Fort Atkinson, WI 53538 Weather

Key Messages

- Low clouds and fog may develop and/or move in from the north/northeast into tonight and linger into Friday morning. Eastern parts of the area would be most affected. Dense fog is possible as well.

- Above normal temperatures and dry conditions will continue into the weekend.

- Temperatures trending cooler for early next week with northeast winds. There are some chances (20 to 30 percent) for showers for the middle to later portions of next week.

Short Term

Issued 233 PM CDT Thu Oct 22 2026

Tonight through Friday night:

The main issue will be the low stratus and fog deck that may shift south southwest into eastern portions of the area into tonight and Friday morning. The current low stratus deck with some light fog is lingering over portions of northern Lake Michigan into northeast Wisconsin, and hugging the shoreline southward at Sheboygan and Port Washington. This area has mixed out somewhat with daytime heating over far northern Lake Michigan and eastern Lake Michigan. This may continue through later this afternoon with peak heating.

However, think that the more solid area of low stratus and light fog over northeast Wisconsin into the western portions of Lake Michigan probably will hold on into tonight and Friday morning. Short term models are showing this area shifting south southwest into eastern portions of the area, especially near Lake Michigan, into this evening and lingering into Friday morning. Given that high pressure well to the east will continue to bring light southeast winds, moisture off of the lake may help to solidify this area of low stratus and fog.

Dense fog is possible as well into Friday morning, given the light winds and low stratus clouds possibly sinking toward the ground under the inversion. For now, will continue to bring in these low stratus clouds and fog into eastern parts of the area into this evening and linger into Friday morning. Later shifts will need to monitor the progress of the low stratus deck and visibility drops in case any Dense Fog Advisories are needed.

Once the low clouds and fog mix out later Friday morning, another mild and dry day is expected for Friday, with middle to high clouds gradually moving into the area Friday night. Lows tonight and Friday night should be in the upper 40s southeast to lower 50s northwest. Highs Friday should reach the lower to middle 70s inland, with upper 60s closer to the lake with onshore flow.

Long Term

Issued 233 PM CDT Thu Oct 22 2026

Saturday through Thursday:

500 mb cluster analysis continues to show an anomalous ridge axis over the Great Lakes region Saturday gradually shifting eastward Sunday into Monday, with flow becoming more zonal across the region. At the surface, south to southwest winds should continue to maintain dry conditions and warm temperatures Saturday into Sunday. Highs should continue to be in the upper 60s to lower 70s each day, with a southeast lake breeze possible Saturday afternoon near the lake. Ensemble members are supportive of these values and the ensemble spreads are very small, indicating higher confidence.

Models then show a cold front slowly shifting southeast toward or through the area Sunday night or Monday, with winds shifting to the northeast behind the front later Monday into Monday night. The front may not have much moisture to work with, so any shower chances look minimal (under 15 percent) at this time. There should be some clouds that occur during this time. Temperatures should cool off Monday with the northeast winds, with highs more seasonable values in the upper 50s to middle 60s.

Ensemble members are rather mixed for shower chances through next week, as there is disagreement with the timing and placement of low pressure moving through the region. Kept NBM precipitation chances for now (20 to 30 percent) for Wednesday into Thursday, until more clarity can be found. Temperatures look to be a little above seasonal normal values.

Wood

Aviation

Issued 233 PM CDT Thu Oct 22 2026

The current low cloud deck with some light fog is lingering over portions of northern Lake Michigan into northeast Wisconsin, and hugging the shoreline southward toward Sheboygan and Port Washington. A more solid area of low clouds around 300 to 500 feet AGL and light fog of 1 to 4 miles may shift south southwest into eastern portions of the area, especially for terminals near Lake Michigan, into this evening and lingering into Friday morning. Given that high pressure well to the east will continue to bring light east to southeast winds, moisture off of the lake may help to solidify this area of low clouds and fog.

Dense fog down to one quarter mile or less is possible as well into Friday morning for terminals near Lake Michigan, given the light winds and low clouds possibly sinking toward the ground. For now, will continue to bring in these low clouds and light fog into terminals near Lake Michigan into this evening and linger into Friday morning. Later shifts will need to monitor the progress of the low clouds and visibility trends for any dense fog.

Once the low clouds and fog mix out later Friday morning, another mild and dry day is expected for Friday, with middle to high clouds gradually moving into the area Friday night. Winds will be light and southerly on Friday, with southeast winds for terminals near Lake Michigan. Light winds will be south southeast Friday night.

Wood