FXUS63 KGRB 152330 AFDGRB Area Forecast Discussion National Weather Service Green Bay WI 630 PM CDT Thu Oct 15 2026 Updated aviation portion for 00Z TAF issuance .KEY MESSAGES... - Ongoing, widespread rain this afternoon and evening, becoming scattered overnight into Friday. Probabilities for 1 inch or greater range from 60 to 90%. - Northwest winds increase on Friday, with gusts between 30 and 40 mph, and a 30% probability that lake shore counties could receive gusts to 45 mph. Gale force gusts are expected across marine zones. - A Freeze Watch has been issued for Friday night as temperatures are likely to fall into the upper 20s in locations away from Lake Michigan. && .DISCUSSION... Issued at 214 PM CDT Thu Oct 15 2026 Precip...Small adjustments/increases in QPF over the next 24 hours, otherwise forecast remains similar to the previous update. Moisture plume associated with sfc low/shortwave in the central Plains has been spreading northeast today and resulted in onset of widespread rain across central and northeast WI. Expect steady rain to continue this afternoon and evening, followed by rain becoming scattered overnight as two energy areas phase across the Great Lakes and move east. Lingering low-level moisture and trailing surface trough will keep widely scattered rain and drizzle in the forecast throughout Friday morning, and into the afternoon for the east. Event total rain amounts will range from approximately 0.75 to 1.10 inches, with probabilities of exceeding 1 inch of rain now ranging from 60 to 90%. Most of this will occur before 06Z/Fri, with around 0.20 inch or less after that time. Wind...As northern and southern stream lows approach from the northwest and southwest, then phase just east of WI, expect tightening pressure gradient to result in strong north to northwest winds on Friday. Gusts of 30 to 35 mph are forecast area wide. Potential for wind gusts reaching 45 mph are greatest near the lake shore, where this is a small potential for wind-related headlines. However, right now the probability of exceeding 45 mph gusts stands around 30%. See MARINE section for additional wind information. Temperatures...Cold front associated with northern stream low will usher in a cooler batch of air for a couple days. Clouds and wind will keep temps in the mid 30s and 40s tonight, but clearing skies and lights winds on Friday night will allow readings to fall below freezing in most locations. Probabilities range from 40 to 80% for a hard freeze, lows of 28 degrees or cooler, away from the lake shore counties. Therefore, a Freeze Watch was issued for all counties where the growing season continues, aside from Door County. Temperatures quickly start to rebound on Sunday with highs back in the 60s for several days. Next week...High pressure will result in low impact weather into at least the middle of next week, with temperatures AOA normal, little to no precip chances until at least Thursday, and light winds. && .AVIATION...for 00Z TAF Issuance Issued at 600 PM CDT Thu Oct 15 2026 Expect IFR cigs to persist through at least 06Z, though brief improvements to MVFR will be possible. Otherwise, main impacts to aviation will revolve around ongoing periods of light to moderate rain that are forecast to continue through Friday morning. Have thus gone prevailing SHRA with reduced vsbys at all TAF sites. Rain coverage then becomes more SCT late tonight into Friday morning, which should signal an improvement to more widespread MVFR cigs. Potential for cigs lifting to VFR then exists after 18Z. Northwesterly winds ramp up late Friday morning as rain comes to an end from west to east. Surface gusts between 30 and 40 mph are forecast for all terminals, peaking early Friday afternoon. A brief period of LLWS will be possible over RHI, AUW, and CWA early Friday morning as 850 mb winds increase. && .MARINE... Issued at 214 PM CDT Thu Oct 15 2026 Gradient winds on the back edge of the departing surface low ramp up Thursday night into Friday morning, putting us solidly within northwest flow and CAA regime. Deep daytime mixing will tap into 45 to 50 knot winds at 850 mb Friday afternoon, which will result in a brief window for gale force gusts over all marine zones through Friday evening. NBM probabilistic guidance continues to show a healthy signal (60 to 90%) for gusts exceeding 34 kts, highest along the Lake Michigan nearshore waters south of Kewaunee. Waves build 7 to 10 ft on the Lake and 4 to 7 ft on the Bay during this time, subsiding Friday night as winds shift to more westerly and the pressure gradient eases up. Gale Warning remains in effect. && .GRB WATCHES/WARNINGS/ADVISORIES... Freeze Watch from late Friday night through Saturday morning for WIZ020-030-031-035>040-045-048>050-073-074. && $$ DISCUSSION.....KLJ AVIATION.......Goodin MARINE.........Goodin/KLJ