textproduct: Marquette

KEY MESSAGES

- Longer period of lake effect snow showers and near normal temperatures Wednesday through early this weekend. Accumulating snow for the north to north-east wind snowbelts is becoming increasingly likely.

DISCUSSION

Issued at 228 PM EST Mon Nov 9 2026

Afternoon GOES satellite imagery reveals a low amplitude shortwave digging through northern MN with it's main isentropic ascent region occurring across the UP. Thus far, the moisture starved shortwave hasn't been able to produce anything other than cloud cover. Can't rule out a few sprinkles across the northern tier of the UP this afternoon, but no measurable precip has been added to the forecast. Temps in the 40s to low 50s fall back to the 30s to near 40, warmest lakeshores. The shortwave kicks east through Ontario tonight, veering breezy winds to the NW through Tuesday and keeping dry conditions in place with similar temps expected.

The more impactful forecast challenge presents itself during the mid- to-late week through early this weekend. A shortwave slides south of the UP early wednesday, touching off light rain across the UP. At the same time, troughing in eastern Canada retrogrades through Quebec and eastern Ontario, sending a parade of additional shortwaves across the Upper Great Lakes while spilling cold air aloft across the region. 850 mb temps late Wednesday begin to fall below -5C and hover between -7 to -11C over a ~+8C Lake Superior sfc temp, inducing lake effect snow showers across the N to NNE wind snowbelts across the region through at least early Saturday. There remains some uncertainty surrounding where the highest snowfall totals will setup as models struggle to agreed on moisture characteristics in the sfc layer and within the DGZ, as well as the placement of seeder-feeder / convergence dominant bands. As per usual with the first lake effect snow events of the year where temperatures near the immediate lakeshores are warm, modified by onshore flow off the lake, the high terrain of Baraga/Marquette counties will likely see the greatest snow totals by Saturday morning. Local research tools investigating low level lapse rates to determine snowfall accumulation potential near the immediate lakeshores suggest snow will struggle to stick. Wouldn't surprise me to see some light snow <0.5" in Marquette/Munising proper, but it may be contingent on wet-bulb processes and if a dominant band can find its way there. Latest ensembles suggest a 40-70% chance for at least 4" of snow in the Michigamme Highlands between ~Negaunee to Herman. Elsewhere, a trace to 2" is likely, but there are some signals of localized higher amounts in dominant band structures in connection with upstream Lake Nipigon and eastern lake induced troughing. These features will be fickle and hard to place until more CAM guidance can sus out QPF bullseyes over the next 24-36 hours. NBM probability for at least 1" of snow parks between 50-90% for select areas of the Keweenaw high terrain as well as the Porkies/Gogebic range. Otherwise temps return near normal with highs in the 30s to low 40s and lows in the 20s to low 30s.

AVIATION /18Z TAFS THROUGH 18Z TUESDAY/

Issued at 1226 PM EST Mon Nov 9 2026

The current cloud cover is expected to move out of the area by late this evening, with clearing starting at IWD this afternoon and ending at SAW around 8pm tonight. Even with cloud cover, ceilings will be high enough for VFR conditions at all terminals throughout the TAF period. Winds are expected to shift from southwesterly to westerly overnight, becoming west-northwesterly by noon on Tuesday. A strengthening lower-level jet over the eastern U.P. indicates a moderate chance (~50%) for LLWS at KSAW around 07-09 UTC. LLWS is also possible for IWD and CMX at this time, however, confidence is much lower (~30% chance), so LLWS was not included in the TAFs for these terminals.

MARINE

Issued at 228 PM EST Mon Nov 9 2026

Lake Superior: A clipper system tracking just north of the lake tonight into Tuesday increases southerly winds to 15 kts with gusts to 20 kts late afternoon ahead of a cold front. Winds turn west behind the cold front this evening between 15-20 kts with gusts 20- 30 kts into Tuesday morning, strongest over the east half of the lake. Winds fall below 20 kts by Tuesday night as weak high pressure returns. From there a tightening pressure gradient and cold air moving over the lake supports a longer period of north to northeast winds 15-20 kts with gusts up to 30 kts Wednesday night into Friday. Winds taper off for the weekend with high pressure moving over the Western Great Lakes.

Northern Lake Michigan and northern Bay of Green Bay: Wind gusts remain at or below 20 kts through Wednesday. Late this week brings gustier north-northeast winds up to 20-25 kts with the tighter pressure gradient and cold air moving overhead. Winds taper off this weekend with high pressure moving over the Western Great Lakes.

MQT WATCHES/WARNINGS/ADVISORIES

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