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fxus63 karx 150750 
afdarx

Area forecast discussion
National Weather Service La Crosse WI
250 am CDT sun Sep 15 2019

Short term...(today and tonight)
issued at 248 am CDT sun Sep 15 2019

With the active weather overnight, today will be more of a cloud
clearing day with all the weather pushing east. Some creeks and
rivers will be rising across southwest Wisconsin and extreme
northeast Iowa /Clayton, Grant, Crawford counties/ where 1-3
inches of rain fell.

As the moisture transport in low-levels continues to veer to
westerly, convection will move east as well and by about
daybreak, the storms should be out of southwest WI. The Flash
Flood Watch will be allowed to expire at 7 am if all GOES as
planned.

Long term...(monday through saturday)
issued at 248 am CDT sun Sep 15 2019

Ridge building takes over the Great Lakes region through Tuesday
with above normal temperatures. Standardized anomalies of 1-2 for
low-level temperatures suggest warm but not record setting. Most
importantly, some drying is allowed to occur for the soils and
rivers.

Monday morning looks to be a River Valley fog morning across the
area with high pressure, clear skies, light winds through about
5kft.

The longwave trough over the western U.S. Begins to be problematic
Tuesday night as it continues to send shortwaves into the northern
plains. Southerly flow in the low-levels over much of the upper
miss valley brings a 2-3 standardized anomaly for 850/925mb
moisture, in a north-S oriented moist tongue, through Iowa/Minnesota by
Tuesday night. The large scale is not changing much and a slow
moving cold front co-located with this moist tongue shifts very
slowly across the area. While the signals are north of the area,
the GFS ensembles do suggest some higher precipitation anomalies
Wed/Thu. So, will have to keep an eye on this period for heavier
rainfall with the anomalous moisture in place. The weekend looks
active again as the western trough lifts bodily out and appears to
usher in a pattern change in the large scale.

&&

Aviation...(for the 06z tafs through 06z Sunday night)
issued at 949 PM CDT Sat Sep 14 2019

Main aviation concerns are on scattered showers and storms tonight
and MVFR to IFR stratus late tonight into Sunday morning.
Scattered showers and storms will move across the area tonight
with most of this activity staying south of the taf sites. Then
guidance is suggesting low stratus develops across the area mainly
after 09z. Ceilings are expected to fall to around 600 ft at krst
by 11z and to around 1500 ft at klse around 11z. High pressure
then builds into the area late Sunday morning into Sunday
afternoon with a return to VFR conditions.



&&

Arx watches/warnings/advisories...
WI...Flash Flood Watch until 7 am CDT this morning for wiz054-055-061.

Minnesota...none.
Iowa...Flash Flood Watch until 7 am CDT this morning for iaz008>011-018-
019-029-030.

&&

$$

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