


Area Forecast Discussion
Issued by NWS Green Bay, WI
Issued by NWS Green Bay, WI
Versions:
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
077 FXUS63 KGRB 131747 AFDGRB Area Forecast Discussion National Weather Service Green Bay WI 1247 PM CDT Sun Jul 13 2025 Updated aviation portion for 18Z TAF issuance .KEY MESSAGES... - Near-surface Canadian wildfire smoke will continue to result in poor air quality and reduced visibilities through Monday morning. An Air Quality Advisory remains in effect. - Next round of more widespread active weather arrives Tuesday afternoon into Wednesday. && .DISCUSSION... Issued at 257 AM CDT Sun Jul 13 2025 Rain chances... Some CAMs hint at a weak surface boundary passing over northern Wisconsin this afternoon, which could produce an isolated shower. This being said, just as many CAMs keep us dry throughout the day, though have opted to retain slight chance PoPs in the forecast. Similarly, a wrung-out frontal boundary and shallow mid-level shortwave may be enough to squeeze out a shower or two on Monday, although any resultant rainfall would be trivial compared to what we`ve seen over the past week. Next chances for more widespread precip then look to arrive sometime on Wednesday, accompanying a quasi-stationary front that sets up over central Wisconsin. Instability and moisture build along/south of the boundary during the afternoon as several transient shortwaves ride along predominantly zonal flow, although heavier rain or thunder potential would likely hinge on any north/south wobbles of the front. Will continue to monitor in the coming days. Smoke trends... Overnight obs show visibilities gradually rising in response to a lull in near-surface smoke activity. This brief reprieve will not be long-lived, however, as RAP/HRRR smoke guidance shows another bout of elevated smoke arriving later this morning. Some of this smoke may make it down to the surface provided some mixing occurs, with highest concentrations across northern Wisconsin. Westerly winds will then usher in yet another plume from out over Minnesota Monday morning. An Air Quality Advisory remains in effect until noon on Monday. && .AVIATION...for 18Z TAF Issuance Issued at 1247 PM CDT Sun Jul 13 2025 Smoke from Canadian wildfires will continue to move across the region at times through the TAF period, bringing poor air quality and mainly MVFR visibilities. The first batch will move through this afternoon into tonight, with a break in the thicker smoke (and the MVFR visibilities) expected to slowly work west to east across the area later today into tonight. Another batch of thicker smoke is forecast to move into northern WI Monday morning. Otherwise, look for daytime cu to continue through the afternoon then fade this evening. As a weak frontal boundary sags into and across the area overnight into Monday morning, a stray shower will be possible, but chances are under 20% and no impacts are expected, so will not include. Some mid-clouds will also likely accompany this boundary. A period of LLWS is possible over northern WI (RHI) overnight into early Monday as 2000 ft winds increase to 30-35 kts. It looks marginal and short-lived, so have confined it to just a few hours at RHI late tonight. && .GRB WATCHES/WARNINGS/ADVISORIES... None. && $$ DISCUSSION.....Goodin AVIATION.......Bersch