textproduct: Marquette

KEY MESSAGES

- Daily chances for precipitation are expected throughout the week into early next week. Thunderstorms will be possible at times, but severe weather is not expected.

- Temperatures remain below normal this week into next week.

DISCUSSION

Issued at 1228 PM EDT Mon Jun 15 2026

Showers and a couple of thunderstorms spreading into the U.P. this afternoon from Lake Superior this afternoon as a subtle shortwave continues to dig down into the Upper Midwest. While the SPC analysis page shows some instability ahead of the convection, with very little shearing in the atmosphere, no severe weather is expected. While most spots today could see up to at least a few sprinkles, some areas could 'win out' rainfall-wise and see over a quarter inch; the REFS run has a 40% chance of some areas seeing over a quarter inch by this evening. Otherwise, outside of the shortwave today, breezy westerly winds could gust up to 25 mph at times this afternoon over the U.P., with up to 30 mph winds possible in the Keweenaw. In addition, expect temperatures closer to normal this afternoon, with highs getting into the lower 70s across most of the area.

Expect the troughing pattern to hold steady overhead the rest of this week, keeping cool and drier interior Canadian air over the U.P. as shortwave lows cycle down from Alberta into the region nearly every day. Thus, expect below normal temperatures to continue through the rest of this week as highs range from the 60s to the lower 70s. In addition, the constant shortwave action will allow showers and thunderstorms to return nearly every day, although rain chances may last all day some days whereas others may be relegated to the afternoon hours in order for the convection to get some diurnal heating help. Still keeping an eye on a more impressive Clipper low moving through the Northern Plains and Upper Midwest during the middle of this week; while the low's center is currently projected to miss us to our south, we could see some wrap-around moisture go north of the low and bring a stratiform-like rain pattern over us. The rainfall amounts from this could be wetting (0.10 to 0.25 inches) across most of the area, with the latest LREF showing a 50 to 90% chance of seeing over a quarter inch of rainfall across the area Wednesday and Wednesday night (highest in the south central, which is closest to the low's track).

While the troughing pattern may lift a tad as we head into next week, below normal temperatures do appear to persist, with another Clipper low from Alberta potentially impacting the U.P. once again near the end of the forecast period.

AVIATION /12Z TAFS THROUGH 12Z TUESDAY/

Issued at 713 AM EDT Mon Jun 15 2026

VFR prevails for most of the forecast period, though MVFR conditions will be possible in any showers and thunderstorms that move through at IWD and SAW later today. Will continue to highlight that impact with PROB30 groups. Otherwise, ceilings may lower to MVFR at IWD early Tuesday morning. Westerly winds will increase at CMX, with wind gusts in the 25 to 30 kt range through this evening.

MARINE

Issued at 1228 PM EDT Mon Jun 15 2026

WSW winds of 20 to 30 knots early this afternoon drop back down to 20 knots or less by this evening after the shortwave bringing showers to the lake moves through the area. While an isolated t- storm or two is possible this afternoon into this evening, it isn't expected as not as much instability will be found over Lake Superior as compared to the surrounding land areas.

Expect the light winds of 20 knots to continue until late Wednesday when a strong Clipper low approaches the Great Lakes region from the Northern Plains. As the low approaches, expect winds to increase from the east, picking up 20 to 25 knots Wednesday night before becoming northerly at 25 to 30 knots over the eastern lake Thursday morning; the latest NBM shows up to around a 40% chance for low-end gales over the eastern lake near the U.P. on Thursday. Expect the winds to back to the northwest on Thursday, lightening up to around 20 to 25 knots over the eastern half of the lake by the evening hours. The northwest winds of 20 to 25 knots look to continue through the overnight hours and Friday, potentially backing to the west. Expect the winds to slacken further to 20 knots or less Friday night, remaining light through the rest of the weekend as the troughing pattern overhead begins to breakdown.

MQT WATCHES/WARNINGS/ADVISORIES

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