FXUS63 KGRB 290834

Area Forecast Discussion
National Weather Service Green Bay WI
334 AM CDT Fri May 29 2020

Forecast discussion for routine morning forecast issuance

.SHORT TERM...Today...Tonight...and Saturday
Issued at 330 AM CDT Fri May 29 2020

Much quieter and more comfortable humidity values expected through
the short-term portion of the forecast. River levels will likely
continue to run high into the weekend with a few rivers expected to
reach minor flood stage.

Today: As a trough axis/shortwave passes through the area, expect
some late morning/afternoon instability showers/sprinkles to
develop. Most locations will remain dry; however, skies will become
partly cloudy during the day for a majority of the area. Otherwise,
temperatures are expected to be be cooler and humidity levels more
comfortable across the area. Highs are expected to be in the 60s.

Tonight and Saturday: As the aforementioned shortwave passes east of
the area during the evening, expected diurnal cloud cover to
decrease. This will allow temperatures to drop into the upper 30s
north-central with perhaps some patchy frost. Coverage is not
expected to be widespread enough for an advisory. The rest of the
area will likely see temperatures drop into the 40s. Another
shortwave is expected to brush along the WI/UP border late tonight
into Saturday morning, which may lead to a few sprinkle or light
rain showers, but most locations should stay dry once again.
Otherwise, expected partly cloudy skies to develop during the day
Saturday. High temperatures are expected to be in the 60s for most

.LONG TERM...Saturday Night Through Thursday
Issued at 330 AM CDT Fri May 29 2020

Longwave trough over the eastern CONUS and Great Lakes region will
gradually shift eastward over the weekend as broad mean ridge
becomes established over the central CONUS by early next week.
Shortwave disturbances are forecast to occasionally move over the
top of the mean ridge position impacting the northern CONUS and
western Great Lakes region during the first half of the work week,
with mean ridge becoming restablished over the central CONUS by
the end of the week.

Early in the extended, western Great Lakes will be dominated by
large surface high pressure system forecast to be centered over WI
on Sunday. Thus, fair skies and cool temperatures can be expected
throughout the upcoming weekend. Temperatures on Sunday are
expected to be at or perhaps a few degrees below normal for the
end of May with highs near 70 inland and in the mid 60s near the
lake. Some frost potential exists for northcentral Wiscosnin very
early Sunday morning with light winds and mostly clear skies.
Morning lows could approach the freezing mark in the typical cold

Next chance for precipitation still looks to be sometime Monday
night into Tuesday morning as shortwave disturbance and associated
WAA impacts the area. This system will be rather progressive and
will have somewhat limited moisture so precipitation amounts look
to be on the light side and focused more across northern
Wisconsin. A somewhat more potent disturbance will quickly
approach during the day on Wednesday. However some uncertainty on
location of frontal boundary positioned just to the south of the
Wisconsin. Concensus of the model guidance suggests bulk of
precipitaiton will be focused along the boundary mainly south of
the area. For now will maintain low-end broad pops over the
forecast area.

For the rest of the work week confidnece is low on precipitation
chances as model guidance struggling with intensity and timing of
shortwave disturbances riding over the top of mean ridge position
and location of frontal boundary. Will stick with low end pops
offered by the blended guidance for now. Also leaned toward
blended guidance on temperatures with highs generally in the 75 to
80 degree range and lows in the upper 50s.


.AVIATION...for 06Z TAF Issuance
Issued at 1058 PM CDT Thu May 28 2020

Skies will clear overnight as a cold front moves away
from the area.

Skies should be clear early in the day Friday, with some cumulus
clouds forming by midday. MVFR ceilings are possible north of a
RHI to IMT line, along with a few sprinkles or light rain showers.
The rest of the area should have VFR ceilings.

Good flying weather is expected Friday night and Saturday.



SHORT TERM.....Cooley
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