textproduct: Marquette

KEY MESSAGES

- A wintry mix is possible Wednesday morning before temperatures warm well above freezing in the afternoon. There is the potential (40-70% chance) for a glaze of ice on surfaces to start the day, mainly in the western half of the U.P.

- Southerly gales to 40 knots are expected over the east-central open lake and along the nearshores of Marquette and Alger counties on Wednesday.

- Active weather resumes this weekend. Rain will be the dominant precipitation type, which in combination with a prolonged period of above freezing temperatures and dewpoints could result in river rises.

DISCUSSION

Issued at 200 PM EDT Tue Apr 7 2026

Nice, pleasant early Spring weather is being realized across the U.P. this afternoon as the crest of high pressure ridging departs from the area to the east as a Clipper simultaneously traverses east along the U.S./Canada border the rest of today through Wednesday. While mostly sunny skies and warm air advection are being realized overhead, with remnant cold air associated with the previous low taking its time leaving the area, highs this afternoon are expected to still be below normal (i.e. generally in the 30s save maybe the lower 40s in the far west and south central). In addition to the sunny skies, RHs are dropping to around 30% as of early this afternoon across much of the interior area; could see the RHs drop down into the 20 percents before the sun sets this evening as very dry air remains behind the high pressure ridging.

As we move into the overnight hours, expect clouds to return from the west late as the warm front of the Clipper approaches. While isentropic lift along the front is not that impressive, it should be enough to kick-off some wintry precipitation late tonight/early Wednesday morning over the western half. With sfc temperatures in the pre-dawn to just a few hours post-dawn expected to be at or below freezing, thinking we could see snow, sleet, and freezing rain across the west and central Wednesday morning. While the impacts from sleet and snow look to be fairly low (since only up to a half inch could be seen), should freezing rain be the more dominant precipitation type there could be some travel impacts to the Wednesday morning commute as a glaze to just under a tenth of an inch of ice could be seen; as of now, the NBM has limited a glaze of ice chances to around 30%, whereas the HREF currently has a widespread 40 to 70% chance across Upper Michigan. While I don't believe the HREF percentages over the eastern U.P. as much, thinking the dry air aloft and marginal forcing/temperatures over the central and west are more conducive to ice chances. Therefore, should the freezing rain chances associated with the HREF be realized along the warm front late tonight into Wednesday morning, the mid shift may need to issue a SPS to highlight the hazardous travel conditions for the Wednesday morning commute. As temperatures warm throughout the morning thanks to the warm air advection behind the front and the increasing sunshine, expect a potential transition over to rainfall, especially over the eastern U.P. where the front doesn't look to arrive until later Wednesday morning; any sleet/snowfall/ice that we receive during the early morning hours Wednesday looks to melt by Wednesday afternoon as above normal high temperatures in the mid-40s to mid-50s look to return. The warmer temperatures will also bring back some gradual snowmelt across the area, which in turn will slowly increase river rises across the region. In the warm sector of the low, a LLJ looks to mix down to the sfc over the south-wind downslopes near Lake Superior. Looking at the 12z RRFS, we may see a few southerly gusts up to 45 mph at times Wednesday afternoon. While confidence is too low to issue one at this time, a Wind Advisory may need to issued for Marquette and Alger counties in the future to account for the strong southerly winds during the day Wednesday. As the cold front of the Clipper moves through late in the day, expect the liquid in the rain showers to add to the SWE lost during the daylight hours to the river rises. Thankfully, temperatures generally cooling back down to around or below freezing Wednesday night should somewhat limit the river rises as snowmelt slows down or ceases for a few hours.

Generally quiet and warmer weather is expected to end the week as fairly zonal flow on Thursday and Friday give way to ridging by Saturday. That being said, there is a small (30% or less) chance that some snow and rain could be seen near Menominee Thursday night into Friday morning as a shortwave low passes through the Mid- Mississippi Valley. With highs continuing to get above freezing each day across the area (i.e. the 40s and 50s), expect a slow snowmelt as dewpoints are projected to remain below freezing. This in turn will lead to only slow river rises, which should limit flooding concerns for the rest of this week.

The big event for this forecast period looks to come in early next week as a robust low pressure system develops off of the northern Rockies. The warm front of the low is looking to move through sometime around Saturday night, with the warm sector of the low looking to remain overhead Sunday through Monday. Because of this, abundant Gulf moisture is looking to surge northwards over us and bring warm and moist conditions to the area early next week; dewpoints as of now are projected to be well above freezing, potentially even getting into the 50s while highs reach into the 50s, 60s, and potentially lower 70s near the Wisconsin border. With this synoptic setup making it easy for gusty winds from a potential LLJ to reach the sfc and with PWATs looking to get to 1.25 inches or higher, we may see increasing snowmelt across the region in conjunction with heavy rain showers and thunderstorms. This could accelerate river rises across the area, which in turn would heighten flood concerns. While this is still several days out, we will continue to monitor this situation as it evolves.

AVIATION /18Z TAFS THROUGH 18Z WEDNESDAY/

Issued at 200 PM EDT Tue Apr 7 2026

Clear sky VFR conditions prevail at all sites into tonight with most sites staying under 10 kt as high pressure remains overhead. The next system approaches late tonight into Wed morning as mixed winter precipitation spreads into the terminals from west to east 10-12z, along with LLWS and southerly surface winds gusting to 25-30 kt. This will yield primarily MVFR conditions at all terminals through the end of the period, with intermittent IFR cigs and vis possible at times in heavier precipitation. Expect mixed precip to transition to rain at most sites as temperatures warm above freezing 14-16z Wed.

MARINE

Issued at 200 PM EDT Tue Apr 7 2026

Winds of around 20 knots or less this afternoon increase from the south tonight to 20 to 30 knots across the lake as a warm front begins to push in from the west late; expect a wintry mix of light snow/sleet/freezing rain/rain along the front. Behind the passage of the warm front, expect gales up to 40 knots in the nearshores by Marquette and Alger counties and in the east-central open waters on Wednesday; expect the winds to decrease to 20 knots or less over the western half of the lake by Wednesday afternoon as the cold front pushes through, bringing rain showers with it. The eastern half also drops down to 20 knots or less for a couple of hours behind the cold front Wednesday evening. However, with some cold air advection seen behind the cold front late Wednesday night, expect winds to increase from the west to 25 to 30 knots late Wednesday night into Thursday morning across the lake, with a few gale force gusts up to 35 knots possible (up to a 20% chance, highest along and just east of the north-side of the Keweenaw). With zonal flow setting up shop overhead for the latter part of the workweek, expect the winds to gradually dwindle on Thursday, eventually becoming 20 knots or less across Lake Superior by Thursday evening. The light winds look to remain for the rest of the week as high pressure ridging moves through on Saturday. However, as the warm front of a low dropping out of the northern Rockies moves through on Saturday night, expect winds to increase from the south to 20 to 30 knots. The strong winds look to continue through the day Sunday as the warm sector of the low remains overhead.

MQT WATCHES/WARNINGS/ADVISORIES

Upper Michigan... None. Lake Superior... Gale Watch from Wednesday morning through late Wednesday night for LSZ249-250-266-267.

Lake Michigan... Gale Watch from Wednesday afternoon through late Wednesday night for LMZ221-248-250.