Area Forecast Discussion
Issued by NWS Green Bay, WI

Home | Current Version | Previous Version | Graphics & Text | Print | Product List | Glossary Off
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42

000
FXUS63 KGRB 142112
AFDGRB

Area Forecast Discussion
National Weather Service Green Bay WI
412 PM CDT Thu Mar 14 2024

Forecast discussion for routine afternoon forecast issuance

.KEY MESSAGES...

- Sharp northern edge of rain lifting from the south will result
  in little if any rainfall reaching north of Highway 10 the rest
  of today. Whatever rain occurs will end by early this evening.

- A system dropping south out of Canada will bring a few chances
  for snow showers this weekend, mainly across northern WI.

- Northwest winds may gust to 30 to 40 mph on Saturday, strongest
  across central and far northeast WI, and east of Lake Winnebago.

- Temperatures remain 5 to 10 degrees above normal through
  Saturday before falling to more seasonable readings Sunday into
  Monday.

&&

.DISCUSSION...
Issued at 411 PM CDT Thu Mar 14 2024

Short Term...Tonight and Friday

A sfc wave of low pressure near Chicago will only ride as far north
as southern Lake Michigan while northeast winds out of high pressure
to the north continue to funnel in dry low-level air to north-central
and northeast Wisconsin. This net result of this setup will be that
most areas north of highway 10 will stay mainly dry the rest of the
afternoon. Radar and sfc obs show that north edge of shield of
rain spurred on by low-mid level frontogenesis is still south of
Wautoma but has reached Oshkosh and Manitowoc. Northern edge of
the rain lines up more with the area of H7 frontogenesis and this
may have another few hours to drift north (while still staying
south of highway 29), before the main shortwave over southern
Wisconsin shifts eastward late this afternoon into early evening.

Where rain does occur this afternoon it will end by early this
evening. Dry weather will follow the rest of tonight into Friday.
There could be a brief period when skies become mostly cloudy over
over northern Wisconsin on Friday due to weak cold air advection
and northwest flow across Lake Superior, but overall balance of
the time will be partly to mostly sunny over the forecast area.
Temperatures will be similar to today, though many locations from
central into northeast Wisconsin will see readings into the lower
50s with mostly sunny skies and lighter winds compared to the cloudy
skies and stiff northeast winds off the lake and bay that are
occurring today.

Long Term...Friday Night Through Thursday

Main highlights from this forecast period revolve around a pattern
shift to an upper-level cyclonic flow setting up over the James
Bay/Quebec area through early next week.

Precipitation...The cyclonic flow will set up near the region
beginning late Friday night into Saturday as a nearly stacked low
tracks east/southeast across Ontario. This will bring the first
round of precip chances as the system`s cold front sweeps across the
region during this time. Moisture appears to be limited, but there
should be enough to generate light rain or snow showers, or
sprinkles or flurries across the forecast area. CAA will fill in
behind the front as winds turn northwest, turning on the lake-effect
snow machine in far north-central WI. The best chances for lake-
effect snow will be from Saturday night through Sunday, as delta Ts
of 13 to 17 will combine with the favorable northwest wind
direction. The lake-effect snow showers may continue into Monday as
well. The highest probabilities for 1 inch or more of snow are in
far northwest Vilas County, with a sharp gradient to lower probs
across the rest of the county.

Winds...As the nearly stacked low tracks east/southeast across
Ontario Friday night into Saturday, the pressure gradient will
tighten towards the surface and cause west winds to increase.
Following the frontal passage on Saturday, the presence of strong
CAA will cause gusty northwest winds at the surface, with gusts of
30 to 40 mph. The highest probabilities for these strong winds will
be across central and far northeast WI, and east of Lake Winnebago.
The gusty winds will decrease Saturday night, but increase again on
Sunday with gusts up to 30 mph due to the continued CAA. Winds will
finally subside into Sunday night.

Temperatures...Despite the cold frontal passage late Friday night
into Saturday, the coldest air will not arrive until Sunday. High
temperatures on Saturday will range from the low 40s in north-
central WI to low 50s in east-central WI. About a 15 degree
difference is expected for Sunday`s high temperatures with readings
ranging from the middle 20s in north-central WI to the upper 30s in
east-central WI. Similar temperatures are expected for Monday before
slowly warming into the 40s for Tuesday through midweek.

&&

.AVIATION...for 18Z TAF Issuance
Issued at 1236 PM CDT Thu Mar 14 2024

Northeast winds with a feed of dry low-level air flowing out of
high pressure is keeping the majority of rain at bay to the south
as low pressure wave only makes it as far north as southern Lake
Michigan. Have removed any mention of rain at even the southern
TAF sites of ATW and MTW. Otherwise, overcast mid and high clouds
will impact all TAF sites through the afternoon before clouds
scatter out this evening. Northeast winds will gust over 20 kts at
GRB and ATW before diminishing by this evening.

Rest of TAF period at all the terminals will mainly feature VFR
conditions and lighter winds. A period of stratocu clouds may
impact RHI on Friday, but cigs will remain VFR.

Looking ahead, strong and gusty west to northwest winds (wind
gusts possibly over 30 kts) will occur at all terminals on
Saturday as a cold front sweeps across the region. The greatest
chances for any rain and snow on Saturday will be from RHI to the
north.

&&

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

&&

$$

DISCUSSION.....JLA/Kruk
AVIATION.......JLA


USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.