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Area forecast discussion
National Weather Service La Crosse WI
333 PM CDT Mon Oct 21 2019

Short term...(this evening through tuesday)
issued at 332 PM CDT Mon Oct 21 2019

At 3 PM, a deepening surface low was located over the Twin Cities.
Convective available potential energy have climbed up to 750 j/kg across northeast Iowa,
southeast Minnesota, and west-central and north-central
Wisconsin. In addition, the rap has wind shear climbing up to 45
knots across northeast Iowa and southeast Minnesota late this
afternoon and early evening. In addition, the NST parameter moves
into northeast Iowa and southeast Minnesota just ahead of the
deformation band. While it is not the most favorable severe
weather setup, it is something that should be watched closely
between 21.23z to 22.03z.

From late tonight into Tuesday, the BUFKIT soundings continue to
show that we will mix up to 800 mb. In addition, the 950 to 850 mb
lapse rates will climb above 8 c/km. This will result in sustained
winds of 20 to 30 mph with wind gusts up to 45 mph. Due to this, a
Wind Advisory is in effect from 4 am to 7 PM Tuesday west of the
Mississippi River and from 7 am to 7 PM Tuesday south of
Interstate 94 in western Wisconsin.

Long term...(tuesday night through monday)
issued at 332 PM CDT Mon Oct 21 2019

From Wednesday into Wednesday evening, a low pressure system will
move quickly east southeast across Iowa. This system will produce
light rain along and south of Interstate 90. This rain may
briefly mix with some snow in the morning and evening, but no
accumulations are expected. Rainfall amounts will be up to a
tenth of an inch.

The next chance of rain looks to be on Sunday, but confidence is
really low due to a wide range of solutions.


Aviation...(for the 18z tafs through 18z Tuesday afternoon)
issued at 1250 PM CDT Mon Oct 21 2019

Rain showers exited both sites this early afternoon which has led
to clearing and VFR conditions. For krst, there is a chance for
MVFR ceilings this afternoon at times. Leading into this evening
and through Tuesday morning, rain shower chances return as the
low tracks to the northeast and rain wraps around the system.
IFR to MVFR ceilings are likely with visibility reductions
expected with the associated heavier rain showers. The pressure
gradient tightens with winds shifting westerly tonight, gusting
over 30 kts by early Tuesday.


issued at 332 PM CDT Mon Oct 21 2019

Both La Crosse and Rochester are very close to setting daily
precipitation records for October 21st.

La Crosse has received 1.56 inches, so far. Their record is 1.60
inches in 2009.

Rochester has received 1.33 inches, so far. Their record is 1.57
inches in 2009.

The La Crosse precipitation total climbed above 40 inches (40.40
inches) for the year. This is the 13th time that this has occurred
since 1873. The last 4 years are among the 14 wettest (2016 -
wettest, 2017 - 14th wettest, and 2018 - 5th wettest).

The Rochester precipitation total climbed above 50 inches (50.87
inches) for the first time in a calendar year. 8 out of the 15
wettest years at Rochester have occurred since 2004. All 5 of the
wettest years have occurred since 2007.


Arx watches/warnings/advisories...
WI...Wind Advisory from 7 am to 7 PM CDT Tuesday for wiz032>034-

Minnesota...Wind Advisory from 4 am to 7 PM CDT Tuesday for mnz079-086>088-

Iowa...Wind Advisory from 4 am to 7 PM CDT Tuesday for iaz008>011-018-



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