Marine Weather and Tide Forecast for Sault Ste. Marie, MI

DISCUSSION
Issued at 1229 AM EDT Mon Apr 20 2026

In wake of a deep trough moving east across New England, a tranquil, dry, and seasonably cool day is expected today as sfc high pressure builds overhead. Quick moving trough across Quebec tonight will keep any precipitation threat to the north of the region. Little shortwave will combine with some instability to the south of northern MI to produce some showers/storms, meanwhile, temperatures recover quite quickly on Tuesday as southwesterly winds usher in 50s and 60s. Expect another mild and dry day on Wednesday as ridging builds to our west across the Upper Midwest and Plains states.

Warmest day of the week will likely be Thursday, as ridging over the Plains moves eastward over the Great Lakes in response to magnificent energy and subsequent low pressure system across the central portions of the Nation. Expect temperatures to soar into the 60s and 70s across many inland locales as a warm front extending from the low pressure system pushes northward (presumably to ~the Bridge). Additionally, southerly to southwest flow will overspread northern MI, with a band of above normal PWs and dewpoints expected on Friday, and thus, showers and thunderstorms possible. Several runs of deterministic guidance support at least a threat for moderate to locally heavy rainfall, with NBM prob guidance low to medium-ish for >0.50" of rain.

Looks like northern MI might be in limbo next weekend as robust troughing swings to our west, and east, with ridging in-between. I suppose all it takes is a little perturbation in the flow to keep us unsettled. Temps appear to be closer to seasonable during this time.

HYDROLOGY
Issued at 1229 AM EDT Mon Apr 20 2026

Despite water levels and flows continuing to decrease, the saturated soils across northern MI keep the flooding threat across localized low lying areas that have recently experienced river or lake flooding. Portions of Indian River and the Little Sturgeon River in Indian River continue to exhibit areal flooding via NWS Meteorologists. Similarly, National Water Model Flood Inundation Mapping services suggest inundated houses along the Black River and Black Lake, and likely across Wolverine as well (again, some of this is the fact that the water is having a poor time draining from these locations). Nevertheless, conditions should continue to improve for most locations across the board with a several day stretch of dry weather this week. HEFS guidance, along with current, extrapolated hydrographs, show all major river systems with a downward trend through this week, with perhaps only portions of the Manistee River lingering with minor flooding. Next shot at rain will be Friday, with the potential for moderate to locally heavy rainfall. Worth keeping an eye on, especially with the sensitive areas, although one would assume some drying of the soils will take place given the warmer temperatures.

AVIATION /00Z TAFS THROUGH 00Z TUESDAY/
Issued at 1152 PM EDT Sun Apr 19 2026

VFR. Chilly but increasingly dry air is over northern MI. Lake effect clouds and SHSN will diminish heading into tonight.
VFR conditions thru the TAF period, though mid/high clouds will increase into Monday evening.

Winds lighten into tonight. Southerly breezes later Monday.


APX WATCHES/WARNINGS/ADVISORIES
MI...None.
MARINE...Small Craft Advisory until 5 AM EDT early this morning for LHZ345>349.
Small Craft Advisory until 5 AM EDT early this morning for LMZ323-341-342-344>346.
Small Craft Advisory until 5 AM EDT early this morning for LSZ321-322.