Marine Weather and Tide Forecast for Port Washington, WI

UPDATE
Issued 535 AM CDT Tue Jul 28 2026

Forecast is on track this morning. Low stratus have filled in across southern Wisconsin through the overnight as temperatures cool within a still moist low level air mass. 5-10 MPH winds have prevented the boundary layer from decoupling in most locations, which has held fog potential to nearly zero areawide.
Have seen a few reports of brief visibility reductions near the state line where low level moisture is a touch deeper, but nothing that will call for any headlines. Any patchy areas of fog will quickly diminish as the sun comes up.

Expecting a warm but not hot day today, with noticeably lower humidity compared to yesterday. Will see plenty of sun along with the warm temperatures, though it could be filtered at times as wildfire smoke from the Pacific Northwest attempts to move into the Upper Mississippi Valley. Expecting any low concentrations of smoke to remain in the mid-upper levels/well away from the surface, thus making air quality concerns low.

Quigley

SHORT TERM
Issued 1101 PM CDT Mon Jul 27 2026

Overnight through Wednesday:

The leading edge of the cold front is finally making it into southern WI late this evening as the weak surface low moves into lower Michigan. We can see a wind shift to the north, but temps and dewpoints are still elevated. Lows tonight will be in the 60s. There are a few low clouds out there (patchy stratus), and we cannot rule out some patchy fog once again.

The surface low will continue eastward Tuesday as an upper trough becomes a little more amplified over the Great Lakes.
That slight amplification will help increase the northerly winds over Lake Michigan and push the cooler and drier air from northern WI into southern WI by daybreak. A period of low clouds is expected just behind the front early Tuesday morning, but the dry air and mixing (with steady north-northeast winds) will quickly bring sunny skies for the rest of the day.

The Nighttime Microphysics IR composite satellite channel is showing some upwelling along the Wisconsin coastline of Lake Michigan. This should help enhance a lake breeze tomorrow and bring even cooler temps to the lakeshore in the afternoon. High temperatures will range from the low-mid 70s near the lakeshore to the lower-mid 80s inland. A pocket up upper 80s is expected in southwest WI. The biggest change will be the dewpoints. They got into the upper 70s today and they will only be around 60 Tuesday.

Visible satellite had a milky appearance behind this front when it was in northeast MN and Lake Superior this afternoon. The HRRR & RRFS Smoke models are showing fair amounts of vertically integrated smoke right behind the front in the morning, but then more diffuse values in the afternoon. The surface smoke forecast is much lower and nothing like the values we saw a week and a half ago.

Lows Tuesday night will be in the upper 50s to lower 60s under light winds and clear skies. Patchy fog is possible.

Cronce

LONG TERM
Issued 1101 PM CDT Mon Jul 27 2026

Thursday through Monday:

High pressure will begin to push east on Thursday, allowing for southwesterly sfc return flow over Wisconsin. While the lingering high should keep us dry through the day, surface dew points will modestly moisten into the mid to upper 60s, with afternoon highs again returning to the upper 80s.

Thursday night into Friday, low to mid level warm advection is expected ahead of an approaching elongated trough over the western Corn Belt. Showers and storms are expected on the leading edge of this warm advection, but deterministic runs of the ECMWF and GFS differ in the track of the trough and storms for the day on Friday. The GFS favors a more northerly track that would keep rain around for most of the day on Friday, while the ECMWF guidance favors a more southerly track that would bring us a glancing blow of rain in the morning, with drier conditions in the afternoon.
NBM PoPs somewhat favor the GFS solution at this time bringing likely PoPs (~60%) into our area Friday afternoon into Friday evening. Chance PoPs (30 to 45%) then linger into Saturday morning as the trough slowly pulls away to the east and south.

A sfc ridge will then build in behind the exiting trough, promoting dry conditions for Sunday and Monday. Temperatures Friday through Sunday will remain seasonable with highs in the low 80s. By the end of the extended period, it looks like another ridge from the plains leans east into Wisconsin, bringing warmer temperatures in the upper 80s to 90 on Tuesday.

CMiller

AVIATION
Issued 535 AM CDT Tue Jul 28 2026

Low stratus clouds linger through sunrise across most of southern Wisconsin with primarily MVFR CIGs . Have noted occasional IFR observations through the overnight hours in southeast Wisconsin, which have been accounted for in the 09/12Z forecasts at ENW and MKE. Winds have largely prevented FG development through the overnight, though sporadic VIS reductions have been reported closer to the Wisconsin-Illnois border. Have thus included TEMPO mentions of BR through 13Z at ENW. Both low CIG and VIS readings will quickly improve after sunrise. VFR flight categories prevail through the remainder of the period as high pressure moves across the western Great Lakes.

Quigley

MARINE
Issued 1101 PM CDT Mon Jul 27 2026

Low pressure around 29.5 inches over central Lake Michigan will move to the lower Great Lakes by Tuesday morning. The associated cold front will track southward across Lake Michigan tonight. T Northerly winds are expected to gust around 30 kt over central and southern Lake Michigan late tonight through Tuesday. Much lighter northerly winds are then expected late Tuesday night into Wednesday as high pressure around 30.0 inches builds into the northern Great Lakes. The high will maintain light winds for Thursday and Friday as well, but winds will take on a more southerly direction.

There is a Small Craft Advisory in effect for the nearshore zone of southeast WI until late Tuesday night due to persistent northerly winds up to 25 kt and 3 to 5 foot waves.

Cronce

MKX WATCHES/WARNINGS/ADVISORIES
WI
Beach Hazards Statement
WIZ052-WIZ060-WIZ066-WIZ071-WIZ072 until 10 AM Wednesday.

LM
Small Craft Advisory
LMZ643-LMZ644 until 1 AM Wednesday.

Small Craft Advisory...LMZ645-LMZ646 until 7 AM Wednesday.