textproduct: Marquette

KEY MESSAGES

- Well above normal temperatures expected this weekend. Highs into the 80s are possible over the western UP today and Sunday.

- A Red Flag Warning is in effect for Ontonagon and Gogebic Counties today into Sunday. Elevated fire weather conditions are also likely elsewhere across the U.P. today and Sunday.

- Chances for widespread rain showers with light accumulations late Monday afternoon into Tuesday morning.

-Temperatures return to near-normal Tuesday.

DISCUSSION

Issued at 250 AM EDT Sat Oct 10 2026

Early morning water vapor imagery and RAP analysis feature compact midlevel troughing digging into the Pacific Northwest and British Columbia, spinning up a surface low that is currently analyzed over Saskatchewan. Broader troughing is present over the mouth of the St. Lawrence, with ridging in between over the Great Lakes. At the lower levels, sprawling surface high pressure is centered over New York State, setting up a tight pressure gradient and strengthening southerly flow closer to home ahead of the aforementioned Clipper low. Resulting WAA has helped to lead to an increase in midlevel cloud cover over the UP, and nighttime microphysics also shows some upper level cloud cover streaming in from the upstream system. However, the back edge of this cloud deck is already moving into northern WI, so we should expect a return to sunny skies after daybreak. Temperatures hover in the mid and upper 40s for most, but range in the lower to mid 50s in the far west; temperatures should either hold steady or rise slightly the rest of the night.

The Clipper low continues to move through the Canadian Prairie and into Ontario through the morning and early afternoon, but with dry air in place and better forcing to our north, we can expect dry weather to persist. What impacts we will feel will be gusty winds, with an ever-increasing pressure gradient and good mixing allowing us to tap into the strengthening LLJ aloft. Most areas could see gusts up to 30mph, while areas prone to downsloping could see some gusts upwards of 40mph. Highs are expected to reach the low 80s (15-30 degrees higher than normal) in the western U.P. while the east will remain in the mid-70s due to the moderation of temperature as winds move across the relatively cool surface of Lake Michigan. Afternoon RHs are expected to fall to around 35-40% in the western U.P., with some spots falling even further to near 30%. Meanwhile, RH remains in the 50s for the east. Under these conditions, elevated to critical weather conditions are expected for the western U.P. this afternoon; a Red Flag Warning remains in effect for the far western UP, though gusty winds and persistent dryness will continue to lead to elevated wildfire concerns across the entirety of the UP.

Warm temperatures, gusty winds, and low RHs continue into Sunday. Highs will return to the low 80s in the west (mid 70s in the east) Sunday afternoon, while RHs fall into mid-30s for most (mid-40s in the east). Wind speeds are expected to decrease to 15-25mph heading into Sunday afternoon as the surface pressure gradient from Saturday weakens. Clear skies are expected until Sunday evening. Heading into the work week, the ridging pattern aloft flattens out somewhat under the influence of troughing over northern Ontario. At the surface, troughing associated with a frontal system is expected to move across the area. This system will bring chances for precipitation Monday afternoon through Tuesday morning. Showers are expected to be widespread but with low accumulations, with a ~50% chance for precipitation totals to exceed 0.1 inches by Tuesday morning at any given location. Higher accumulations are possible along the lakeshore as northerly winds behind the cold front allow for the possibility of lake enhancement. The passage of the remnants of Isaias through the eastern CONUS this weekend introduces some uncertainty in the models for next week. Currently, upper-level ridging is expected to return for the midweek, bringing back seasonable temperatures and light winds before a troughing pattern looks to move through Thursday evening.

AVIATION /18Z TAFS THROUGH 18Z SUNDAY/

Issued at 116 PM EDT Sat Oct 10 2026

VFR conditions continue through the TAF period. A Low-Level Jet is expected to develop across the U.P. this evening as an inversion forms and the boundary layer decouples. Strong LLWS up to 40-45kts at 2000ft is expected at all terminals from 00z tonight into 14z Sunday morning as a result of the strengthening LLJ.

MARINE

Issued at 250 AM EDT Sat Oct 10 2026

Lake Superior: Winds are increasing out of the southeast early this morning, with gusts up to 20-25kts already becoming common over much of the eastern and central lake. Winds continue to increase into the daytime hours while veering more southerly; 35-40kt gales are possible in east-central Lake Superior this afternoon into tonight. Over the western arm, winds will be southeasterly at 15-20kts. Waves will be 4-8ft (highest offshore) in the east and 2-3ft in the west. Sunday afternoon, winds lighten to 10kts and shift southwesterly over the western arm while winds remain at 15-20kts and southerly in the east. Waves will be 1-3ft. Monday morning, winds shift northeasterly and increase up to 30kts with wave heights building to 5-7ft in the afternoon. Some isolated gales are possible in the western arm. Tuesday, wind speeds decrease to 15-20kts but remain northerly with wave heights from 3 to 5ft. Winds look to decrease further into the midweek period.

Northern Green Bay and northwestern Lake Michigan: Winds are increasing out of the southeast early this morning, with gusts to 20kts already becoming common. Winds increase further to 25-30kts this afternoon, and some gale-force gusts are not out of the question on the Lake Michigan side. Waves will be 2-3ft in the bay, 4-8ft in northern Lake Michigan. Southerly winds decrease to around 20kts into Sunday morning. Wave heights remain at 2-3ft for the bay, 3-5ft over northern Lake Michigan. Winds continue to decrease through Sunday night, reaching 10-15kts by Monday morning with 0-2ft waves. Monday afternoon, winds shift to northerly and increase up to 20kts as a cold front moves through the area. Tuesday, northerly winds continue at ~15kts with 2-3ft waves.

MQT WATCHES/WARNINGS/ADVISORIES

Upper Michigan... Red Flag Warning until 6 PM EDT /5 PM CDT/ Sunday for MIZ002- 009.

Lake Superior... Gale Warning until 2 AM EDT Sunday for LSZ248>251-266.

Lake Michigan... None.