textproduct: Marquette

KEY MESSAGES

- Widespread snowfall is expected Tuesday through Wednesday morning, with lake effect snow trailing downwind of Lake Superior Wednesday. Several inches of snowfall are possible, especially over the northern half of the U.P. but uncertainty remains in the locations and amounts. A Winter Storm Watch is in effect for Marquette County where confidence is higher for snowfall of 3-9 inches, highest amounts of the higher elevations.

- Another widespread snowfall and windier event may impact the U.P. Thursday night and Friday.

DISCUSSION

Issued at 309 PM EDT Mon Mar 9 2026

Early this afternoon sfc analysis showed low pressure exiting the region into far eastern Ontario. A trailing cold front was pushing across the U.P. Ahead of the front southerly winds were helping to keep temperatures well above average, starting out in the 40s this morning and now in the low 60s over Menominee and Delta Counties. Behind the front temperatures were falling slowly or holding steady in the 40s. Winds gusted to 49 mph with the fropa at Copper Harbor this morning. Satellite imagery showed passing, mainly mid and high level clouds that were filtering the sunlight at times but overall sunshine was abundant through the day.

A progressive, active pattern is expected through the coming weekend over the northern tier of the U.S. with multiple troughs moving through an otherwise zonal flow. This will bring opportunities for accumulating snowfall through the weekend tough uncertainty still remains in the timing and placement of the heaviest precipitation. NBM probabilities for 6"+ snowfall in 24 hrs for the potential systems Thursday/Friday and Saturday/Sunday are in the 30-50% range. For the upcoming system Tuesday night the highest chances are focused on the higher terrain of Marquette County, discussed below. Temperatures through the period are generally near normal (upper 20s to mid 30s) through there is the potential for much colder weather starting late in the weekend into early next week.

Tonight into Tuesday a baroclinic zone will set up from west to east across the Upper Great Lakes with the sfc cold front slowly sinking southwards. Weak forcing along the front will create a band of light snow over the western and parts of the north central U.P where an inch or two of snowfall is expected.

Tuesday night into Wednesday a stronger wave will form along the baroclinic zone with a sfc low moving from the Colorado Rockies to the near Lake Huron by Wednesday afternoon. As this system pushes through the U.P. will be under the left entrance region of a 300mb jet along with a band of strong fgen at 850-700mb. A cross section from northern WI through the North Central U.P. shows strong sloping fgen between 850-700mb with deep saturation, strong lift and negative EPV within the saturated layer hinting at CSI banding. One thing to note is that the strongest lift falls below the DGZ, which combined with warmer profiles will keep snow ratios lower, 10:1 to 12:1 expected. There is also a warm nose that pushes into the southern part of the U.P. introducing mixed precipitation types ranging from freezing rain in the far southern areas of the U.P. with a transition to sleet and then snow as you go north.

While there remains disagreement among guidance with the exact placement of the heaviest snow the REFS probabilities for 6"+ has come up to near 100% over the higher elevations of Marquette County which will also see lake enhancement with east to northeast winds. Slightly lower probabilities near the lakeshore and the central part of the county of 70-80%. The axis of 70-80% probabilities extends back to the southwest through Baraga to eastern Gogebic county. As far a 8"+ Marquette County (higher elevations) has the greatest potential. NBM probabilities for 6"+ in 24hr are lower, in the 30- 40% range over the high terrain of Marquette County.

As far as impacts, heavy snow rates Tuesday night into Wednesday morning combined with wetter, dense snow could make travel difficult even if amounts are higher end advisory. Have gone with a Winter Storm Watch for Marquette County as confidence for heavier snow is highest in this area, additional winter weather headlines are likely as the forecast evolves.

Snow tapers off through the day on Wednesday from west to east though it could linger a bit longer due to lake effect off of Lake Superior in the eastern half of the U.P. before finally tapering off in the evening as dry air works into the low levels and inversion heights fall.

The potential for hazardous winter weather (mainly snow) returns late Thursday into Friday and again over the weekend as two additional storm systems move through the Great Lakes.

AVIATION /18Z TAFS THROUGH 18Z TUESDAY/

Issued at 309 PM EDT Mon Mar 9 2026

Main aviation concerns on the 18Z TAF cycle are gusty winds this afternoon, potential for light snow/lower cigs late tonight/early Tuesday. Expect the gusty westerly winds to persist for the next few hours before quickly dying down late afternoon/early evening as they turn northerly to northeasterly. A band of light snow looks to develop over IWD/CMX late tonight (60-70% chance), with enough confidence to put in a period of prevailing IFR conditions. The band is more likely to break up before it reaches SAW, but retained PROB30 10-13Z for the smaller potential there. Cigs expected to fall to MVFR late tonight/early Tuesday morning, borderline IFR at IWD.

MARINE

Issued at 309 PM EDT Mon Mar 9 2026

A cold front will sink south across the lake tonight with northerly winds falling to less than 20kt behind the front. Low pressure will track through southern Lower Michigan Tuesday night into Wednesday bringing east-northeast winds strengthening to 25kt over the east half of the lake Tuesday night. A the low exits the region on Wednesday winds become northerly and increase to 30kt over the eastern half of the lake. The next storm system approaches the region on Thursday with southeast gales possible (40% chance), shifting north Thursday night before falling below 20kt on Saturday morning.

MQT WATCHES/WARNINGS/ADVISORIES

Upper Michigan... Winter Storm Watch from Tuesday evening through Wednesday afternoon for MIZ005.

Lake Superior... None. Lake Michigan... None.