Area Forecast Discussion
Issued by NWS Green Bay, WI

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FXUS63 KGRB 280826

Area Forecast Discussion
National Weather Service Green Bay WI
326 AM CDT FRI OCT 28 2016

Forecast discussion for routine afternoon forecast issuance

.SHORT TERM...Today...Tonight...and Saturday
Issued at 326 AM CDT Fri Oct 28 2016

Southerly winds will increase precipitously across the region
today with return flow on the backside of a departing high and
ahead of a low pressure system approaching from the west. Winds
today will gust to 25 to 35 mph...with a few gusts of 40 to 45 mph
possible across Door County. Satellite imagery shows quite a bit
of low level moisture in the form of clouds across the western
Great Lakes and upper Mississippi Valley. This moisture will not
go anywhere as model soundings show a steep low level inversion
which should trap this moisture and maintain low clouds across the
cwa. The inversion will also keep wind gusts in check, as winds
just a few thousand feet above the surface reach 60 knots or
greater. Despite the inversion and abundant cloud cover, warm air
advection will allow daytime highs to soar to well above normal
levels with temperatures ranging from the middle to upper 50s
across the north, with lower 60s across the south.

The aforementioned low will track to the north later this
afternoon and this evening, bringing the chance for light showers
or drizzle to the northeast corner of the cwa. The attendant cold
front from this system will also track through, however there
isn`t much cold air associated with this front as overnight lows
stay in the upper 40s across the north, with low to mid 50s
expected across the south.

A mid level trough will track through the western Great Lakes on
Saturday, bringing the chance for showers to the area Saturday
afternoon as the cold front passing through tonight stalls across
the southern Great Lakes. Highs Saturday will still be above
normal as temperatures range from the lower to middle 50s across
the north, with highs around 60 further south.

.LONG TERM...Saturday Night Through Thursday
Issued at 326 AM CDT Fri Oct 28 2016

The latest GFS ensemble mean continues to indicate that above normal
heights will prevail across the region for much of this period.
There will be a few chances of precip, but the Gulf of Mexico will
be shut off, so any precip will be on the lighter side.  The
operational models are in modest agreement tonight, so will blend
the ecwmf and gfs for much of this forecast.

Saturday night through Sunday night...A shallow polar cold front
will be dropping south across the region on Saturday night. Upper
divergence in the right rear quad of a jet streak and mid-level fgen
will support light precip chances continuing across much of the
area, highest over central and east-central WI.  This light rainfall
will exit late Saturday night and guidance indicates that some
clearing will occur early Sunday morning before diurnal cu pops up
by midday.  While cu fades late Sunday afternoon, should see mid and
high clouds increase again late Sunday night ahead of the next
system.  Think the dry air will hold out though, so will leave a
precip threat out of the forecast.

Rest of the forecast...Low pressure will travel northeast across the
northern Plains on Monday and Lake Superior on Monday night.  Most
if not all of Wisconsin will reside in the warm sector, so should
see a breezy and mild day with a small chance of showers over
northern WI in the warm advection regime.  Because of the abundance
of dry air in the mid-levels, conditions look dry elsewhere despite
a cold front advancing across the region on Monday night.  Breezy
conditions will persist into Tuesday, but high pressure will keep
the weather dry.  The next chance of rain looks to occur on Wed and
Wed nite as a system moves northeast over the southern Great Lakes.
As for temps, no sign of any significant cold air intruding into the
Great Lakes through the first week of November.

.AVIATION...for 06Z TAF Issuance
Issued at 959 PM CDT Thu Oct 27 2016

Predominantly MVFR clouds expected overnight into Friday morning.
Some improvement to lower end VFR clouds possible Friday afternoon,
but pockets of MVFR clouds may continue to linger, especially
over northern Wisconsin. South winds will be on the increase
Friday afternoon, with gusts to near 30 knots possible through
Friday evening. Strong winds just above the surface Friday night may
produce LLWS wind shear conditions as surface winds subside.

Issued at 326 AM CDT Fri Oct 28 2016

Winds and waves will increase today and tonight as a low pressure
system tracks across the northern Great Lakes and upper level
winds increase considerably. Wind gusts are expected to reach gale
force this afternoon through this evening.

Another low pressure system will bring high winds and waves which
will be hazardous to small craft to the western Great Lakes
Monday and Monday night. A few gusts could approach Gale force
during the day on Monday.



SHORT TERM.....Kurimski
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