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Area forecast discussion
National Weather Service La Crosse WI
531 am CDT Fri Aug 23 2019

Short term...(today through sunday)
issued at 256 am CDT Fri Aug 23 2019

Quiet stretch of weather continues through the weekend, courtesy of
broad low level ridging drifting through southern Ontario but firmly
maintaining drier air in place across the area. Really not much in
the way of big-time forecast concerns, with pesky mid clouds likely
to hang around at times today, stuck within a very weak 850-700mb
flow regime, while some diurnal cumulus also develops each
afternoon. Currently also seeing a touch of fog out there in some of
the river valleys, and that will again develop tonight, though
perhaps relegated mainly to the deeper river valleys (kickapoo,
wisconsin) given hints of 10-15 knots of flow developing just off
the surface after 03z. Otherwise, temperatures remain comfortable
with daytime highs mainly in the 70s and lows in the 50s, while the
typical cooler spots dip into the 40s. As hinted at for several days
now, just too much dry air in place up through Sunday to support any
real precipitation risk, so along the lines of earlier shifts, will
maintain dry conditions right on through Sunday evening.

Long term...(sunday night through thursday)
issued at 256 am CDT Fri Aug 23 2019

High pressure still looks to gradually lose its influence on the
area Sunday night into Monday, as a series of shortwaves within a
broader upper trough advance from the northern rockies into the
upper Midwest. One such wave forecast by majority of medium range
guidance to lift from northern Missouri up across Lake Michigan into
Monday, while a stronger mid level trough axis works in from the
west by Monday evening, driving a cold front through the area. That
setup should support our best risk for showers and a few storms,
though to be honest, overall instability appears lacking per cooler
surface temperatures and weak low/mid level lapse rates in place.
Additional smaller shower chances appear warranted Tuesday into
Wednesday beneath broad thermal troughing, with overall
temperatures holding roughly near normal by late August standards,
perhaps a little cooler at times pending coverage of any
rainfall.

&&

Aviation...(for the 12z tafs through 12z Saturday morning)
issued at 530 am CDT Fri Aug 23 2019

High pressure will provide VFR conditions today through tonight.
Look for prevailing winds less than 10kt from the east/southeast.
Expecting some River Valley fog early Saturday morning but
thinking not enough to impact klse at this time.

&&

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

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