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Area forecast discussion 
National Weather Service Green Bay WI
1204 PM CDT Friday Oct 9 2015

Updated aviation portion for 18z taf issuance

Short Saturday
issued at 300 am CDT Friday Oct 9 2015

Main concern early in the forecast is the presence of low clouds
across the County Warning Area. There is a battle between lingering low level
moisture and dry air advection with an approaching high pressure
system coming in from the west. Infrared satellite imagery shows the dry
air is quickly winning out with multiple openings in the
previously solid deck of low clouds across the western Great Lakes
region. The break up of the clouds will also bring an end to the
drizzle this morning.

The clearing skies will give way to some sunshine this morning
across the western Great Lakes...however this should be short
lived as cumulus rule values of -4 to -6 should result in fair weather
cumulus clouds across the area later this morning. With a cool
airmass in place daytime highs are only expected to get into the
middle to upper 50s.

With the loss of daytime heating tonight skies will become mostly
clear with light winds underneath a ridge of high pressure. Given
the cool airmass overhead...coupled with light winds and mostly
clear skies...continued trend of going cooler than MOS with
temperatures overnight. Lows are expected to range from the middle
30s across north central Wisconsin...with upper 30s to lower 40s
across central and east central Wisconsin.

The ridge will sink south on Saturday...allowing return flow on
southwesterly winds across the western Great Lakes. Mostly sunny
skies and warm air advection will bring daytime highs back to the
lower to middle 60s. However unlike today...cumulus rule values are not
indicative of much in the way of cumulus development.

Long term...Saturday night through Thursday
issued at 300 am CDT Friday Oct 9 2015

The main concerns during this part of the forecast are timing and
location of rain associated with a passing upper trough and
surface cold front.

Models had the upper trough and the cold front passing through the
state on Monday so generally kept rain chances confined to
Monday. Most of the models depicted the heaviest rainfall well
north of the forecast area...closer to the stronger upper level
support. This system is not expected to pick up any Gulf moisture
as it probability of precipitation and quantitative precipitation forecast are limited due to the limited
moisture. Kept the solution produced by the model blend...which
had chance probability of precipitation in north central Wisconsin on Monday...with
slight chance probability of precipitation for the rest of the area...then just some
slight chance probability of precipitation in the north on Monday night. After
that...broad cyclonic flow across the region produced nothing more
than sporadic slight chance probability of precipitation on the fringes of the forecast

High temperatures should be around 15 degrees above normal on
Sunday and 5 to 10 degrees warmer than normal on Monday...before
the cold front cools them off to near normal for the rest of the
work week.

Aviation...for 18z taf issuance
issued at 1203 PM CDT Friday Oct 9 2015

Cool air aloft and daytime heating have allowed low-end VFR cumulus
field to develop across NE WI this afternoon. Expect ceilings to be
mainly in the 3500-4500 feet range before dissipating around sunset.
Gusty north-northwest winds will gradually subside late this afternoon into
early evening as an area of hi pressure moves into the region. Other
than some passing hi clouds tonight into Sat...VFR conditions to be
the rule. We do anticipate winds to pick up on Sat as NE WI gets
behind the departed surface hi. SW winds of 15 to 20 kts are expected
with gusts around 25 kts.

issued at 300 am CDT Friday Oct 9 2015

Gusty north to northwest winds behind a low pressure system and
associated cold front are expected today which will produce gusty
winds and large waves on the Bay and lake. High pressure moving in
from the west will cause winds and waves to subside later today
and into the overnight hours. At this time all small craft
headlines will remain as is and expire on time.

As the high sinks south...gusty southwest winds will cause winds
and waves to once again build across the western Great Lakes
Saturday and into Sunday. Small craft advisories will likely once
again be needed for the marine areas during the weekend.

Grb watches/warnings/advisories...


Short term.....Kurimski

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