089 
FXUS63 KGRB 110905
AFDGRB

Area Forecast Discussion
National Weather Service Green Bay WI
405 AM CDT Wed Mar 11 2020

Forecast discussion for routine morning forecast issuance

.SHORT TERM...Today...Tonight...and Thursday
Issued at 401 AM CDT Wed Mar 11 2020

The short term forecast is focused on the two rounds of
precipitation, the first ending this morning and the second
arriving late Wednesday night into Thursday.

Snow will continue across the region this morning, exiting by the
middle to late morning hours. A quick inch or two of accumulation
will likely create some slick areas for the morning commute. 
The back edge of this system is eroding rapidly, so dry 
conditions are expected to return by the late morning. Cloud cover
will linger on through the afternoon and evening however, as 
temperatures rise into the upper 30s to middle 40s.

WAA advection will pick up tonight ahead of the next shortwave,
which will keep low level clouds in place overnight, but will also
keep low temperatures up in the 30s. Frontogenesis along the 
leading edge of the warm front could bring some rain and snow 
showers to northern Wisconsin, but widespread precipitation will 
hold off until the daylight hours and the arrival of a shortwave.
Any early snowfall will likely not accumulate much with the warm 
surface temperatures.

Widespread rainfall is forecast for Thursday afternoon and evening
as the shortwave heads to the region. QPF amounts range from a
quarter to around half an inch total, which will further
exasperate the flood potential for area rivers. Strong WAA ahead 
of the cold front and accompanying shortwave will allow 
temperatures to push into the lower to middle 40s and even lower 
50s during the afternoon. This event then continues into Thursday
night. Please see the extended discussion for details.

.LONG TERM...Thursday Night Through Tuesday
Issued at 401 AM CDT Wed Mar 11 2020

The main highlights from this forecast period are the continued 
chances for precipitation into Thursday night, followed by a quiet 
pattern to end the work week and weekend. The next chance for an 
unsettled pattern returns next week. 

Thursday night into Friday morning...A cold front will be in the 
process of exiting the region Thursday night. Most of the western 
portion of the forecast area will have already seen the bulk of the 
precipitation earlier on Thursday. Since the axis of precipitation 
appears to remain tethered to the cold front, with some trailing, 
eastern Wisconsin will continue to see rain into Thursday night. A 
period of moderate to heavy rain is possible heading into Thursday 
night as there appears to be a decent amount of f-gen with this cold 
front. In addition, the forecast area will also be under the favored 
left front quadrant of the upper-level jet. As boundary layer 
temperatures fall below freezing into Thursday night, especially 
across north-central Wisconsin, it is possible for some snow or 
freezing rain to mix in before ending around midnight Friday. Model 
guidance continues to show some signs of lingering light snow over 
far north-central Wisconsin into early Friday morning. Little to no 
snow accumulations are anticipated. The additional rainfall will add 
to the localized and river flooding concerns, as well as ice jams.

Friday through Sunday...A relatively quiet pattern will then set up 
for the weekend as a large area of high pressure moves over the 
forecast area. Temperatures are expected to be near or slightly 
above normal through this time period.

Rest of the extended...The large area of high pressure will shift 
well to the east of the forecast area by Sunday night. A surface low 
pressure system is then expected to slide over northeastern 
Minnesota and western Ontario into early Monday morning. The 
associated cold front could bring the next chance for precipitation 
to the forecast area sometime between Monday night and Tuesday. 
However, model guidance differs with the amount of precipitation 
associated with this cold front and when the frontal passage will 
occur over the forecast area.
&&

.AVIATION...for 06Z TAF Issuance
Issued at 1002 PM CDT Tue Mar 10 2020

A steady light snow is expected to overspread central and eastern
WI overnight. The snow will taper off from west to east late 
tonight into Wednesday morning, before ending near the lakeshore 
around 15z/Wed. Most location will have MVFR/IFR conditions 
overnight into Wednesday morning, with improving conditions 
Wednesday afternoon. VFR condition may return to north central and
far northeast WI in the late morning and afternoon, before
returning to MVFR Wednesday evening.

Plowing operations will be needed in some areas, with 2-3 inches 
of wet snow possible from Y50-OSH-MTW, and an inch or two at most 
other airports in central and east central WI.
&&

.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

SHORT TERM.....Uhlmann
LONG TERM......Hykin
AVIATION.......Kieckbusch