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Area forecast discussion
National Weather Service La Crosse WI
613 am CDT Tue Jul 23 2019

Short term...(today through tonight)
issued at 247 am CDT Tue Jul 23 2019

With amplified upper ridge axis centered over rockies, area remains
in northwest flow. Watching short wave trough drop across western
Great Lakes early this morning that triggered some clouds and
convection, but that should continue to exit the area. Also keeping
tabs on possible patchy early morning fog, but given weak northwest
winds and dry airmass, thinking that will be limited.

Fairly quiet day on tap once again, but some hints in mesoscale
models that another weak wave and afternoon lapse rates could lead
to regeneration of scattered showers, mainly east of Interstate 94
in Wisconsin. Coverage should remain very spotty, and any convection
that does form will dissipate going into what looks like another
quiet night.

Long term...(wednesday through monday)
issued at 247 am CDT Tue Jul 23 2019

Later periods can be summarized by flow becoming somewhat more zonal
and series of short wave troughs passing through creating occasional
rain and storm threats.

Some model discrepancies exist for Wednesday with possibility of
yet another weak impulse in flow. 23.00z GFS run is most robust
with afternoon convection but other models far more contained,
which is preferred. Introduced small rain chances to blend with
possibility across eastern Wisconsin but again, looks very

Stronger synoptic system will top deamplifying ridge going into
Thursday night which will lead to forcing ahead of associated front.
Will see some instability and increasing moisture transport ahead
and along this feature going into Friday, but should remain
progressive in nature. Could be just enough instability and shear
for some strong storms but lower confidence on details this far out
and southward extent from main wave.

Rain threats after that, including the weekend, will depend on where
front lays up. Lack of any forcing Saturday and expected warming
conditions could lead to a relatively quiet and warm day, but
boundary could also lead to small convective development too so will
have to watch how this plays out. Another passing short wave by
Sunday will focus a greater storm threat, especially further north.
This system could sweep aforementioned front through and out of the
area to start next week.


Aviation...(for the 12z tafs through 12z Wednesday morning)
issued at 612 am CDT Tue Jul 23 2019

VFR conditions will continue as high pressure sits over the
region. Expect to see few to sct diurnal cumulus develop towards
midday, more prevalent over eastern WI where a weak disturbance
will trigger scattered pop up showers and storms. These are
expected to stay well east of lse and diminish around sunset. Will
then see an increase in mid-high level clouds heading into
tonight. Northwest winds will turn a tad gusty this afternoon,
diminishing this evening.


Arx watches/warnings/advisories...

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