Area Forecast Discussion
Issued by NWS St. Louis, MO

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FXUS63 KLSX 240434

1134 PM CDT Thu Oct 23 2014

.SHORT TERM:  (Through Late Tonight)
Issued at 333 PM CDT Thu Oct 23 2014

Shortwave trough responsible for the isolated light showers
currently over the northern part of the CWA will be pushing east of
the area early this evening.  Will go dry tonight as any remaining
rain shouldn`t be more than just sprinkles.  The models show that
there will be enough low level moisture for low clouds and some fog
to develop over central and northeast Missouri as well as west
central Illinois after midnight that will last past sunrise Friday
morning.  Have added mention of patchy/areas of fog to account for
this.  Went with lows close to current dewpoints.


.LONG TERM:  (Friday through Next Thursday)
Issued at 333 PM CDT Thu Oct 23 2014

(Friday through Sunday )

Still looks like this will be a dry period with above normal
temperatures.  Weak trough will move across Missouri and Illinois
tomorrow, though moisture will be too limited in northwest flow to
provide any rain chances.  Still expect temperatures to climb above
normal as winds turn out of the southwest ahead of cold front that
will move through the area early on Saturday.  Even though the cold
front will move through early in the day, highs should be well into
the 70s on Saturday as 850mb temperatures climb into the mid teens
Celsius under mostly clear skies.  Temperatures should be similar on
Sunday as the surface high moves off the the east with clear skies.

(Monday through next Thursday)

Will keep the chance of showers and isolated thunderstorms going
over the area from Monday night into Tuesday as both the GFS and
ECMWF show a trough and an attendant cold front moving across the
region during this time frame.  While there are some minor
differences with depth and speed of the trough, do not think these
will affect timing of this system.  Highs on Monday should be once
again be well above normal ahead the cold front, but then cool down
on Tuesday with passage of the cold front.  Wednesday and Thursday
will see highs closer to normal with cold air advection behind the
front and 5-10C 850mb temperatures.



.AVIATION:  (For the 06z TAFs through 06z Friday Night)
Issued at 1106 PM CDT Thu Oct 23 2014

A band of clouds around 3000-5000 feet was moving southeastward
through the taf sites this evening. Behind it partial clearing was
leading to the development of patchy stratus and fog.  Additional
development of stratus clouds and fog can be expected late
tonight with the models depicting plenty of boundary layer
moisture. These low level clouds and fog will dissipate by late
Friday morning. A swly surface wind can be expected late tonight
and Friday.

Specifics for KSTL: Stratus clouds and fog will develop late
tonight with MVFR conditions. These low level, MVFR clouds and fog will
dissipate by late Friday morning. Light sly surface wind will veer
around to a swly direction late tonight, then back around to a
sly direction again late Friday afternoon.





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