Area Forecast Discussion
Issued by NWS St. Louis, MO

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FXUS63 KLSX 212028

Area Forecast Discussion
National Weather Service Saint Louis MO
328 PM CDT Wed Jun 21 2017

.SHORT TERM...  (Through Late Thursday Afternoon)
Issued at 323 PM CDT Wed Jun 21 2017

It looks like tonight should be a rather uneventful night. The weak
front which sagged from northern MO into south central IL has begun
to lift back northward. A few short-lived cells developed along the
front in Montgomery and Fayette Counties earlier, but they have
since dissipated. There could still be an isolated shower or storm
into the late afternoon along the boundary where an axis of
diurnally enhanced instability resides.

For most of tonight we will be watching an increase in high clouds
from the south associated with TS Cindy. In the predawn hours, the
low level flow will begin veering in the gradient region from
eastern AR/MS into southeast MO well to the east Cindy. This will
result in deeper moisture transport into southeast MO and possibly a
few showers. Present indications are Cindy will move in the vicinity
of the TX/LA border on Thursday. The increase in south to southwest
flow to the east of the center will continue to transport
deeper/tropical moisture northward into the area. The
moisture/clouds should result in cooler temps on Thursday,
especially the southern 2/3rd of the CWA. The best threat of any
precipitation should be across southeast MO and southern IL
coincident with the deeper moisture and also a north-northeast
lifting vort max within the south/southwest mid-upper flow to the
east of Cindy.


.LONG TERM...  (Thursday Night through Next Wednesday)
Issued at 323 PM CDT Wed Jun 21 2017

Showers and storms will end from northwest to southeast as the cold
front pushes through the area on Friday. The front should clear
the area by Friday night. High pressure at the surface from the
northern high plains will push into the area. In the upper levels,
the area will be under northwest flow with a series of weak short
waves pushing through the area. A few of the models attempt to
kick off an isolated shower or thunderstorm mainly during the
afternoon and evening Sunday and Monday, while others are
completely dry. The confidence level that any precipitation will
materialize is very low at this time and likely will remain dry.

 After a period of below climatological normal temperatures will
moderate to normal values Wednesday ahead of the next storm system
organizing in the plains. This will bring a chance of showers and
thunderstorms to the area Wednesday night into north central



.AVIATION...  (For the 18z TAFs through 18z Thursday Afternoon)
Issued at 1244 PM CDT Wed Jun 21 2017

A weak quasi-stationary front currently stretches from far
northwest MO into south central IL. This front will retreat back
northward this afternoon, and may be the focus for a few
thunderstorms in IL. Any activity should remain removed from any
of the terminals. VFR flight conditions are expected through the
forecast period with a big surge in cloud cover on Thursday
morning across eastern MO and southwest IL.


VFR flight conditions are expected through the forecast period
with a big surge in cloud cover on Thursday morning.





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