textproduct: Marquette

KEY MESSAGES

- Well above normal temperatures continue into the work week.

- Spotty rain and snow showers graze the northern and eastern UP tonight into Monday morning; some patchy freezing drizzle or freezing rain is possible in the far eastern UP.

- Confidence is growing that an impactful winter storm will move into the Great Lakes region Tuesday night through at least Wednesday. Potential impacts include heavy snow, strong winds, and possible mixed precipitation, depending on the track and strength of the system.

DISCUSSION

Issued at 353 PM EST Sun Feb 15 2026

Afternoon water vapor and RAP analysis show a weak shortwave trough exiting eastward this afternoon, with weak ridging and drier midlevel air in place over the UP. This has translated to sunny and quiet conditions over much of the area, with temperatures soaring into the lower to mid 40s over the central and western UP. However, visible satellite reveals quite nicely widespread low cloud cover over Superior that has spilled over the Keweenaw and into the eastern UP. Surface obs and webcams also indicate patchy fog here and there, most dense over the Keweenaw - perhaps with some helpful upsloping? In these cloudy areas, temperatures have only been able to reach as high as the lower/mid 30s.

Heading into tonight, expect increasing midlevel cloud cover as yet another weak shortwave, currently over southern Saskatchewan, slides over or just north of Lake Superior. Most of the CAMs continue to keep the majority of the precipitation over the lake, and given the weak forcing as well as rather dry air over the UP, this is reasonable. Still, some spotty precipitation won't be ruled out late tonight through Monday morning as the associated cold front moves through, mainly over the northern tier counties with just sprinkles/flurries over the southern half of the UP. Model soundings support mainly rain/snow showers, though a warm nose present over the far east presents a potential for some freezing drizzle/freezing rain Monday morning. Still, with very light QPF, significant impacts are not expected. Precipitation wraps up by Monday afternoon, while temperatures rise from lows in the upper 20s/lower 30s to highs in the upper 30s and lower 40s.

Significant pattern change is still on track for the middle of next week as deep troughing invades the western CONUS and a very strong southwesterly jet develops from the Desert Southwest to the Upper Midwest. Lead wave ejecting across the Plains Tuesday night/Wednesday will be the main focus here. Strong and fairly long- duration overrunning WAA is forecast over the local area as this wave goes very negatively tilted, shears out, and stalls (in the multi-model mean). We'll have healthy deep moisture to work with as PWATs increase to near three quarters of an inch given your model of choice, as high as 300% of normal! Much of the deterministic and ensemble guidance paints us with a widespread 0.6-0.8in of QPF by 00Z Thursday, with higher totals up to an inch where lake and terrain enhancement occur (namely, the north-central UP and our counties surrounding the Bay of Green Bay).

However, crucial differences still exist that will determine precipitation type and amount. Most global models and their AI/Ensemble counterparts are working towards the GEFS/GFS solution, with surface low pressure closing off near NW IA Tuesday evening, deepening to near/below 990mb over southeastern MN, and tracking into central or northern WI by Wednesday evening. This places the heaviest snowfall axis over the UP and northern MN. The Euro ENS and deterministic remain the more northerly outlier, with the axis of heavier snow away to our northwest, mainly impacting the Arrowhead of MN. For us, this solution would provide the least snow compared to other guidance, and most p-type issue potential across the southern portions of the CWA. Regardless of correct model solution, overrunning scenarios like this tend to under do WAA, mixed precip, and freezing rain accumulations. Will note that GFS soundings, in spite of being the "snowier" solution, still support mixed precipitation of a least some variety over much of the UP. This is all to say that exact totals remain uncertain, but what we do know: shovel-able wet, heavy snow and mixed precipitation that may include freezing rain is becoming likely for the midweek period, generally Tuesday night through Wednesday. Additionally, given the forecast pressure gradient, gusty E to NE winds with wet winter precip type will add an extra layer of hazard to the equation.

Respite from winter weather may be short lived (only 24-36 hours) as guidance suggests a secondary CO low lifting into the Great Lakes early Friday. As of now, both deterministic and ensemble models are quicker to lift this one through the area and suggests less overall QPF than this first system. Additionally, overall track and system strength are not fully agreed upon. A more wintry airmass in place behind this next feature will keep in chances for lingering lake effect into next weekend while temperatures trend towards more or less seasonable values.

AVIATION /18Z TAFS THROUGH 18Z MONDAY/

Issued at 1256 PM EST Sun Feb 15 2026

With light winds and stubborn low level moisture, FG/BR and low stratus will continue flight restrictions at CMX and return at SAW in the next hour or two. A bit of vis improvement at CMX is anticipated, but guidance is all over the place on timing. Opted to keep a VLIFR tempo until 20Z, but confidence is low. SAW is on the edge of a low stratus deck creeping west into Marquette County. This should eventually overrun SAW, dropping cigs to IFR/LIFR. FG development at SAW is not anticipated until this evening/tonight when IFR/LIFR is favored. Also tonight, a round of rain/snow showers is possible at CMX. IWD should remain VFR until late in the period post cold front.

MARINE

Issued at 254 PM EST Sun Feb 15 2026

Winds remain below 20 kts Monday through at least Tuesday morning before winds pick up ahead of our next system. Forecast models continue to show potential for a significant system to bring strong easterly winds Tuesday night into Wednesday, with up to 90% chance for gales and 25-40% chance for storms. Winds are likely to be elevated around 30 kt behind this system for the end of next week as colder air returns.

MQT WATCHES/WARNINGS/ADVISORIES

Upper Michigan... None. Lake Superior... Gale Watch from Tuesday afternoon through Wednesday evening for LSZ162.

Gale Watch from late Tuesday night through late Wednesday night for LSZ242>250-263>266.

Gale Watch from Wednesday morning through Wednesday evening for LSZ251-267.

Lake Michigan... None.