Area Forecast Discussion
Issued by NWS St. Louis, MO

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FXUS63 KLSX 050821

321 AM CDT Tue May 5 2015

.SHORT TERM:  (Through Late This Afternoon)
Issued at 320 AM CDT Tue May 5 2015

Ongoing activity over far northern portions of forecast area to
continue diminishing this morning as front shifts a bit further
north, but with front so close could still see isolated activity.
Kept slight chance pops going for this area. Otherwise, majority
of region will be dry today though some isolated activity not out
of the question for areas along and south of I-70 where there is
no cap, decent CAPE and some weak surface moisture convergence. As
for high temps, low to mid 80s expected.


.LONG TERM:  (Tonight through Monday)
Issued at 320 AM CDT Tue May 5 2015

By tonight, frontal boundary will be well north of forecast area,
with dry and mild conditions persisting overnight with lows in the
low 60s.

On Wednesday another round of activity to fire up on periphery of
surface ridge affecting central/northeast MO as well as west central
IL, before diminishing after sunset Wednesday night.

By Thursday, surface ridge shifts further to the east allowing
weather system to move closer to region. Plenty of low level
moisture to stream in with surface dewpts in the 60s and several
shortwaves slide through region as frontal boundary slowly sinks
south into forecast area. So will see several rounds of showers and
thunderstorms through the last part of the work week and into next
weekend. Some differences on timing and placement of system among
the extended models, so just kept with a blend of the solutions for
now. Highs will be in the 70s/80s through the period with lows in
the 60s.


.AVIATION:  (For the 06z TAFs through 06z Tuesday Night)
Issued at 1123 PM CDT Mon May 4 2015

Primary focus remains on thunderstorm activity over central into
northern Missouri and west central Illinois. Looks like the best
chances for storms will be north of our forecast area in Iowa and
Illinois, but isolated to scattered thunderstorms will continue to
be possible through 08-10Z this morning generally along and
northwest of a line from KVER to KPPQ. VFR conditions are expected
to prevail outside of thunderstorms. South-southwest flow will
increase to around 10kts Tuesday afternoon with gusts to around
20kts. There is a slight chance for storms again in the afternoon,
but probability is too low to mention in the terminal forecasts at
this time.

Specifics for KSTL:

VFR flight conditions are expected to continue to prevail at
Lambert for the rest of the night and through Tuesday. Think the
storms back over central Missouri will stay well away from the
terminal for the rest of the night. There is a slight chance of
thunderstorms for Tuesday afternoon, but the probability is too
low to mention in the terminal forecast at this time. Southwest
flow will increase to around 10kts with gusts to around 20kts
during the afternoon. Think the prevailing direction will stay
just south of 210 degrees, but it may temporarily veer past 210 at



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