208 FXUS63 KGRB 071728 AFDGRBArea Forecast Discussion National Weather Service Green Bay WI 1228 PM CDT Tue Oct 7 2025
Updated aviation portion for 18Z TAF issuance
.KEY MESSAGES...
- Upgrade Freeze/Frost headlines for tonight as confidence increases for temperatures in the 20s and 30s.
- Near frost/freeze criteria again Wednesday night, headlines will likely be needed.
- A dry week with high temperatures near normal. Small chances for rain Friday and this weekend. Higher chances early next week.
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.DISCUSSION... Issued at 417 AM CDT Tue Oct 7 2025
A brief shower or sprinkles are still possible in the far southeastern forecast area for another hour or so as remaining shortwave energy departs. Otherwise, the focus is on temperatures for the next couple mornings as lows dip into the 20s and 30s for most locations.
Temperatures...A cooler and drier airmass is now in place which will result in daily temperatures averaging closer to normal this week. The cooler air, along with clear and calm nights, has increased confidence in frost/freeze conditions for tonight. Have already upgraded the Freeze Watch across northern and northeast WI for tonight/Wednesday morning to a Freeze Warning, plus expanded this headline to include central WI in a Freeze Warning, and issued a Frost Advisory for counties east through the Fox Valley. NBM probabilities show an ~70-95% chance of temperatures reaching 32F or colder across most of northern, far northeast, and parts of central WI tonight. Therefore, fairly confident in the Freeze Warning. A little tricker farther east and across the Fox Valley, as a slight northerly breeze may keep temperatures a little higher here. Regardless, seeing anywhere from 25-80% chance of reaching 36 or colder, which is cold enough for frost formation. Lakeshore counties will be in the lower 40s tonight, keeping them out of frost territory.
Wednesday night/Thursday morning is forecast to be a few degrees warmer, but probabilities of reaching 36F or colder north and west of the Fox Valley range from 25-95%, therefore frost/freeze headlines will likely be needed for parts of the forecast area. Low temps will be in the 40s and 50s for the rest of the week and into the weekend, well above frost territory.
Meanwhile, daily highs will be in the 60s through the week, with some lower 70s possible this weekend.
Precipitation...Chances for rain are very low through the work with with a large surface high pressure and upper ridging in control. A shortwave and surface front pass through late Friday or Saturday, which bring a small chance of precipitation. There is a higher chance of rain as a deeper trough comes through late this weekend or early next week.
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.AVIATION...for 18Z TAF Issuance Issued at 1222 PM CDT Tue Oct 7 2025
VFR flight conditions are expected through the TAF period.
A weak cold front will bring scattered cumulus and a narrow band of mid-level clouds as it moves through this afternoon and early evening. Otherwise, only expecting gusty winds shifting from W to NW/N in the wake of the front, then becoming light and variable as high pressure arrives overnight. There is a small chance of patchy ground fog late tonight, but confidence is too low to include at any of the TAF sites.
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.GRB WATCHES/WARNINGS/ADVISORIES... Freeze Warning from 10 PM this evening to 9 AM CDT Wednesday for WIZ005-010>013-018>021-073-074.
Freeze Warning from 3 AM to 9 AM CDT Wednesday for WIZ030-031- 035-036.
Frost Advisory from 3 AM to 9 AM CDT Wednesday for WIZ037>039- 045-048-049. &&
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DISCUSSION.....KLJ AVIATION.......Kieckbusch
NWS GRB Office Area Forecast Discussion