textproduct: Marquette

KEY MESSAGES

- Highs in the 90s are possible near the stateline this afternoon.

- Thunderstorm chances (15-30%) persist in the forecast (far south) this afternoon into this evening.

- Dry weather still on track to return on Wednesday, likely persisting into the weekend.

DISCUSSION

Issued at 322 PM EDT Tue May 26 2026

This afternoon, temperatures in the south and interior west are reaching into the low 80s, on track to reach high 80s and low 90s due to ongoing westerly WAA and strong solar radiation. This heat may be mitigated in areas affected by a Superior lake breeze: 0.5- degree base reflectivity shows a clear boundary moving onshore in a line centered roughly at Harvey beginning at 1340Z and moving to the southwest and inland. This bow-shaped breeze reached Gwinn at 1440Z, and stretched to a line spanning from Michigamme to Bark River by 1730Z. Behind the lake-breeze head, temperatures inland sit at least 10F below those ahead of it in the high 60s and low 70s; temperatures along the lakeshore, well within the marine envelope, are even chillier in the 50s and low 60s.

Winds this evening will lighten into the night, as the region continues to sit under westerly mid-level zonal flow and ill- defined, sprawling high surface pressure. Along with the clear skies thus far today, strong mixing, and dry air in place in the low- levels, relative humidity values are plunging to between 20-30% in the interior west. Though RH values are not quite as low in the eastern UP at the time of this writing, they are expected to bottom out in the high 20% to low 30% range later this evening (around 22Z). Due to the synoptic subsidence and consequent light winds, however, fire weather danger is expected to remain only borderline elevated in some areas for the rest of today.

Some potential for convection and precipitation exists over Menominee County and the southern UP between 18Z and 00Z, as an MCV brushes the WI state border, then is steered east-southeasterly overnight. The 1630Z issuance of SPC's Convective Outlook upgraded the western border of Menominee County from general thunderstorms to a marginal severe risk. The HRRR and NAM show some elevated CAPE, but guidance agrees on unimpressive shear across the board. With this in mind, thunderstorms are likely for Menominee County tonight, with precipitation chances reaching only up to 50% and for a only a few hours tonight.

High pressure and warm temperatures persist until the weekend as an omega block forms over the northern Great Plains and southern Canada. Regionally, westerly mid-level zonal flow gives way to northwesterly veering to northerly flow by Wednesday midday as surface high pressure organizes and drops southward toward the Great Lakes. On the surface, winds remains light as the center of this high tracks directly through our CWA on Thursday. Expect high temperatures in the 80s in the interior and south and 70s elsewhere (lower along the lakeshores) through the week. A similar pattern is expected Friday through Sunday as the omega block persists through the weekend, with warm daytime highs, well above-freezing lows, and light winds.

So far, the warmest day looks to be Friday (after today), with highs interior west reaching into the high 80's. With minimum RH's forecast to be between 30-50%, apparent temperature tops out in the mid-80s (70s and lower east and near the lakeshores). The warm weather may increase heat risk concerns for some of the more vulnerable portions of the population; be sure to drink plenty of water, and don't overwork yourself outside, especially during the hottest hours of the day.

AVIATION /00Z TAFS THROUGH 00Z THURSDAY/

Issued at 733 PM EDT Tue May 26 2026

Radar and satellite imagery depict a broken line of thunderstorms across northern WI as of 00z Wed, but this activity will stay well south of the state line this evening and yield VFR conditions under mostly clear skies across Upper Michigan. Building surface high pressure maintains these conditions for the duration of the TAF period. A weak disturbance swinging through the area tonight may bring a few high based showers, but abundant dry air in the low levels will likely keep any precipitation from reaching the surface. Expect light wind to become northerly and increase to around 10 kt at the terminals on Wed, potentially gusting to 20-25 kt at KSAW by late Wed afternoon.

MARINE

Issued at 322 PM EDT Tue May 26 2026

Light winds of generally 20 knots or less continue through this afternoon through tonight as sfc high pressure moves through the region. With a cold front descending over the area late tonight into Wednesday morning, we may see some thunderstorms over the western lake; that being said, thunderstorm chances at this time remain very low, at less than 15% currently. Nevertheless, chances may increase throughout the overnight hours as additional CAMs are picking up on potential convection over northern Wisconsin, the U.P., and/or western Lake Superior.

Behind the cold front, expect funneling of northeast winds over the western lake to increase the winds speeds to 20 to 25 knots, with the eastern lake potentially gusting over 20 knots late in the day too. That being said, with a high pressure block setting up shop over the Central U.S. from the middle of this week onwards, expect winds to remain light at 20 knots or less throughout the rest of this week and this weekend. The one exception may be on Saturday when a shot of cold air descends over the lake from the north; winds may increase to 20 to 25 knots over the western lake from the northeast before dying down in the evening.

MQT WATCHES/WARNINGS/ADVISORIES

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