textproduct: Marquette

KEY MESSAGES

- Breezy today, especially along the Keweenaw and near Lake Superior. Northwest gales to around 35 knots are expected over central/eastern Lake Superior into tonight.

- A Winter Weather Advisory remains in effect for Luce County through Monday morning. An additional 1-3 inches of snow is expected, heaviest tonight. Moderate to heavy snowfall rates in conjunction with gusty winds could make travel difficult along the M- 28 corridor for end-of-weekend travel and for the Monday morning commute.

- High pressure brings quieter weather for most of this week with highs above freezing and lows below freezing.

DISCUSSION

Issued at 232 PM EST Sun Nov 16 2025

Afternoon RAP analysis shows deep low pressure over the Gulf of Maine, with sprawling surface high pressure over the Plains. In between, the Great Lakes remains under chilly NW flow with 850mb temperatures at around -8 to -10C. Surface temperatures over Superior hover at around 7-8C, resulting in delta-T certainly steep enough to keep the lake effect going in the NW wind snow belts. However, we're combating dry midlevel air over the region (as evidenced both in water vapor imagery and in observed and model soundings), so lake effect continues mostly over the far eastern portions of the UP given a longer fetch over the water. Even then, soundings remain quite dry, with just a few thousand feet of moisture within an elevated DGZ, very dry air just above it, and an inverted-V below the DGZ. Satellite and radar are showing LES over Alger, Schoolcraft, and Luce counties turning more cellular compared to the one or two dominant banding structures favored by much of the hi-res guidance. Perhaps this is due to the aforementioned dry air, or gusty winds and more breaks in the clouds lending some turbulence and somewhat better destabilization. With that, light snow totals below an inch are expected across our eastern zones the rest of the daytime hours.

As we head into tonight, guidance still hangs onto the potential for a couple of more dominant bands to extend into the eastern UP, perhaps with some Lake Nipigon connection. HREF also continues to indicate around a 20-30% chance for snowfall rates in excess of 1in/hr in Luce county late tonight into the early hours of Monday. Though additional snow totals across the eastern UP are only expected to top out in the 1-3in range, will hold onto the Winter Weather Advisory in Luce county given the potential for some travel impacts into early Monday morning. Lake effect snow then is expected to diminish throughout the day Monday as dry air intrudes and ridging aloft/surface high pressure encroaches on the UP. Additional light snow accumulations below an inch will be possible in the eastern UP.

Meanwhile, we continue to watch lake clouds erode across the western half of the UP with the dry airmass working in. Temperatures are rising into the mid 30s across most of the UP, but where skies are clearing, it wouldn't be a surprise to see some spots climb into the upper 30s under our weak November sun. Winds remain gusty as well, with 25-30mph gusts common especially across the eastern UP. Stronger gusts up to 40mph will be possible nearer to the Superior shoreline. Expect winds to gradually diminish overnight, though some 20-25mph gusts will still be possible over the Keweenaw and the shorelines into early Monday. As skies clear and winds in the interior UP turn lighter, temperatures may be able to turn rather chilly, bottoming out in the lower/mid 20s while to the east temperatures peak in the upper 20s to near 30. After rebounding into the 30s to near 40F Monday afternoon, temperatures turn even colder Monday night. Expect lows in the 20s for most, and possible into the teens in the interior-central UP.

For Tuesday, the closed low currently over Nevada is expected to progress through the Plains and eventually the Lower Midwest. This will be too far south for much, if any impacts across the UP, with just a slight chance for some rain/snow showers to graze our WI border zones. Uncontested ridging then takes hold, giving quiet weather for the Wednesday period. For the Thursday-Friday timeframe, models begin to diverge as they try and get a handle on a trough that is currently just off the Pacific NW. Latest deterministic guidance favors, in some form, the trough splitting into a closed Four Corners low and a Canada/US border-riding shortwave that may or may not eventually phase, or for a more simple textbook Colorado Low- type setup. Ensemble members also show quite a bit of spread. Additionally, shortwaves in the vicinity of the Hudson Bay could further complicate the forecast. Therefore, confidence in the details of the forecast into next weekend is low. For now, highly impactful weather is not expected outside of an ensemble outlier or two, though given the sheer number of potential features, a wetter pattern is expected around that period. For this week, expect highs above freezing (mid 30s to low 40s), and lows below freezing (20s to low 30s).

AVIATION /18Z TAFS THROUGH 18Z TUESDAY/

Issued at 557 PM EST Sun Nov 16 2025

VFR conditions are expected to continue across the terminals the rest of tonight through Monday. While some gusty winds may be seen at CMX tonight, expect the winds to die down over there by Monday afternoon. SCT to occasionally BKN lake effect cloud cover with low- end VFR cigs looks to continue over CMX and SAW until Monday afternoon as well; ridging moves in and brings clearing skies (and lighter winds) by Monday afternoon.

MARINE

Issued at 448 AM EST Sun Nov 16 2025

Northwesterly gales continue across eastern Lake Superior this morning as cold air aloft brings down gusts to 35-40 kt down to the surface. Long duration winds along the long NW/SE fetch of Lake Superior will support significant wave heights of 12-14 ft from Caribou Island to Pictured Rocks National Lakeshore, with waves across the central lake around 10 ft and around 4 ft in the west. Winds will fall below gales tonight, below 25 kt Monday morning, and below 20 kt Monday evening. Waves will similarly fall with time, with waves falling below 8 ft Monday morning and below 4 ft by late Monday night. With high pressure expected for much of the next week, winds look to remain below 20 kt. Late in the week into the weekend, a complex weather setup may support a low pressure passing through the Great Lakes. Confidence is low in the details, but there is a 10- 20% chance that a low pressure feature could be accompanied by gale- force gusts.

MQT WATCHES/WARNINGS/ADVISORIES

Upper Michigan... Winter Weather Advisory until 7 AM EST Monday for MIZ007.

Lake Superior... Gale Warning until 10 PM EST this evening for LSZ249>251-266- 267.

Lake Michigan... None.