Scientific Forecaster Discussion

Return to Local Conditions & Forecast

Without Abbreviations
With Abbreviations

Area forecast discussion...updated 
National Weather Service Green Bay WI
605 am CDT Tuesday Jul 22 2014

New information added to update section

Update...
issued at 604 am CDT Tuesday Jul 22 2014

A 555 am the main cluster of stronger storms had moved northward into
Upper Michigan. More showers and storms will likely pass over
northern Wisconsin this morning as the short wave trough and
surface low shift east over the up...however the middle level cap
edge appears to be limiting severe development southward this
am...therefore the severe watch has been canceled. Next chance of
storms may be along the cold front this afternoon and
evening...but its possible the cap will continue to limit
convection over the forecast area. A weak short wave between
500-300 mb level and some h300 diffluence may try to break the
cap in the unstable air mass later today...but not really a strong
trigger aloft.
&&

Short term...today...tonight...and Wednesday
issued at 300 am CDT Tuesday Jul 22 2014

Line of strong to severe storms ahead of short wave trough and
surface low tracking over Minnesota early this morning were moving
into far northwest Wisconsin toward north central wisconsion. Main
line of storms maintaining intensity and along the western edge of
the cap edge. Some north to south lighter convection developed
within the cap edge or just east but has not increased in
intensity. A subtle warm front was located over northern Wisconsin
with some increase in surface temperatures noted early this morning. A
severe watch was posted for north central Wisconsin to handled the
southern portion of this line working on the cap edge perimeter.
Main threat will be wind damage if storms can maintain intensity
next few hours.

Otherwise the forecast issue centers on the coverage of
additional convection today into this evening as the shortwave
trough and surface low drag a cold front over the region. Cap edge
to the south may limit convection but if storms can
develop...potential to be strong to severe again for the southeast
half of the state and areas southeast of the cold front.
Convection would likely affect parts of east central Wisconsin
through this evening before departing southeast.

Cooler drier air to filter into the region later Tuesday night
into Wednesday.

Long term...Wednesday night through Monday
issued at 300 am CDT Tuesday Jul 22 2014

No significant changes to the expected upper air pattern over the
next week. Still looking for an upper level low to undercut a
central Canada Ridge before dropping into the Great Lakes and
forming a deep eastern noam trough by the end of the period. Spread
in the models has increased a bit in the medium range as the European model (ecmwf)
has slowed down the upper low into the Great Lakes. The GFS/Gem/and
GFS ensemble mean are in better agreement and will use a blend of
these models.

Wednesday night through Thursday night...this will be a quiet period
of weather as Canadian high pressure moves across the region. The
models in previous runs have suggested a chance of precipitation due to a
push of middle-level thetae Thursday night...but they have slowed down this
thetae push while the low levels remain just as dry. So anticipate
mostly clear to clear conditions over the period. Will bump up
highs a degree or two on Thursday based on low level temperatures. Highs
in the middle to upper 70s on Thursday and lows in the 40s and 50s.

Rest of the forecast...the warm advection moves across western and
central Wisconsin on Friday and into eastern Wisconsin Friday
night. As a result...chances of precipitation will improve from west to
east during this time. Then a trough will move across the region on
Saturday which will keep showers and isolated storms in the
forecast. Unsettled conditions will continue into early next week
as the upper low finally drops through the region.
&&

Aviation...for 12z taf issuance
issued at 547 am CDT Tuesday Jul 22 2014

Areas MVFR ceilings associated with showers and storms
were passing over parts of central and north central this morning.
Showers and storms will be more focused over northern Wisconsin
for the morning hours...otherwise convection later today into
tonight will likely focus along or ahead of a cold front dropping
south over the state today into this evening.

The taf for Oshkosh witmann regional Airport is now being
produced by the National Weather Service in Green Bay in support
of the eaa air venture.
&&

Marine...
issued at 300 am CDT Tuesday Jul 22 2014

Strong and gusty SW winds to lead to small craft
conditions on Tuesday. High waves and strong currents will
continue along the Lake Michigan coast.
&&

Grb watches/warnings/advisories...
beach hazards statement from 10 am CDT this morning through this
evening for wiz022-040-050.
&&

$$

Update.........Tdh
short term.....Tdh
long term......mpc
aviation.......tdh
marine.........Tdh

National Weather Service Glossary of Abbreviations