Marine Weather and Tide Forecast for Muskegon Heights, MI

DISCUSSION
Issued at 308 AM EDT Fri Jun 13 2025

- A Few Showers Mainly South of I-96 Through Saturday

Elevated instability drops to almost nothing today, and as such we are only expecting a few showers to pop during the day as dew points recover to around 60F after falling this morning. With a general lack of synoptic forcing present, nothing very organized will develop with just hit and miss shower activity and many areas staying completely dry. A similar situation is in place late tonight into Saturday morning, with perhaps a better shot at showers near and south of I-94 before exiting out of the region Saturday afternoon

- Dry for Most Areas Sunday into Monday

The majority of medium range guidance keeps the region dry Sunday and Monday. A light lake breeze develops Sunday and the inland- moving lake modified air will interact with easterly surface flow and low 60s dew points to help generate some cumulus, but likely not any showers at this point. The ECMWF is indicating zero MUCAPE so that should help keep things in check. For Monday, there is a slight chance for some showers and perhaps a thunderstorm as a subtle 500 mb shortwave trough moves through and weak 850 mb winds may try to converge across WI / Lake Michigan and angle into the region. The ECMWF is the main model showing this scenario and as such POPs are not high at this time.

- Midweek pattern: Humid with Thunderstorms at Times

A noticeable uptick in humidity will occur Tuesday through Wednesday as dew points start knocking on the door of 70F. This occurs as a synoptic pattern change will be underway. Ensemble guidance is favoring a 500 mb trough and an enhanced mid level jet moving into the Midwest by Wednesday. A fairly strong upper level jet for mid June is forecast to move through at that time (90 to 100 knots). Equally important will be a much more dynamic low level jet moving in than we have seen recently, with 40-50 knots shown by the GFS, GEM, and ECMWF. There are just some timing differences at this point but good confidence on the existence of a solid LLJ mid week. Organized and potentially strong thunderstorms are possible during the midweek period, with early thoughts suggesting Wednesday may have the best potential. This is also supported by NSSL's machine learning severe weather probabilities and NCAR's AI NWP-based forecasts favoring the Great Lakes for some severe weather potential.

AVIATION /06Z TAFS THROUGH 06Z SATURDAY/
Issued at 125 AM EDT Fri Jun 13 2025

Thunderstorms earlier from GRR to LAN have diminished. Isolated showers and thunderstorms over Lake Michigan south of Holland have also diminished. However, with a gradient of elevated instability present overhead a weak surface boundary, can't rule out some showers popping up and impacting mainly MKG, GRR, and LAN until about 12z. Will keep thunderstorms out of the forecast but continuing monitoring trends across the region. After 00z Saturday, a broader area of light showers may move into southern Lower Michigan and with that precipitation comes lower ceilings potentially. Some ceilings may get below 2000 ft across our southern terminals and will need to keep an eye on IFR potential with sub-1000 ft cigs forecast to get close to the MI/IN border within the 00z-06z Saturday window.

MARINE
Issued at 308 AM EDT Fri Jun 13 2025

Waves generally 1 foot or less are expected through the weekend with offshore flow today into part of Saturday before some weak NNW flow takes over during the afternoon hours of Saturday and Sunday.
These winds are not expected to increase wave activity at this time but trends will be monitored.

GRR WATCHES/WARNINGS/ADVISORIES
MI...None.
MARINE...None.