Area Forecast Discussion
Issued by NWS St. Louis, MO

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FXUS63 KLSX 222000

300 PM CDT Tue Apr 22 2014

.SHORT TERM:  (Through Late Tonight)
Issued at 259 PM CDT Tue Apr 22 2014

Surface ridge to move off to the east tonight allowing southerly
winds to return to the region by Wednesday. In the meantime, clear
skies and light north winds to prevail tonight. Lows will drop into
the low to mid 40s.


.LONG TERM:  (Wednesday through Next Tuesday)
Issued at 259 PM CDT Tue Apr 22 2014

On Wednesday, mid and high clouds will be on the increase as next
weather system approaches region. With southeast to south winds
temperatures to warm up into the mid 60s to mid 70s.

As for precipitation chances, feel that there is a lot of dry air to
overcome, so best chances for showers and thunderstorms will be on
Thursday as cold front swings through region. Not a lot of
instability with this system with highest capes, around 500 j/kg,
especially along and south of I-70. Activity to exit area Thursday
evening. Highs on Thursday will depend on cloud cover, precipitation
and timing of cold front. For now have mid 60s to low 70s.

Not a lot of caa behind this system and will see a secondary frontal
boundary slide south through region on Friday stalling out well
south of forecast area. Do not anticipate any precipitation with
this boundary, but will become the focus of activity later in the
weekend and into early next week for our area. Highs on Friday will
be in the 70s.

Extended models still have timing and placement issues with
activity. For now have showers and thunderstorms developing across
western portions of forecast area on Saturday and spreading east
Saturday night. The activity will linger through the rest of the
weekend and into early next week. Looks like best chances will be
Sunday night and Monday.


.AVIATION:  (For the 18z TAFs through 18z Wednesday Afternoon)
Issued at 1057 AM CDT Tue Apr 22 2014

Surface ridge extending from MN s-sw into OK will move eastward
through our area. The n-nwly surface wind will weaken this evening
and veer around to an e-nely direction. The wind will strengthen on
Wednesday from a sely direction as the surface ridge axis shifts
east of our area. There may be some high level clouds late
tonight, then mid level clouds will develop and move eastward
through northeast MO and west central IL on Wednesday due to
strong low-mid level warm air advection.

Specifics for KSTL: N-nwly surface wind will weaken this evening
and become light late tonight. The wind will increase again to
around 10 kts Wednesday afternoon from a sely direction. Just
some high level clouds late tonight, then mid level clouds on



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