textproduct: Marquette

KEY MESSAGES

- Chilly this morning with frost in the interior west. A Frost Advisory is in effect until 9AM EDT for several counties in the western UP. Patchy frost is possible elsewhere across the interior central and east.

- Widespread rain moves into the UP from west to east late today through Tuesday morning. There is a general 25-60% chance for rainfall amounts >0.5", with the highest chances across the southern half of the UP.

- Gale Watches have been upgraded to Gale Warnings over the Upper Great Lakes for tonight through Tuesday. Southerly gales 35-40 kts turn westerly by early Tuesday afternoon. Westerly gusts 40-45 kts will be common with a few gusts to 50 kts possible (up to 50% chance) near the Keweenaw Peninsula.

- Strong westerly winds are expected Tuesday within and near the Keweenaw where frequent gusts of 45+ mph are possible (60-90% chance).

- The strong winds over the Upper Great Lakes tonight through Tuesday are expected to create dangerous swimming conditions along the Schoolcraft and Alger County shorelines on Tuesday.

DISCUSSION

Issued at 147 AM EDT Mon Sep 14 2026

Incoming high pressure has led to the cessation of the lake effect rain showers over the east early this morning and has brought clear skies overhead. This, in addition to the antecedent cool air overhead, has allowed temperatures to drop down into the mid 30s in portions of the interior west as of midnight EDT this morning; expect this trend to continue as some spots potentially get into the 20s. These chilly early Fall low temperatures will create areas of frost tonight over the interior west. Thus, a Frost Advisory is in effect until 9AM EDT this morning for Gogebic, Ontonagon, southern Houghton, Baraga, Iron, and Dickinson counties. While not as widespread as the interior west early this morning, some patchy frost is also expected in portions of the interior central and east too, with some of the more sparsely populated areas of the interior east potentially seeing more widespread frost in spots; however, given that this area is heavily forested, generally not for ag. use, and again sparsely populated, decided to not hoist up a Frost Advisory for the southwestern interior portion of Alger County and northeastern portion of Delta County. After sunrise this morning though, expect the frost threat to dissipate as temperatures warm into the 60s by this afternoon.

Expect a somewhat quiet weather day today, although that changes come the mid-to-late afternoon hours as a warm front approaches the area. As the warm front approaches, expect winds from the south to pick up, with gusts up of 20 to 30 mph being seen over the interior areas and downslopes along Lake Superior by the early evening hours. In addition, rain showers with potentially a few rumbles of thunder thrown in there are expected to begin moving into the western U.P. late this afternoon/early this evening. Some of the rainfall could be heavy at times, although no flash flooding is expected due to the quick-hitting nature of the warm-becoming-occluding front tonight and the ongoing drought conditions. The latest HREF shows a general 25 to 60% chance that over half an inch of rain will fall over most of the U.P. between early this evening and Tuesday morning, with a near 0% chance around Marquette and a near 100% chance near Menominee. While this isn't quite looking to be the wetting rainfall that was hoped for yesterday morning, it does seem like it still may be able to bring some relief to the drought conditions being seen across much of the area.

While some gusty southerly winds of 25 to 40 mph could be seen across the area tonight with the occluding front passing through, expect a slight break in the winds before winds pick up from the west behind the front on Tuesday as CAA works through the area. While wind gusts look to be at about the same speeds or slightly weaker across most of the area on Tuesday, westerly wind gusts of 45+ mph are projected to occur over the Keweenaw during the late morning to early afternoon hours. With the LREF even showing a 60- 90% chance of wind gusts over 45 mph by early Tuesday afternoon over the Keweenaw, a Wind Advisory may be forthcoming for that portion of the Yoop. Some wind gusts around 45 mph or so could also be seen along portions of the lakeshore in the west and north central too, but given that the stronger winds aren't expected to make it inland, no Wind Advisory is expected for these areas as of the current going forecast. One more note about the winds: the high winds over the Great Lakes tonight through Tuesday is looking to bring dangerous swimming conditions back over the Lake Michigan beaches of Schoolcraft County through the entire day Tuesday and the Lake Superior beaches of Alger County for at least the afternoon hours. Therefore, it goes without saying this late in the season that swimmers should avoid putting themselves in such a dangerous situation and wait for a calmer day to take an early-Fall dip into our Great Lakes. As high pressure moves back into the region on Tuesday night, expect the winds to rapidly fall off and for the skies to become clear, allowing lows to fall into the 30s across portions of the interior; some patchy frost may be seen once again in the interior west Tuesday night.

Moving into the rest of the week, expect generally quieter weather as zonal flow in the upper levels and shortwave ridges moving through the U.P. generally keep active weather away. While this should keep temperatures fairly seasonable for the rest of the week, this does also support dry weather continuing until the end of the forecast period, provided we don't get grazed by a nearby shortwave.

AVIATION /12Z TAFS THROUGH 12Z TUESDAY/

Issued at 721 AM EDT Mon Sep 14 2026

VFR conditions and light winds prevail across Upper Michigan through this afternoon. An approaching system brings rain into KIWD and KCMX 20-00z and into the central UP including KSAW after 00z. This will be accompanied by a downward trend to MVFR conditions potentially some periods of IFR 00-06z Tue. A strong south-southwesterly LLJ will also bring low level wind shear concerns late in the period as winds at FL020 increase to 50+ knots be latest model soundings. Rain ends from west to east after 06Z, but MVFR ceilings linger the rest of the night.

MARINE

Issued at 147 AM EDT Mon Sep 14 2026

Lake Superior: Light winds of 20 knots or less early this morning give way to increasing southeast and eventually south winds late this afternoon, with gales of 35 to 40 knots being seen over the eastern lake by this evening while winds of 20 to occasionally a few gale force gusts up to 35 knots are seen over the west half. As the approaching warm front responsible occludes overhead and continues through the area tonight through Tuesday morning, expect some showers with a few rumbles of thunder to move through the lake. While winds could die-down for a few hours once the occluding front passes, expect them to reinvigorate to gales of 35 to 45 knots on Tuesday from west to east; some storm force gusts up to 50 knots will be possible over the central lake near the Keweenaw late Tuesday morning through early Tuesday afternoon, with the latest LREF showing up to a 50% chance of this occurring. However, because of the quick-hitting nature of the frontal system, expect weakening high pressure to build back in Tuesday night into Wednesday, with winds rapidly dying down to 20 knots or less again by late Tuesday night and remaining that way potentially for the rest of the week.

Northern Green Bay and northwestern Lake Michigan: Light winds of 15 knots or less this morning give way to increasing southerly winds this afternoon, with southerly gales of 35 to potentially 40 knots being seen late tonight as an occluding front moves through the region. While some rumbles of thunder could be heard tonight, no severe weather is expected given the lack of energy aloft. Behind the front on Tuesday, expect the winds to slowly dwindle as they veer with time, eventually lightening up to 15 knots or less again by Tuesday evening. With weakening high pressure building in Tuesday night into the mid-week, expect the light winds to remain across the area for at least the rest of the workweek.

MQT WATCHES/WARNINGS/ADVISORIES

Upper Michigan... Frost Advisory until 9 AM EDT /8 AM CDT/ this morning for MIZ002-004-009>011-084.

Lake Superior... Gale Warning from 11 PM this evening to 8 AM EDT Tuesday for LSZ249.

Gale Warning from 7 AM EDT /6 AM CDT/ to 4 PM EDT /3 PM CDT/ Tuesday for LSZ162.

Gale Warning from 8 AM EDT /7 AM CDT/ to 5 PM EDT /4 PM CDT/ Tuesday for LSZ240.

Gale Warning from 8 AM EDT /7 AM CDT/ to 8 PM EDT /7 PM CDT/ Tuesday for LSZ241>243.

Gale Warning from 8 PM this evening to 8 PM EDT Tuesday for LSZ244-245-248-265-266.

Gale Warning from 10 AM to 8 PM EDT Tuesday for LSZ246-247.

Gale Warning from 2 AM to 8 PM EDT Tuesday for LSZ250.

Gale Warning from 3 AM to 9 AM EDT Tuesday for LSZ251-267.

Gale Warning from midnight tonight to 8 PM EDT Tuesday for LSZ263-264.

Lake Michigan... Gale Warning from 11 PM this evening to 8 AM EDT Tuesday for LMZ221-248-250.