textproduct: Marquette

KEY MESSAGES

- Lake effect snow showers continue over the north wind snow belts through Friday night as a couple more disturbances pass through the region.

- Lingering moderate snowfall rates and patchy blowing snow could produce localized visibility reductions across the Keweenaw and also Alger County into this evening.

- Very cold in the east again tonight into Friday morning, with wind chills as low as -25F.

- Temperatures finally return to around normal this weekend, continuing through much of next week.

DISCUSSION

Issued at 345 PM EST Thu Jan 29 2026

The upper level pattern this afternoon is dominated by an elongated 500 mb trough with an axis extending from the Canadian maritime provinces across the Upper Great Lakes and into central Manitoba, maintaining a northerly lake effect snow regime over Upper Michigan today. A weak surface trough is analyzed over the eastern half of Lake Superior, which has been helping to maintain a dominant convergence band which had been parked over the western extent of Alger County for much of the day but has now showed signs of weakening as it shifts back into the eastern half of the county. Radar and satellite imagery reveal a somewhat complex lake effect scenario taking shape this afternoon, with influences from ongoing but weakening convergence, fairly strong land breezes, and the presence of multiple mesolows. A new NW-SE oriented band has also formed offshore of eastern Marquette County and extends into western Alger County. Have tentatively left the ongoing winter headlines in place through 7 PM this evening as HREF depicts most of the heavier snowfall rates remaining offshore. However, will have to closely watch radar and satellite trends through this evening as the southward progression of the trough eventually brings some of this activity onshore later this evening as depicted by various hi-res models. May need to consider some short fused headline extensions or special weather statements for lakeshore adjacent parts of Alger and Marquette Counties as any of the radar features currently noted offshore may be capable of producing an hour or two of localized moderate snowfall and significant visibility reductions should they make their way onshore this evening.

Aside from the ongoing lake effect snow concerns, the eastern UP will be in for another night of temperatures in the negative teens and wind chills in the -20 to -25F range as northerly flow maintains cold air drainage out of NE Ontario. Impacted areas will be slightly expanded from last night, with the latest Cold Weather Advisory in effect for Luce, Schoolcraft, Alger, and Delta Counties through Friday morning. Temperatures will warm back into the teens across the area during the day on Friday, with warmer overnight lows then expected for Friday night as temperatures mainly stay in the single digits above zero across the east. Otherwise, troughing maintains a mainly light lake effect regime in the northerly wind snow belts through Friday night, with an additional 1-2 inches expected for most areas adjacent to Lake Superior and perhaps slightly more for parts of Alger County and Keweenaw.

Will finally start to see some more noteworthy changes in the pattern by this weekend as the upper level trough drops south of the region and allows positively tilted upper level ridging to build into the Upper Great Lakes from the west. This will mostly bring an end to lake effect this weekend, with daytime temperatures rebounding closer to or even slightly above normal highs in the 20s for the first time in several weeks. Another weak trough may bring some light snow early next week, but high pressure should generally help to keep lake effect at bay through much of next week as delta- Ts only get into the teens at times. Expect high temperatures to generally remain in the 20s, with overnight lows in the single digits above to the low teens through much of next week.

AVIATION /00Z TAFS THROUGH 00Z SATURDAY/

Issued at 727 PM EST Thu Jan 29 2026

Lake effect SHSN pattern continues through the daytime hours of Friday, though not all sites will see snow continuously. SAW will begin the period with no SHSN but a band of snowfall is moving onshore at 00Z and may impact the terminal by 01Z, bringing a brief period of lowered visibility with it. IWD and CMX are already experiencing -SHSN at 00Z which is causing IFR to LIFR conditions. IWD in particular is over 30 percent likely to see prolonged periods of LIFR conditions overnight tonight, with CMX about 20 percent likely. With support for SHSN weakening somewhat Friday as chances of precipitation fall to the 30s percent range at all sites in the afternoon, expect mainly MVFR conditions during the daytime hours at all sites. Expect winds primarily out of the north and northwest throughout this TAF period with winds mainly around 5 kt gusting to 10 kt early, though gusts pick up to 20+ kt by the afternoon of Friday.

MARINE

Issued at 345 PM EST Thu Jan 29 2026

A passing upper level trough will maintain northerly winds of 20-25 kt and 3-6 ft wave heights over Lake Superior through Friday night, resulting in small craft headlines in the nearshores and ongoing heavy freezing spray concerns through early Saturday morning. Conditions will improve as high pressure builds overhead this weekend, allowing winds to diminish below 20 kt across the lake. Winds increase to 20-25 kt again out of the southwest on Sunday ahead of the next trough, then shifting northwesterly in its wake through early next week. Do not expect any gales as probabilities remain low through the period.

MQT WATCHES/WARNINGS/ADVISORIES

Upper Michigan... Cold Weather Advisory until 10 AM EST Friday for MIZ006-007- 013-014-085.

Lake Superior... Heavy Freezing Spray Warning until 7 AM EST /6 AM CST/ Friday for LSZ240>242-263.

Heavy Freezing Spray Warning until 1 AM EST Saturday for LSZ243-244-249-250-264-266.

Heavy Freezing Spray Warning from 1 AM Friday to 1 AM EST Saturday for LSZ245>248-265.

Lake Michigan... None.