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000
FXUS63 KARX 171830
AFDARX

Area Forecast Discussion
National Weather Service La Crosse WI
130 PM CDT Sun Sep 17 2017

.SYNOPSIS...
Issued at 130 PM CDT Sun Sep 17 2017

High pressure moving east across the area this afternoon producing
mostly sunny skies with cooler/pleasant temperatures ranging from
the middle 60s to a few lower 70s.

&&

.SHORT TERM...(This evening through Monday)
Issued at 130 PM CDT Sun Sep 17 2017

High pressure will slip off to the east tonight as a mid-level
trough ejects northeast out of the Central Plains. Moderate
isentropic lift and 850-700mb moisture transport will increase
altocumulus cloud cover across the area after midnight with a few
showers possible west of the Mississippi River by sunrise.
Otherwise, plan on lows tonight ranging from the middle 40s in the
sand country of central WI to the upper 40s/lower 50s elsewhere.

Scattered showers will then spread northeast across the area for
Monday as that mid-level trough tracks northeast into the Upper
Mississippi River Valley. A few isolated rumbles of thunder are
possible across northeast IA into far southwest WI where slight
steeper mid-level laps rates will reside. Scattered showers/cloud
cover will keep temperatures on the cooler side with highs in the
60s to near 70.

.LONG TERM...(Monday night through Sunday)
Issued at 130 PM CDT Sun Sep 17 2017

Scattered showers will linger into Monday evening, tapering off
after midnight as that mid-level trough exits east.

Although there is fairly broad/weak warm air advection and
isentropic lift ahead of low pressure moving into the Northern
Plains, NAM bufkit sounding keeps things dry. Will keep dry for now
based on this. Otherwise, looks like temperatures will be right
around seasonal norms with readings in the 70s.

Shower and thunderstorms chances will be on the increase Tuesday
night into Wednesday as that area of low pressure and cold front
move east into the region. May have to keep an eye out for a severe
threat on Wednesday as there will be ample Bulk Shear and CAPE.
Otherwise, expecting highs Wednesday in the middle 70s to the lower
80s.

Models are indicating a blocking pattern setting up across the
central/eastern CONUS for Thursday into Sunday. A ridge slowly
amplifies over the Great Lake region while a trough deepens out
west. Our area will looks to be on the western edge of the ridge
which makes us susceptible to southwest flow aloft out of the
Rockies and periodic shower/thunderstorm chances. This pattern will
also keep us warmer than normal.

&&

.AVIATION...(For the 18Z TAFS through 18Z Monday afternoon)
Issued at 1217 PM CDT Sun Sep 17 2017

A large area of high pressure centered over eastern Nebraska late
this morning, will move east across the area into the Great Lakes
through Monday morning. This will provide VFR conditions through
the period to both airports. However, a short wave trough will
move out of the Central Plains late tonight and toward the area
Monday morning. The forcing ahead of this wave will cause a mid
level ceiling to spread over both airports overnight. Showers
associated with this feature should move in Monday morning and
could have a chance to impact KRST but stay west of KLSE.
Confidence on the timing or areal coverage of the showers is too
low at this point to include a VCSH at the end of the forecast,
but this may be needed with later forecasts for both airports.

&&

.ARX WATCHES/WARNINGS/ADVISORIES...
WI...None.
MN...None.
IA...None.
&&

$$

SYNOPSIS...DAS
SHORT TERM...DAS
LONG TERM...DAS
AVIATION...04