Forecast Discussion for GRB NWS Office
953
FXUS63 KGRB 021747
AFDGRB

Area Forecast Discussion
National Weather Service Green Bay WI
1247 PM CDT Tue Jun 2 2026

Updated aviation portion for 18Z TAF issuance

.KEY MESSAGES...

- Dry weather prevails through mid-week. Chances for showers and
  storms then return later this week and into the weekend.

- Above normal temperatures expected through the weekend, with
  highs reading mainly in the 80s.

- Elevated fire weather conditions possible through mid-week due
  to low relative humidity and above normal temperatures. Near-
  critical conditions may develop Wednesday afternoon as winds
  increase.

&&

.DISCUSSION...
Issued at 113 AM CDT Tue Jun 2 2026

Rain/storm chances... Blocking ridge holds steady over the CONUS
through mid-week, before eventually breaking down on Thursday. A
period of unsettled weather then sets in toward the end of the
week as several shortwaves migrate through the upper-level pattern
and prevailing southerly flow brings an influx of Gulf moisture
up into the Midwest. Though it is still too soon to pinpoint exact
timing and placement of heaviest rain, ensembles seem to hone in
on late Friday into Saturday for the bulk of the QPF to fall.
Probabilistic guidance shows a 30 to 50% chance for receiving half
an inch of rain during this time. Some storms will be possible
mainly Friday afternoon as surface-based instability (1,500 to
2,000 J/kg) builds in the vicinity of the surface low, though it
is still too soon to determine severe potential. Storm development
will likely hinge on frontal placement and timing of mid-level
shortwave.

Temperatures... Temperatures will remain steady in the upper 70s
to mid 80s (around 5 to 10 degrees above average) for the better
part of the week as a warming ridge dominates the Midwest.
Highs peak in the mid to upper 80s in/around the Fox Valley on
Thursday, though the chances for a 90 degree reading remain low
(10 to 30%). Shower timing and cloud cover may also mitigate
temperatures. Dewpoints will read comfortably in the mid to upper
50s during this time, resulting in a low heat risk of 1 out of 4.
Greater potential for heat-related impacts will come late this
weekend into early next week as dewpoints continue to rise.

&&

.AVIATION...for 18Z TAF Issuance
Issued at 1246 PM CDT Tue Jun 2 2026

Lake breeze winds (E/NE wind direction) will influence GRB/ATW/MTW
this afternoon. Winds will mainly be 10 kts or less, though gusts
may reach 15 kts at times. The rest of the TAF period will feature
light winds tonight, followed by light SW winds inland and locally
onshore winds near the bay and Lake Michigan on Wednesday morning.

VFR conditions will continue with high pressure in control. Scattered
high clouds today and tonight, will be followed by scattered cu late
Wednesday morning into Wednesday afternoon.

&&

.FIRE WEATHER...
Issued at 113 AM CDT Tue Jun 2 2026

Prolonged stretch of dry weather will result in elevated to near
critical fire weather potential through mid-week as afternoon RHs
fall into the 20 to 30% range across the sandy soil regions.
Despite widespread green up, fine fuels remain volatile given the
absence of soaking rainfall, with the main period of concern
being Wednesday afternoon when low RHs coincide with increasing
gradient wind. Winds currently look to remain just below critical
thresholds, though any increase would bear watching for
headline/SPS potential. Fire weather threat then diminishes
toward the end of the week with the arrival of scattered
rain/storms.

&&

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

&&

$$

DISCUSSION.....Goodin
AVIATION.......JLA
FIRE WEATHER...Goodin

NWS GRB Office Area Forecast Discussion