386
FXUS63 KGRB 130800
AFDGRB

Area Forecast Discussion
National Weather Service Green Bay WI
300 AM CDT Sun Jul 13 2025

Forecast discussion for routine morning forecast 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 06Z TAF Issuance
Issued at 1053 PM CDT Sat Jul 12 2025

Reduced VSBYs due to near-surface smoke will be the primary
aviation concern.

Smoky conditions had improved late this evening, except across far
northern WI. The improvement will be short-lived, as smoke models
show near-surface smoke returning Sunday morning, then lingering
through evening. The thickest smoke will set up across the
northwest part of the forecast area, where vsbys may drop to IFR
at times. Farther southeast, vsbys will probably drop to 4-6sm at
times. Otherwise, expect dry conditions through the period, with
only SCT daytime cumulus development on Sunday.

Light SW-W winds are expected overnight, with gusty SW winds
returning during the daytime on Sunday.

&&

.GRB WATCHES/WARNINGS/ADVISORIES...
None.

&&

$$

DISCUSSION.....Goodin
AVIATION.......Kieckbusch