Marine Weather and Tide Forecast for Frankfort, MI

DISCUSSION
Issued at 228 AM EDT Sat Apr 11 2026

Pattern Synopsis:

Surface high pressure over the IA / MN region will move overhead tonight, leading to subsidence overhead and clearing skies. This precedes a return to much more active conditions as longwave troughing sets up shop in the west, while a robust ridge makes its presence known across the southeast CONUS and into the Mid Atlantic.
Between these two features, a pronounced thermal gradient will drive robust southern stream jet maxima from the southern Plains, through the heart of the Corn Belt, and into the upper Great Lakes region.
This will allow for deep Gulf moisture to advect north and east through the aforementioned regions, overlapping periods of instability as well. Result will be an active period of weather to close out the weekend through at least the middle of next week...
featuring milder temperatures, but with the cost being rounds of showers and thunderstorms, some of which may be severe... and rainfall may exacerbate ongoing hydro concerns across the region.

Details:

Other than chilly weather tonight, not much to chat about for the rest of tonight and even into today / Saturday... lows bottoming out in the 20s for most, perhaps some teens in the interior by daybreak.
With surface high pressure overhead, anticipating sunshine to prevail as highs top out a few degrees above normal for early April... Highs in the mid-upper 40s north / lakeshores, 50s to near 60 across the rest of northern lower (warmest where snowpack remains minimal).

The first episode of active weather manifests Saturday night as the first plume of deeper moisture surges into the Lakes from the south and west. This may take some time to come about as preceding dry air aloft will have to be resaturated in order to drive stratiform rainfalls, as instability aloft will likely be suppressed to our south / west into Wisconsin and southern lower Michigan courtesy of a strengthening low level jet. As such, anticipating most areas to see periods of rain building later Saturday night through Sunday, with some embedded thunderstorms (especially in the SW parts of the CWA)
By Sunday afternoon, plentiful moisture should be overhead
1.00"+ PWATs, representing a 250 to 350 percent anomaly from the climatological normal, which for mid April is pushing a 4 sigma anomaly (very significant). What this means is that if a low level jet intrusion can develop again and actually force thunderstorms over the region Sunday afternoon into Sunday night, rainfall could be quite torrential. Not impossible for some areas to see 2.00"+ of rain by Monday morning... but where that happens remains up for grabs right now.

We get in between waves by Monday, with somewhat of a break, perhaps some showers to start the day. Another wave barges through the region Monday night into Tuesday, bringing another round of rain and thunderstorms. This particular wave is already showing up on SPC's radar, with portions of northern Michigan remaining included in the latest Day 4 convective outlook (15% chances across the SW CWA).
This particular wave will come with yet another statistically significant moisture intrusion (3 to 3.5 sigma anomaly PWATs, values in excess of 1.00"), and thus will pose the risk of more heavy rainfall across the region. Additional waves will traverse the region through the end of the week, and will deliver more rain to the region.

Coupling this with surface temperatures poking into the 50s-60s (perhaps 70s at times south), along with dewpoints well into the 50s, AND where there is an existing snowpack, will have to watch closely for significant runoff into prone areas of eastern upper and far northern lower Michigan. With the potential for the rapid eradication of lingering snowpack and the ongoing situation across Emmet, Cheboygan, and Presque Isle counties surrounding the Cheboygan River watershed, have elected to extend the ongoing flood watch in eastern upper to include the three aforementioned and most vulnerable counties in northern lower Michigan.

AVIATION /18Z TAFS THROUGH 18Z SUNDAY/
Issued at 126 PM EDT Sat Apr 11 2026

Cloud cover will increase later this evening from west to east ahead of the next rain chances for the region. Some embedded thunderstorms and moderate to heavy showers are likely beginning tonight lasting into Sunday night. As a result, MVFR to IFR cigs/vsbys will develop later tonight around 08z spreading west to east through the period. Onshore lake breezes develop near the coastlines this afternoon and turn more southeasterly tonight while increasing around 06z with gusts 20-25 knots common across terminals. LLWS is possible by the end of the period.

APX WATCHES/WARNINGS/ADVISORIES
MI...Flood Watch from 8 PM EDT this evening through Wednesday morning for MIZ016>018-086>088-095-096.
MARINE...None.