Marine Weather and Tide Forecast for Cheboygan, MI

SHORT TERM /THROUGH TONIGHT/
Issued at 333 AM EDT Sat Jun 21 2025

An ongoing MCS treking across the upper Midwest is expected to continue tracking eastward this morning, with indications that at least parts of eastern Upper and northwest Lower will be impacted as the system rides a tightening instability gradients into the area. There remains enough support from upstream trends and the environment downstream for the complex to strengthen and hold together to bring the potential for damaging winds, large hail, and a low end tornado threat as it moves through.
Confidence continues to increase in at least some severe risk during the morning to early afternoon hours.

As the system exits, partial clearing and continued strong southwesterly flow ushering in deep moisture may allow the environment to recover as we head into the afternoon/ evening hours to support additional thunderstorms. Forecast soundings show strong instability and sufficient deep layer shear to support additional storm development, especially along lingering boundaries. If storms redevelop, they may again become strong to severe with all threats still possible.

Temperatures will rise into the 90s across the region combined with dewpoints in the upper 60s to low 70s, making heat indices rise into the upper 90s/ low 100s. Slightly cooler conditions can be expected near the lakes and where cloud cover lingers, though it will still be uncomfortably hot and humid region-wide.
A very warm and humid night follows, with lows holding mostly in the 70s across much of the region allowing little relief from the heat. A stray shower or storm is possible overnight (mainly across eastern Upper), but most of the area should stay quiet.
As of now, heat advisories go into effect at noon today and continue through 8 PM Sunday.

LONG TERM /SUNDAY THROUGH FRIDAY/
Issued at 333 AM EDT Sat Jun 21 2025

Hot and humid conditions will continue into Sunday and Monday under persistent upper-level ridging. Highs both days will climb into the 90s for most areas, with dewpoints in the upper 60s/ 70s pushing heat indices into the 95-100 (105?) range. Overnight lows will stay in the 70s as well, again, offering little relief from the heat... Heat advisories remain in effect through Sunday evening, with the growing possibility of it being extended into Monday (timing of potential precipitation could play a role in how high temperatures get on any given day).

A transition toward a more active pattern begins late Monday into Tuesday as the ridge breaks down and a frontal boundary stalls near the region. This boundary will remain a focus for showers and thunderstorms through much of the upcoming week.
Multiple disturbances look to ride along the front, bringing several rounds of showers/ storms with the potential for strong storms and possible heavy rainfall if we experience any training storms. Precipitation chances will heavily depend on how the boundary sets up and evolves through the week.

Temperatures trend back toward more seasonable levels mid to late week, with highs returning to the 70s and low 80s. Humidity looks like it could keep things slightly muggy with the unsettled pattern likely to persist through the end of the period.

AVIATION /18Z TAFS THROUGH 18Z SUNDAY/
Issued at 1257 PM EDT Sat Jun 21 2025

VFR conditions will gradually return to all terminals this afternoon/evening as the lower clouds dissipate. A few additional showers and storms remain possible through tonight, most likely at PLN, CIU. In these areas, conditions could briefly drop to IFR/MVFR. Patchy fog will be possible later tonight, especially at PLN, CIU. Gusty south/southwest winds into early this evening with some gusts over 30kt possible.
Winds will gradually diminish tonight.

APX WATCHES/WARNINGS/ADVISORIES
MI...Heat Advisory until 8 PM EDT Sunday for MIZ016>018-020>036-041- 042-099.
Air Quality Alert from 8 AM Sunday to midnight EDT Sunday night for MIZ016-020-021-025-026-031-099.
Beach Hazards Statement through Sunday evening for MIZ020-025- 031-095-096-098.
MARINE...Small Craft Advisory until 8 PM EDT Sunday for LHZ345-349.
Small Craft Advisory until 8 PM EDT Sunday for LMZ323-341-342- 344>346.
Small Craft Advisory until 8 PM EDT this evening for LSZ321- 322.