997 FXUS63 KMKX 110945 AFDMKXArea Forecast Discussion National Weather Service Milwaukee/Sullivan WI 445 AM CDT Thu Sep 11 2025
.KEY MESSAGES...
- Dense Fog Advisory in effect until 10 AM CDT this morning for parts of east central and southeast Wisconsin. Patchy dense fog may occur elsewhere into this morning, with more patchy dense fog possible later tonight into early Friday morning.
- Chances (20 to 35 percent) for showers and thunderstorms later Friday night into Saturday morning.
- High temperatures climbing above normal through the weekend, with humidity increasing as well.
&&
.SHORT TERM... Issued 445 AM CDT Thu Sep 11 2025
Today through Friday night:
An area of dense fog will continue to shift southwest across parts of east central and southeast Wisconsin into this morning, with a northeast fetch off of Lake Michigan. The Dense Fog Advisory was expanded to the west to account for this movement. The Dense Fog Advisory remains in effect until 10 AM CDT this morning in these areas. There may be patchy dense fog elsewhere into the morning hours, though the lingering middle level cloud cover is limiting most of this development. Areas that have some holes in the cloud cover may see the patchy dense fog. The fog should mix out by middle morning.
The current clouds may linger into or perhaps through today, though there should be some mixing out of these clouds as the day goes on. There should also be some diurnal scattered cumulus clouds that develop in the afternoon. Highs in the upper 70s are forecast inland, with lower to middle 70s closer to the lake with the modest easterly winds.
High pressure to the east of region should keep things dry tonight into Friday. There may be more fog and low stratus clouds that move southwest into the lakeshore counties later tonight into early Friday morning, though confidence is low as the low level flow becomes more easterly off the lake/shorter fetch. There is some indication for patchy dense fog in low lying areas overnight into early Friday morning as well. For now, kept patchy fog in the forecast. Southeast to south winds on Friday should bring highs into the lower to middle 80s inland, with 70s closer to the lake.
As the 500 mb ridge axis shifts across the region Friday night, there may be a shortwave trough that moves southeast through. There is uncertainty with where the surface warm front may move into Friday night, and subsequent chances for showers and some thunderstorms. For now, kept 20 to 35 percent chances going later Friday night into early Saturday morning.
Wood
&&
.LONG TERM... Issued 445 AM CDT Thu Sep 11 2025
Saturday through Tuesday:
As the shortwave trough moves through and exits the state to the southeast Saturday morning, any lingering showers and storms will also exit to the southeast. The larger upper level (500 mb) pattern will remain fairly similar through the weekend, with an upper level ridge over the Great Lakes Region. This ridge will be shifting eastward over time, with its central axis making its way into Michigan by early next week. This will create a prolonged period of largely dry weather.
From one guidance to another or one run to another there are some additional shortwave troughs that try to move through the flow and undercut the ridge. Some low chance POPs have therefore made it into the extended forecast, due to the shortwave troughs when guidance starts to line up just a bit, but PoP chances top out around 15 to 20 percent.
Dry low level air leads to some skepticism if Wisconsin will even get rain if a shortwave moves through. Due to our proximity to the central axis in the ridge, warm air advection will remain and temperatures should be in the upper 70s to potentially upper 80s through much of the extended. Looking further into the middle of next week, guidance does have a signal for this ridging to finally break down.
Patterson
&&
.AVIATION... Issued 445 AM CDT Thu Sep 11 2025
An area of dense fog to one quarter mile or less at times will continue to shift southwest across parts of east central and southeast Wisconsin into this morning, affecting the terminals at Milwaukee, Waukesha and Kenosha. There may be patchy dense fog elsewhere into the morning hours, though the lingering 6000 foot AGL ceilings are limiting most of this development. Areas that have some holes in the cloud cover may see the patchy dense fog. The fog should mix out by middle morning.
The current ceilings may linger into or perhaps through today, though there should be some mixing out of these clouds as the day goes on. There should also be some diurnal scattered cumulus clouds around 4000 feet AGL that develop in the afternoon. Modest easterly winds are expected today.
High pressure to the east of region should keep things dry tonight into Friday. Light winds are expected again tonight, becoming southeast to south on Friday.
There may be more fog and low ceilings that move southwest into the terminals near the lake later tonight into early Friday morning, though confidence is low. There is some indication for patchy dense fog in low lying areas overnight into early Friday morning as well.
Wood
&&
.MARINE... Issued 445 AM CDT Thu Sep 11 2025
High pressure around 30.3 inches near James Bay will shift east into Quebec today, with northeast winds expected. Some dense fog will linger into this morning east of Sheboygan to Wind Point to mid lake, where a Dense Fog Advisory is in effect until 10 AM CDT. A Dense Fog Advisory is in effect as well for the nearshore waters of Lake Michigan until 10 AM CDT. Patchy dense fog may occur over other portions of the lake as well.
High pressure will continue to move southeast into New England on Friday. Low pressure around 29.7 inches should move into the northern Great Plains, allowing winds to turn south to southeast. Showers and some thunderstorms are expected to move through the region Friday night into Saturday, with south winds increasing.
Winds will turn back out of the northeast Saturday night into Sunday, as a frontal boundary shifts south and high pressure around 30.2 inches develops in Quebec.
Wood
&&
.MKX WATCHES/WARNINGS/ADVISORIES... WI...Dense Fog Advisory...WIZ052-WIZ059-WIZ060-WIZ065-WIZ066-WIZ070- WIZ071-WIZ072 until 10 AM Thursday.
LM...Dense Fog Advisory...LMZ643-LMZ644-LMZ645-LMZ646-LMZ669-LMZ671- LMZ673 until 10 AM Thursday.
&&
$$
Visit us at weather.gov/milwaukee
Follow us on Facebook, X, and YouTube at: www.facebook.com/NWSMilwaukee www.x.com/NWSMilwaukee www.youtube.com/NWSMilwaukee
NWS MKX Office Area Forecast Discussion