textproduct: Marquette

KEY MESSAGES

- Light to moderate snowfall continues, ending in the early afternoon. Additional snowfall up to 1 inch, with wind gusts up to 30 mph creating blustery conditions for Easter morning festivities.

- Another round of light to moderate snowfall tonight through Monday brings 1-3 inches of snow to the northern and western UP, with some locations between Ironwood and Ontonagon (as well as the rural high terrain of Baraga and Marquette Counties) reaching 4-6 inches. Banded snowfall could create highly variable road conditions and catch holiday travelers off-guard.

- Dry weather Tuesday before active weather resumes for the back half of the week into the weekend. Rain will be the dominant precipitation type, which in combination of highs above freezing could cause some rivers to continue to slowly rise.

DISCUSSION

Issued at 402 AM EDT Sun Apr 5 2026

Early morning GOES-East water vapor imagery and RAP analysis show a mature, vertically stacked low moving north and east of Lake Superior, with the dry slot fully east of the region and wraparound moisture evident over the UP. This moisture, weak dynamic forcing, orographic enhancement, and 850mb temperatures around -10C are supporting weak banded snowfall this morning. With low level winds roughly out of the northwest, the high terrain along the spine of the Keweenaw down to Ironwood as well as the rural highlands of Baraga and Marquette Counties will see the most accumulation with this with chances of over 1" of new snowfall around 50 percent by 12Z. However, with cold advection aloft and the departure of the synoptic forcing, the snowfall will quickly wrap up, and precip should wrap up by 18Z. The pressure gradient is still fairly tight between the wake of the low and the broad high pressure over the Plains, with around a 15mb pressure gradient from Michipicoten, ON and Duluth, MN at 07Z. This will drive some wind gusts near 30 mph this morning, which may make for some blustery conditions for any Easter morning festivities. However, this afternoon should see some breaks in the clouds, so any outdoor pictures with the Easter Bunny could have some sun.

Tonight, showers return to the region as a weak shortwave rotates around the upper trough over Hudson Bay. Model guidance struggles to resolve a distinct surface low with this, but a surface trough is evident on global deterministic guidance. Cool air surging in with the background cool northwesterly flow will give the showers a lake enhancement boost, and then with winds becoming pure northerly in the wake of the surface trough on Monday, pure lake effect snow showers are forecast. Once again, the higher snow totals look to impact the high terrain along the spine of the Keweenaw as well as Baraga and Marquette Counties north/east of US-41, where locally 4-6 inches of snow are possible, with the remainder of the western UP and Lake Superior counties seeing 1-3 inches by 00Z Tuesday. However, some CAMs are more aggressive with snowfall than others, so given the spread, will elect to wait for at least one more round of hi res guidance before issuing a Winter Weather Advisory. While snow totals wont be extreme (chances of Winter Storm-level snowfall is 10% or less), occasional moderate-to- heavy snow showers in banded form will make travel conditions (visibility and road slickness) highly variable over short to medium distances, which could catch Easter holiday travelers off guard.

Stout high pressure to near 1035 mb then establishes itself over the Upper Great Lakes Tuesday, bringing the driest day of the forecast period to the region (from a "chance of precipitation" perspective). This kicks off a warming trend in the high temperatures, with most of the UP breaking freezing on Tuesday and the proceeding days seeing many high temps in the 40s.

The break in active weather is brief. A closed low that is currently spinning over Bethel, Alaska will pivot through the Canadian Rockies by Tuesday afternoon, becoming positioned just upstream of the Upper Great Lakes by Wednesday afternoon. This system is expected to bring some Pacific moisture as well as establish at least a weak Gulf connection as it passes, providing ample moisture for rain to occur. The Euro ensemble shows two low clusters by 15Z Wednesday, one over the Sioux Falls, SD region and another straddling the North Dakota/Canada border. These low clusters then combine north of Lake Superior by 06Z Thursday. Rain totals by Thursday morning look to be in the quarter inch (30-60% chance) to half inch (up to 20%) range. Uncertainty then grows significantly as spread increases drastically, however the general pattern looks to continue to be rainy, including conditions over the Southeast to Southern Plains being more conducive to advect more Gulf moisture to the Upper Midwest. Attention will turn quickly to hydrology in this period as the snowpack has not only persisted, but has retained much of the liquid precipitation (freezing rain and rain) of recent as well as being reinforced by the recent (and will be reinforced by upcoming) wet snow/sleet. Should warm and moist southerly winds help snowmelt in addition to heavy rain occur (CPC highlights a moderate risk for heavy rain around the 12th-13th), flooding will be a concern, though spread is so high at this point that any details will be muddy at best. For now, just something to monitor in the outlook.

AVIATION /18Z TAFS THROUGH 18Z MONDAY/

Issued at 140 PM EDT Sun Apr 5 2026

VFR conditions prevail for the moment as local ridging and high pressure have cleared out skies nicely across all three terminals this afternoon. These conditions last into the early evening, however, an upstream shortwave dives south tonight, returning scattered snow showers and MVFR/IFR to the west after 00z. given the scattered nature of expected snow showers tonight, have gone with prob30 groups through ~12z tomorrow for periodic IFR drops in vis/cigs. Stronger cold air advection ramps up tomorrow morning, bringing more persistent snow showers and IFR conditions at all terminals, aided by lake and orographic enhancement. Diminishing winds tonight ramp up to 15-25 kts after 12z tomorrow, particularly at CMX/SAW.

MARINE

Issued at 402 AM EDT Sun Apr 5 2026

A departing low pressure system will leave a brief northwesterly gale of around 35 knots over east-central Lake Superior this morning, falling below 30 kt by early afternoon and below 20 kt by this evening. Waves will briefly build to as high as 12 ft near Grand Island this morning (8-11 ft elsewhere in the east half) before quickly falling below 8 ft this evening and below 4 ft tonight. Another weak disturbance brings wind gusts near 30 kt from the north on Monday, though chances of gales are only 25% or less. This will drive waves of 4-8 ft, and the cool northerly air will help create conditions supporting widespread moderate to locally heavy freezing spray. Winds fall below 20 kt early Tuesday morning with a high pressure expanding over the Upper Great Lakes, which will also decrease waves and freezing spray. The next chances for gales are Wednesday and Wednesday night, when a low pressure passing north of the lake bring up to 30% chances of gales, though if those gales occur, there is a 1 in 3 chance that those gales could be in excess of 40 kt. Uncertainty then grows considerably, though the weather pattern remains active.

MQT WATCHES/WARNINGS/ADVISORIES

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