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Area forecast discussion 
National Weather Service La Crosse WI
347 PM CDT Wednesday Sep 2 2015

Short term...(this evening through thursday)
issued at 347 PM CDT Wednesday Sep 2 2015

Main forecast concerns through the short term are on showers and
storms northeast of Interstate 94 this evening. Focus then turns to
fog tonight across north central into portions of southwest
Wisconsin.

Showers and thunderstorms are ongoing this afternoon across Clark
and Taylor counties thanks to a shortwave pushing across the region
and convergence near a boundary across these areas. Given the weak
shear in place...not expecting any widespread severe weather but
cannot rule out a strong storm or two with heavy rain being the main
threat. Storms further to west across portions of Chippewa an
Dunn counties have produced very heavy rainfall with radar
estimates of 3 to 6 inches. Will be watching these storms as they
progress east into Clark County. The showers and storms should
weaken this evening into the overnight hours as the shortwave
exit. Depending on cloud trends this evening we could see some
patchy dense fog across portions of north central Wisconsin. If
the clouds hold strong the fog may not be as thick. Something to
monitor closely tonight. A weak boundary then hangs across
portions of western into central Wisconsin Thursday into Thursday
night and may interact with a couple of weak shortwaves bringing
slight chances for showers and possibly thunderstorms. Most likely
this activity would occur southeast of the area. Otherwise...warm
and humid conditions will continue on Thursday with highs ranging
from around 80 across northern Wisconsin to the upper 80s to near
90 over northeast Iowa.

Long term...(thursday night through wednesday)
issued at 347 PM CDT Wednesday Sep 2 2015

Upper ridging then builds across the region providing warm and
mainly dry conditions. Deterministic models attempt to generate some
convection across portions of southern Wisconsin Friday into
Saturday but not really buying into those solutions with the
ridging expected. Flow aloft then turns southwest from Saturday
night into Sunday with a couple of weak shortwaves moving through
the region bringing chances for showers and thunderstorms to the
area. The stronger forcing looks to move in with a cold front late
Sunday afternoon into Sunday night and looks to bring a good
chance for showers and storms to the region. A littler early to
say whether or not there would be severe storms but its looking
like they are possible mainly across Minnesota into the western
half of Iowa Sunday afternoon into Sunday evening. We really start
to lose cape Sunday night as the storm progress eastward into the
forecast area. We will have to keep a close eye on this the next
few model runs. Cooler...more seasonable temperatures look to
return in the wake of the cold front Monday into Tuesday.

&&

Aviation...(for the 18z tafs through 18z Thursday afternoon)
issued at 1134 am CDT Wednesday Sep 2 2015

Skies will be mostly sunny this afternoon at the taf sites this
afternoon. Diurnal heating will allow the south winds to gust into
the 20 to 25 knot range. These wind gusts will continue through
03/02z.

The soundings overnight do not look favorable for dense fog at
either taf sites tonight. However there will still be a
possibility that fog may still reduce visibilities to 3 to 5
statue miles late between 03.09z and 03.13z. While dense fog does
not look favorable for the taf sites...it does look favorable for
central and north central Wisconsin.

&&

Arx watches/warnings/advisories...
WI...none.
Minnesota...none.
Iowa...none.
&&

$$

Short term...wetenkamp
long term...wetenkamp
aviation...boyne

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