES across Alger Co, though it appears lightening winds and aforementioned dry air entrainment may be having the same effect, as radar returns show more LES bands becoming more showery/cellular in nature. An additional 1-2" of snow is possible mainly across Alger/Luce counties through tonight. As sfc high pressure draws closer to the western lake tonight and into tomorrow morning, CAMs suggest a convergence zone setting up somewhere between Munising and Grand Marias. This may lead to a narrow band of moderate LES impacting portions of M-28 east of Munising tomorrow morning. Should this occur, it would be rather short lived as CAMs quickly kick LES showers east and eventually out of the UP through the afternoon. Otherwise, high pressure overhead Sunday and Monday will keep the rest of the area fairly quiet. Temps rebound back mostly above freezing on Monday amidst gusty southwest winds.

Zonal flow sets up for next week with systems mainly only grazing the UP the first half. More widespread PoPs, albeit still on the low side (20-40%), set up for the later half of the week as deeper waves and stronger surface lows begin to move into the Upper Midwest. Deterministic guidance and their ensemble counterparts still show significant spread in the evolution of shortwaves lifting through the Great Lakes and High Plains. Given the uncertainty yet, a wintry mix is still possible. The pattern next week favors a warm up (65- 75% chance for above normal temps per the latest CPC 6-10 day outlook), with highs once again returning to the 40s for many. Lows initially in the upper teens to 20s early next week push near freezing Wednesday/Thursday nights.

AVIATION /18Z TAFS THROUGH 18Z SUNDAY/

Issued at 1245 PM EST Sat Feb 28 2026

Lake induced cloud cover is producing MVFR ceilings over the northern tier of the UP today, with snow showers mostly relegated to the eastern half as northwest flow lingers in the wake of the departing low pressure system. Expect a gradual improvement towards VFR through the rest of the day as high pressure builds in from the west, with VFR conditions then expected to prevail for the remainder of the TAF period. However, HREF guidance does maintain around a 40% probability for MVFR cigs to redevelop tonight into Sunday morning at KIWD and KCMX. Northwest winds around 10 kt at the terminals as of 18z Sat will drop to around 5 kt this evening and remain light through the rest of the period.

MARINE

Issued at 302 AM EST Sat Feb 28 2026

Northwest gales of 35-45 kts over the east half quickly diminish this morning as the strong low level jet departs and high pressure builds in from the northwest. Downgraded the east to a Gale Warning through 7 AM EST and canceled the west Gale Warning early. Winds over the west fall below 20 kts by this afternoon with winds around 20-25 kts in the east into the evening. Winds over the east fall below 20 kts tonight, with lakewide winds below 20 kts through Sunday night. As a result, heavy freezing spray diminishes from west to east today. Trimmed up the end time for the eastern zones Heavy Freezing Spray Warning, otherwise maintained those hazards as inherited.

Southerly winds increase on Monday to 20-30 kts ahead of a surface trough Monday night. There is a 15-30% chance for gales to 35 kts over the east and near Isle Royale Monday afternoon and evening. Winds become northerly and fall below 20 kts Tuesday morning.

MQT WATCHES/WARNINGS/ADVISORIES

Upper Michigan... None. Lake Superior... Heavy Freezing Spray Warning until 4 PM EST this afternoon for LSZ245>248-265.

Heavy Freezing Spray Warning until 10 PM EST this evening for LSZ249>251-266-267.

Lake Michigan... None.