Area Forecast Discussion
Issued by NWS St. Louis, MO

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FXUS63 KLSX 221110

610 AM CDT Tue Jul 22 2014

.SHORT TERM:  (Through Late This Afternoon)
Issued at 348 AM CDT Tue Jul 22 2014

During the day today the upper ridge will remain in place with
surface temperatures expected to warm up into the low to mid 90s.
Low level moisture continues to increase as well, so will see heat
indicies between 100 and 105 for central and northeast MO as well as
west central IL.


.LONG TERM:  (Tonight through Monday)
Issued at 348 AM CDT Tue Jul 22 2014

In the meantime, cold front associated with next weather system
to move into far northern portions of MO by 00z Wednesday. Short
term models begin to develop complex along frontal boundary around
this time and track it to the south and southeast through forecast
area tonight. Some differences on timing and coverage between the
models, so went with a blend and increased pops to likely late
this evening and into the overnight hours as it moves through.
Despite all of the instability and moisture, some concern about
mid level capping, but confident cap will weaken sufficiently to
allow storm development. With decent capes, moisture and
instability, SPC has placed northern portions of forecast area in
a slight risk for tonight with main threats being large hail and
damaging winds.

System to continue tracking south through southern portions of
forecast area Wednesday morning, before tapering off Wednesday
afternoon. As for highs on Wednesday, will range from the low 80s
far north to around 90 far south.

By Wednesday night, surface ridge begins to build in and bring in
drier and cooler weather for the last half of the work week. Highs
on Thursday will be in the upper 70s to mid 80s.

Surface ridge to move off to the east by Friday with a warm front
developing across region with elevated convection possible for
portions of forecast area Friday and Friday night. Then as main cold
front moves into region on Saturday, will see additional rounds of
storms through Sunday night before system exits region on Monday.
Temperatures to moderate through the weekend once again.



.AVIATION:  (For the 12z TAFs through 12z Wednesday Morning)
Issued at 604 AM CDT Tue Jul 22 2014

VFR conditions are anticipated today with southwest wind around
10KT. Cold front will move across the area this evening and
overnight with thunderstorms expected to develop along and ahead
of the front. Conditions could dip into MVFR range with
thunderstorms, otherwise a wind shift to the northwest will occur
with the front.

Specifics for KSTL:
Expect thunderstorm complex ahead of the cold front will move
across the terminal around 06Z with a temporary reduction in
visibility, a wind shift to the northwest and potential for some
gusts to 25KT. Conditions will rapidly improve on Wednesday with
north wind.





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