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000
FXUS63 KARX 240700
AFDARX

Area Forecast Discussion
National Weather Service La Crosse WI
200 AM CDT Sat Jul 24 2021

.SHORT TERM...(Today through Sunday Night)
Issued at 200 AM CDT Sat Jul 24 2021

GOES-East showing a mid-level trough pushing eastward across the
eastern Dakota/western MN. At the surface, a weak surface cold front
extended from western lake Superior through southwest MN. Radar was
showing scattered convection along the frontal boundary/ahead of the
mid-level trough.

The trough and surface front continues to push southeast into our
area this morning and through the day, exiting by late this
afternoon. There will be a decent cap in place, keeping the
convection elevated in nature and lacking shear -limiting severe
potential. Bulk of the showers/storms/resulting rainfall looks to be
north of I-90. Also doesn`t show promise for a substantial rain,
generally a tenth to a half inch expected...but could see a pocket
or two of some heavier amount potential given the high precipitable
water values/humid airmass in place. Again, not expecting much for
severe potential given weak shear but will have to keep an eye out
for a stronger cell or two with small hail and localized downburst
wind potential. Otherwise, won`t see a relief in the humidity
despite the frontal passage as drier air lags behind. Lingering
muggy airmass and highs topping off in the mid 80s to lower 90s will
produce heat indices in the 90 to 100 range...highest over portions
of northeast IA into far southwest WI.

Sunday will be another very warm day but should see a marked
difference in humidity levels as drier air filters in. Will likely
see hazy skies again though as wildfires out west and over portions
of Canada continue to produce smoke aloft. Otherwise, plan on highs
ranging from the mid-80s to lower 90s.

Enjoy the drier air Sunday as dew points start the creep upwards
again Sunday night as a warm front pushes northward out of the
Plains. Could also see a few showers/storms along this front but
appears they will stay just west of our area.

.LONG TERM...(Monday through Friday)
Issued at 200 AM CDT Sat Jul 24 2021

Upper level ridge amplification across the Intermountain West and
Plains will keep us in northwest flow aloft during this period. As
such, we will likely see intermittent shower/storm chances along
with very warm and rather muggy conditions.

&&

.AVIATION...(For the 06Z TAFS through 06Z Saturday night)
Issued at 1053 PM CDT Fri Jul 23 2021

Convection has developed this evening over South Dakota along a
surface trough ahead of an incoming short wave trough. All the
hi-res meso-scale models suggest this activity will hold together
overnight as it moves east toward the area. There should be some
weakening of the activity as it moves past the best instability
gradient and into the mid-level warm air in place over the region.
This should result in mainly showers with some embedded
thunderstorms probably impacting both airports, with the chances
a little bit better for KRST than KLSE. Will throw in a short
tempo group with some MVFR conditions at KRST while holding with
VCTS and VFR at KLSE for now. Once this activity moves past in the
morning, VFR conditions should return and then remain through
Saturday evening.

&&

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

$$

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