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Area forecast discussion 
National Weather Service Green Bay WI
109 PM CDT Wednesday Oct 7 2015

Updated aviation portion for 18z taf issuance

Short Thursday
issued at 314 am CDT Wednesday Oct 7 2015

High pressure building in behind a departing cold front will bring
mostly sunny skies with cooler temperatures across northeast
Wisconsin. Highs will range from the upper 50s across north
central the lower to middle 60s across central and
east central Wisconsin.

Meanwhile...a quick moving low pressure system...seen on water
vapor imagery over southern prognosticated to track through
the western Great Lakes later tonight and into Thursday. Recent
nwp model runs have slowed the system down a bit...with the
heaviest rain not expected until late tonight and into early
Thursday. Given the model consensus will tighten up probability of precipitation a bit
this run and focus the highest probability of precipitation on when the heaviest rain is

The system itself will have decent precipitable waters of 1 to 1.3 inches along
with good forcing as the strong middle level shortwave tracks through
the western Great Lakes coincident with the right entrance region
of an 80 to 90 knot upper level jet and a 40 to 50 knot low level
jet. In addition there will be some elevated instability with
MUCAPE values of a few hundred j/kg...which could bring some
rumbles of thunder with the showers at times. The forcing and
moisture available to the system will bring the Prospect of
moderate and heavy rainfall to northeast Wisconsin late tonight
and into Thursday...with the best chances across northern
Wisconsin coincident with the best middle level frontogenesis and
closer to the system dynamics.

Abundant cloud cover moving in from the west will keep lows in the
40s tonight...while highs Thursday will range from the middle 50s
across the far north...with upper 60s across the south ahead of
the cold front.

Long term...Thursday night through Tuesday
issued at 314 am CDT Wednesday Oct 7 2015

Showers are expected to linger into Thursday night...especially
in far north central and eastern Wisconsin. But surface high
pressure building into the region and upper level flow becoming
more zonal should lead to dry conditions with a warming trend from
Friday through the weekend. Highs on Friday should be near
normal...warming to 10 to 15 degrees above normal by Sunday.

After that a low pressure system moving across Canada will drag a
cold front through Wisconsin Sunday night/early Monday...followed
by an upper level short wave passing across the state. There
could be some showers Monday into Tuesday but have mostly slight
chance probability of precipitation going for now. Temperatures should cool off a bit
during the early part of the work week...but they will still be
several degrees warmer than normal.

Aviation...for 18z taf issuance
issued at 108 PM CDT Wednesday Oct 7 2015

Hi pressure is expected to move over the Great Lakes this afternoon
into the evening hours before shifting off to the east. While most
locations to remain VFR with hi clouds into the Evening...Lake
clouds may briefly bring MVFR ceilings to the mtw taf site. A more
general increase in clouds is forecast for late evening/overnight as a
clipper-type area of low pressure/associated cold front sweeps into the upper
MS valley. Anticipate the leading edge of shower activity to reach
central WI late tonight with ceilings/visibilities dropping into the MVFR range.
As this system crosses the region on Thursday (mainly during the
morning hours)...shwrs/slgt chance of thunderstorms to push through the area.
Ceilings/visibilities to reside in the IFR/MVFR range in the morning before
primarily sitting in the MVFR range in the afternoon as cold air advection takes

Grb watches/warnings/advisories...


Short term.....Kurimski

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