Marine Weather and Tide Forecast for Stephenson, MI

DISCUSSION
Issued at 335 PM EDT Wed Jul 15 2026

Stout upper level high pressure continues to encompass much of the CONUS this afternoon, with Upper Michigan situated within northwesterly flow aloft on the periphery of this feature. GOES visible satellite and derived fire products highlight multiple large wildfires burning upstream from the Boundary Waters of northern MN to the Lake Nipigon region of northwest Ontario, with the associated smoke unfortunately focused directly on the UP given the northwest flow regime in place. Air quality sensors are reporting very unhealthy to hazardous conditions across the area as a result, and Michigan EGLE has thus extended the statewide Air Quality Alert through Thursday. The thick blanket of smoke has also wreaked havoc on the temperature forecast, with the Keweenaw and most of the eastern UP stuck in the 60s this afternoon while the rest of the area is mainly in the 70s aside from a few spots that have managed to reach the low to mid 80s across south-central.

The otherwise benign northwest flow pattern will persist through Thursday, and as such do not see much optimism for the smoke situation to dramatically improve over the next 24-36 hours. Hi-res smoke forecasts bear this out and in fact indicate a higher concentration of smoke in some instances on Thursday. Consider remaining indoors when possible and limiting strenuous outdoor activities for the next few days. The temperature forecast will continue to be tricky through at least tomorrow given the ongoing smoke concerns. Have opted to keep afternoon highs 5-10 degrees below NBM guidance across much of the area tomorrow, but that may not be enough and there is unusually low confidence in this forecast depending on how much smoke is overhead.

Friday at least offers the potential for some relief as upper level flow gradually pivots more zonal with the flattening of the upper level ridge by strong troughing over northern Quebec and Labrador.
This will open the door to an approaching shortwave trough which looks likely to bring at least some measurable rain across the area between late Thursday night and early Saturday morning. NBM still depicts a 60-80% chance for a wetting rain of at least a quarter inch across most of the area save for Menominee County through Saturday morning. This, coupled with a shift in the surface flow to a more southerly direction, will hopefully help to start to mix the smoke out of the lower levels of the atmosphere and even more importantly will hopefully have an effect on the upstream wildfires to limit smoke production going forward. Confidence on how that scenario will unfold remains low at this time given lingering questions about track, strength and timing of this system.

Aside from lingering questions about smoke, the forecast otherwise looks relatively benign through much of next week as the region settles back into northwesterly flow with temperatures near seasonal norms.

AVIATION /00Z TAFS THROUGH 00Z THURSDAY/
Issued at 707 PM EDT Wed Jul 15 2026

IFR to LIFR conditions are expected to continue over the terminals throughout the period as wildfire smoke from northern Ontario and the Boundary Waters continues to funnel into the region. With the air at the sfc becoming more stable during the overnight hours, we may see additional smoke accumulate near the sfc tonight. Thus, while we should expect vis to generally be around a mile, there could be drops down close to half mile to potentially even airport mins tonight. Expect conditions on Thursday to be nearly just as bad to potentially even slightly worse than today, as the HRRR smoke model shows an even greater coverage and density of wildfire smoke near the sfc across the U.P. While winds calm tonight, expect them to be light from the N/NE on Thursday with some Lake Superior lake breeze help.

MARINE
Issued at 335 PM EDT Wed Jul 15 2026

Will maintain Dense Smoke Advisories over all of Lake Superior and northern Lake Michigan/Bay of Green Bay through at least Thursday morning as wildfire smoke from Ontario and MN continues to drift over the region. Expect visibility to fluctuate below 1 nm at times.
There is a high likelihood that these headlines will need to be extended further out in time in upcoming forecast cycles given latest model guidance. Otherwise, winds remain below 20 kt today through Thursday as surface high pressure remains over Lake Superior. Winds may increase near/above 20 kt at times Friday through the weekend with a series of systems moving through, also bringing a potential for thunderstorms.

MQT WATCHES/WARNINGS/ADVISORIES
Upper Michigan...
None.
Lake Superior...
Dense Smoke Advisory until 11 AM EDT /10 AM CDT/ Thursday for LSZ162-240>251-263>267.

Lake Michigan...
Dense Smoke Advisory until 11 AM EDT Thursday for LMZ221-248- 250.