Small Craft Advisory 10, NWS Green Bay, WI

Area Forecast Discussion
National Weather Service Green Bay WI
450 PM CST Mon Jan 20 2020

Updated aviation portion for 00Z TAF issuance

.SHORT TERM...Tonight and Tuesday
Issued at 224 PM CST Mon Jan 20 2020

Sunny skies prevailed across much of the region this afternoon.
The only exception was from Merrill southward through Wausau and
Stevens Point where skies were mostly cloudy.

The low clouds will dissipate by sunset, otherwise clear skies
are expected. The main question is how low will temperatures
fall later this evening into early Tuesday morning before winds
increase towards sunrise, especially across the north. Went
lower than the colder guidance values of the MAV in the typical
cold spots.

Mostly sunny skies will prevail on Tuesday. Winds will be on
the increase during the late morning and afternoon to add a
chill to the air. High temperatures should warm into the lower
to middle 20s.

.LONG TERM...Tuesday Night Through Monday
Issued at 224 PM CST Mon Jan 20 2020

The main concern in the extended portion of the forecast will be the
potential for unsettled weather toward the middle and end of the
work week. In addition, temperatures are expected to be about 10
degrees above normal for the end of the week into the weekend.

Tuesday night: A broad surface ridge will linger across the area
through much of the night as it slowly shifts to the east. This will
keep much of the area dry; however, an increase in mid to high cloud
cover can be expected overnight as return southerly flow increases.
Overnight lows are expected to be in the teens above zero.

Wednesday into Wednesday night: The next chance of precipitation
will move into the area during the afternoon as the surface ridge
begins to slide farther off to the east. This will allow moisture to
advect northward along with warmer air. Added forcing will occur
along and ahead of a surface trough sliding across MN. This trough
is expected to stall across the area Wednesday night, allowing for
continued chances of precipitation across much of the area. Moisture
looks to be deep enough for this time period to keep precipitation
in the form of light snow; however, some freezing drizzle may mix in
at times over central and north-central. Dry low-level air will
linger across east-central and far northeast WI, which will likely
delay the onset of precipitation chances until late morning or early
afternoon as reflected in the latest grids. Models are only painting
out between 0.10 and 0.20 inches of QPF, which would lead to roughly
1 to 3 inches across the area with snow-to-liquid ratios around or
just above 10:1. The higher totals will likely remain across
central/north-central WI, where better forcing is along the front
before it stalls out and near a shortwave passing through the area.
High temperatures will be in the upper 20s to near 30.

Thursday through Friday: Broad high pressure over the East Coast is
expected to allow moist southerly flow to push northward from the
Gulf. The aforementioned, nearly stationary trough, is expected to
drift slowly southeastward Thursday through Friday, allowing
continued chances of precipitation near the trough. Low-level
temperatures may warm enough and moisture may occasionally shallow
out enough that the snow mixes with rain/drizzle or possibly
freezing rain/drizzle at times. Convergence is expected to be fairly
weak along the trough, but may be just enough to produce light
precipitation. A stronger surface low and upper-level closed low is
expected to slide across the mid-Mississippi Valley Thursday.
Moisture will continue to stream around this low and into the Upper
Great Lakes. This will keep an extended period of light wintry mix
of snow/drizzle/freezing drizzle through much of this time period.
Only light/spotty QPF is being painted out in the models, with
generally a tenth of an inch or less expected Thursday into Friday,
which makes sense with fairly weak forcing in place. Temperatures
are expected to moderate through this time period with highs warming
into the mid 30s with overnight lows in the upper 20s to low 30s.

Rest of the extended: A break in the precipitation is expected for
the upcoming weekend as brief and dry surface/upper-level ridge
passes through the area. Didn't make many changes from the model
blends for this time period. Temperatures are expected to run about
10 degrees above normal, with most locations in the low to mid 30s.
&&

.AVIATION...for 00Z TAF Issuance
Issued at 443 PM CST Mon Jan 20 2020

Statistical guidance hints at some reduction of visibility
occurring in central/north-central Wisconsin as a low-level
inversion strengthens overnight. Will introduce this into the
TAFS as a 2-3SM prevailing visibility (BR) for now, though it may
end up manifesting itself with much larger fluctuations between
unrestricted visibility and LIFR conditions. Will consider adding
a tempo group for the lower conditions with the next issuance if
conditions continue to look favorable. LLWS will also be
increasing across the area late tonight and Tuesday.
&&

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

SHORT TERM.....Eckberg
LONG TERM......Cooley
AVIATION.......Skowronski

Hazardous Weather Outlook
National Weather Service Green Bay WI
225 PM CST Mon Jan 20 2020

WIZ005-010>013-018>022-030-031-035>040-045-048>050-073-074-212030-
Vilas-Oneida-Forest-Florence-Northern Marinette County-Lincoln-
Langlade-Menominee-Northern Oconto County-Door-Marathon-Shawano-
Wood-Portage-Waupaca-Outagamie-Brown-Kewaunee-Waushara-Winnebago-
Calumet-Manitowoc-Southern Marinette County-
Southern Oconto County-
225 PM CST Mon Jan 20 2020

This Hazardous Weather Outlook is for north-central and northeast
Wisconsin.

.DAY ONE...Tonight

The probability for widespread hazardous weather is low.

.DAYS TWO THROUGH SEVEN...Tuesday through Monday

Light snow, potentially mixed with freezing rain or freezing
drizzle at times, is expected Wednesday through Friday. Only minor
accumulations are expected at this time; however, the
precipitation may lead to slippery travel.

.SPOTTER INFORMATION STATEMENT...

Spotter activation will not be needed tonight.

LMZ521-522-541>543-212030-
The Bay of Green Bay south of a line from Cedar River MI to Rock
Island Passage-Lake Michigan from Washington Island to Sheboygan-
225 PM CST Mon Jan 20 2020

This Hazardous Weather Outlook is for portions of northwest Lake
Michigan and the waters of Green Bay.

.DAY ONE...Tonight

The probability for widespread hazardous weather is low.

.DAYS TWO THROUGH SEVEN...Tuesday through Monday

The probability for widespread hazardous weather is low.

Eckberg/Cooley