Area Forecast Discussion
Issued by NWS Green Bay, WI

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FXUS63 KGRB 301951

Area Forecast Discussion
National Weather Service Green Bay WI
251 PM CDT Mon Mar 30 2020

Forecast discussion for routine afternoon forecast issuance

.SHORT TERM...Tonight and Tuesday
Issued at 250 PM CDT Mon Mar 30 2020

The main forecast issue to be on cloud trends and their impact on
temperatures over the next 24 hours.

The 19Z MSAS surface analysis showed low pressure well to our east
over extreme southeast Ontario with a ridge of high pressure that
stretched from near Hudson Bay southwest into MN, then south
through the Midwest. Visible satellite imagery showed wrap-around
clouds across eastern WI with mostly sunny to partly sunny sunny
skies across central WI.

Even as the surface ridge of high pressure moves into WI tonight,
a northeast wind will combine with CAA to send lake-induced clouds
westward across the forecast area. Eastern WI may not be able to
clear at all with clouds retrograding into central WI after
midnight. As mentioned in the previous discussion, a few models
attempt to bring lake-enhanced precipitation into eastern WI
tonight, however any activity appears too isolated to mention in
the forecast (perhaps sprinkles/flurries). Min temperatures to
range from the lower 20s north-central WI, to around 30 degrees
east-central WI.

The cloud battle of drier air from the high pressure versus the
more moist air from the northeast wind/CAA will continue into
Tuesday with central WI more likely to see at least some filtered
sunshine, whereas eastern WI appears stuck under mostly cloudy
skies. Max temperatures on Tuesday to range from around 40 degrees
near Lake MI, to the upper 40s over parts of central WI.

.LONG TERM...Tuesday Night Through Monday
Issued at 250 PM CDT Mon Mar 30 2020

A relatively quiet period is in store for much of the week as
large scale ridging remains in place across the western Great
Lakes region. Temperatures will be around normal through the
middle of the week, then soar to above normal by the end of the

The ridge will slide east late in the week, which will
allow a trough of low pressure to push towards the western Great
Lakes region. The trough will bring a surface low pressure system
through the region, which will bring another round of
precipitation Friday and Saturday. Precipitation amounts from this
system are expected to be light, with less than an inch expected.
Despite the light rainfall amounts, any additional rainfall could
exacerbate flooding on area rivers.

The low will push east on Sunday, providing dry conditions to the
area for the second half of the weekend. Another low pressure
system could bring another round of rain early next week, however
model solutions are in a bit less agreement that far out.

.AVIATION...for 18Z TAF Issuance
Issued at 1235 PM CDT Mon Mar 30 2020

MVFR/VFR low clouds continue to rotate around the backside of the
system that brought all the rain to northeast WI this past
weekend. Central WI to see more sun this afternoon with a sct-bkn
cumulus deck of 3500-5000 ft with these clouds briefly dissipating
after sunset into the evening hours. Eastern WI to see more of a
bkn deck of cigs in the 2500-3500 ft range that will persist until
late afternoon or early evening. However, as winds turn northeast
and CAA occurs, expect these clouds to redevelop/retrograde back
to the west this evening such that cigs will return to the MVFR
category from east to west, reaching central WI after midnight.
These low clouds would then persist into Tuesday morning before
rising into a VFR deck from late morning through Tuesday

Issued at 250 PM CDT Mon Mar 30 2020

Runoff from recent heavy rain continues to bring sites along the
Wisconsin, Wolf, Peshtigo, Oconto, Embarrass and Menominee Rivers
above Flood Stage. A number of other locations have seen water
levels go above bankfull. Water levels should continue to slowly
rise early this week and peak mid-week, before starting to fall.
Residents living near rivers or streams should closely monitor
water levels and be prepared to seek higher ground if flooding
becomes imminent.



SHORT TERM.....Kallas
LONG TERM......Kurimski
HYDROLOGY......Kallas is the U.S. government's official web portal to all federal, state and local government web resources and services.