Lower First Lake Wisconsin Weather Forecast Discussion

169
FXUS63 KGRB 141931
AFDGRB
Area Forecast Discussion
National Weather Service Green Bay WI
231 PM CDT Tue Oct 14 2025
.KEY MESSAGES...
- Showers will increase late this afternoon into tonight, but
  amounts will be generally light with 20 to 40% chances for at
  least 1/4 inch.
- Intermittent showers Thursday into the weekend with a small
  (10-30%) chance for non-severe thunderstorms Thursday night
  into Friday night.
- Seasonable temperatures will prevail through the middle of the
  week with well above average temperatures in the 60s to low
  70s for Friday and Saturday.
&&
.DISCUSSION...
Issued at 230 PM CDT Tue Oct 14 2025
Tonight-Wednesday: Showers Tonight
Despite the influence of Canadian high pressure across the Upper
Great Lakes region, radar mosaics showed returns extending from
Minnesota/Iowa into western/central Wisconsin in association
with mid-level warm advection/frontogenesis. 12Z GRB/MPX
soundings showed substantial dry air below 700 mb with more
moisture present in the mid-levels at MPX. Despite the stubborn
dry air in place, some light rain has been reported within the
higher returns nosing eastward from central Wisconsin this
afternoon. The higher chances for more widespread showers
(60-90% chance) come late today/tonight when mid-level
frontogenesis is strongest. However, rain amounts will generally
be modest with only low (20-40%) chances of exceeding 1/4 inch,
mainly across central Wisconsin per the HREF. Much of the day
on Wednesday looks dry and seasonable as the shortwave trough
pushes east and high pressure is the dominant influence.
Thursday-Sunday: Warmer, unsettled at times
Broad mid-level ridging and return southerly flow will start to set
up on Thursday ahead of a deep trough and associated surface low
that will lift northeast from the Rockies into the northern plains
late this week, eventually dragging a cold front through over
the weekend.
Warm advection will increase ahead of a warm front Thursday into
Thursday night with medium (40-60%) chances for showers. Although
any instability looks quite weak, an isolated thunderstorm (

NWS GRB Office Area Forecast Discussion