textproduct: Marquette

KEY MESSAGES

- Isolated/scattered light lake effect rain/drizzle is possible over mainly the eastern U.P. tonight into Monday morning. Expect rainfall accumulations to be not much more than a trace.

- Breezy conditions continue into this evening near Lake Superior, with northwest winds gusting to 20-30 mph in the Keweenaw and from Marquette eastward. Winds diminish overnight into Monday morning.

- Could see some light rain showers mainly over the eastern U.P. Tuesday through Wednesday as well as gusty winds once again over the Keweenaw and eastern U.P.

DISCUSSION

Issued at 409 PM EDT Sun Oct 4 2026

Visible satellite shows clearing skies across much of Upper Michigan this afternoon as drier air works into the region behind a departing clipper low now located near the southern tip of James Bay per latest RAP analysis. Breezy northwest winds continue in a cold air advection regime in the wake of the low, with gales over the eastern half of Lake Superior and winds gusting to 25-35 mph over adjacent land areas and in the Keweenaw. A reinforcing shot of cold air will arrive over Lake Superior tonight as the upper trough deepens over eastern Canada, sending 850 mb temps below 0 C. As a result, could see some light lake effect rain showers redevelop over the eastern extent of the UP tonight into early Monday as lake surface temperatures continue to reside around 13-15 C in the east. With surface temps falling into the low to mid 30s in a few spots overnight, can't rule out seeing the first snowflakes of the season mixing in for inland areas in the east, with no accumulation. In terms of rainfall, do not expect much if any measurable precipitation from these showers through Monday. Otherwise, Monday is shaping up to be a pleasant fall day with plenty of sunshine over most of the area and temps holding in the 50s to perhaps low 60s near the WI border.

Another weak disturbance will approach the area Monday night into Tuesday ahead of the next trough dropping out of central Canada. A relative lack of forcing and plenty of mid level dry air to overcome per model soundings will serve to limit rain chances to 20-30% for now. Once again can't rule out a few snowflakes mixing in with rain Monday night, this time in the interior west, but meager QPF values of a few hundredths of an inch will serve to limit any meaningful precipitation. Temperatures then rebound into the 60s across the area on Tuesday amidst low level southerly flow. Cold advection then quickly returns Tuesday night into Wednesday in the wake of the system, kicking off another round of potential lake effect rain showers and breezy conditions during the middle of the week. Surface ridging then favors drier weather later in the week before another low then potentially brings additional rainfall chances to the area next weekend.

AVIATION /00Z TAFS THROUGH 00Z TUESDAY/

Issued at 825 PM EDT Sun Oct 4 2026

VFR conditions have returned to all TAF sites and will continue for duration of TAF period. Any lake effect rain showers/drizzle should stay east of TAF sites tonight and not impactful. Meanwhile, breezy west/northwest winds will persist into tonight at CMX with gusts still in the 25 to 30 kt range. Elsewhere, northwesterly sustained wind speeds up to 12 kts will continue through this evening at SAW before tapering off.

MARINE

Issued at 409 PM EDT Sun Oct 4 2026

Lake Superior: Northwesterly gales continue over the eastern half of Lake Superior into this evening as a low departs into Quebec. Thereafter, expect a slow general decrease tonight into Monday morning, with winds dropping to 20 kts or less across the lake by Monday afternoon as high pressure moves overhead late Monday. On an aside, there is a threat for some sporadic waterspouts over the southeastern lake this evening into late tonight before the waterspout threat diminishes early Monday morning. Don't expect the calmer conditions to last all that long, as another low from Canada digs towards the Upper Great Lakes on Tuesday. Therefore, expect winds to once again pick up from the south throughout the day across Lake Superior, reaching speeds of 20 to 30 kts over the entire lake with a few gale force gusts up to 35 kts possible over the eastern lake. As the cold sector of the low moves in Tuesday night into Wednesday, expect the winds to weaken slightly to 20 to 30 kts from the west Tuesday night before having a slight uptick from the northwest on Wednesday (gale chances around 20 to 40% in the cold sector on Wednesday, highest over the eastern lake). As sfc ridging slowly returns for the latter portion of the work week, expect the winds to progressively weaken with time Wednesday night through Thursday, eventually dropping to 20 kts or less again by Thursday night.

Northern Green Bay and northwestern Lake Michigan: Winds have veered westerly today and will gradually turn northwesterly through this evening. While reinforcing CAA from Canada will keep northwest winds at 15 to 20 kt tonight, expect incoming high pressure to return calmer winds of 15 kts or less to the area by late Monday. Don't expect the calmer winds to last all that long as another low from Canada approaches the Upper Great Lakes on Tuesday. This low is projected to increase winds from the south and southwest throughout the pre-dawn and daytime hours, with gusts of 30 kts to potentially even gales of 35 kts (up to 40% chance) possible by the afternoon hours. Once the cold sector of the low starts to come into the region by Tuesday evening though, expect the winds to die down closer to 15 kts while veering with time. However, another subtle shot of CAA could bring west to northwest winds of 15 to 20 kts back over the region on Wednesday before dropping down to 15 kts or less again by Wednesday evening as high pressure ridging begins to approach from the west. While west-northwest winds may gust up to 15 to 20 kts once again during the day on Thursday, expect calmer winds of 15 kts or less again come Thursday night.

MQT WATCHES/WARNINGS/ADVISORIES

Upper Michigan... None. Lake Superior... Gale Warning until 11 PM EDT this evening for LSZ248>251- 265>267.

Lake Michigan... None.