Area Forecast Discussion
Issued by NWS St. Louis, MO

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FXUS63 KLSX 242250

550 PM CDT Fri Oct 24 2014

.SHORT TERM:  (Tonight through Sunday)
Issued at 332 PM CDT Fri Oct 24 2014

The last vestiges of this morning`s low clouds and fog is finally
dissipating.  However, clearing sky and light wind combined with
relatively high dewpoints in the mid and upper 50s tonight will
likely produce more fog.  A weak trof of low pressure now moving
through eastern Nebraska will also drop into the area providing a
little lift and convergence but not much of an increase in wind.
Unsure how low to go at this time, but at least patchy fog looks
likely with more widespread fog in northeast MO/west central IL.

Fog will likely linger into the daytime hours of Saturday morning.
A lot of uncertainty as to how long...but at least through 14-15Z
seems likely.  The trof is expected to come to a halt Saturday
afternoon/evening near the MO/AR border then begin lifting back to
the north as a warm front as warm advection begins ahead of the next
system.  The warm front continues lifting north Sunday and decent
mixing should give us temperatures well above normal.  MOS
temperatures through Sunday look pretty reasonable so have followed
them closely.


.LONG TERM: (Sunday Night through Next Friday)
Issued at 344 PM CDT Fri Oct 24 2014

Sunday night into Monday the next strong shortwave moves from the
Rockies into the Great Plains.  Strong warm advection should keep
temperatures pretty mild...more summer-like in fact...into Monday
afternoon.  As the surface cold front associated with the shortwave
approaches the area Monday night, expect scattered showers and
possibly a few thunderstorms to affect the area.  Kept PoPs in the
high chance/low likely range as the front moves through the area
late Monday night into Tuesday.  Rain chances should be more or less
done by 00Z Wednesday.  Cooler conditions for the rest of the week
as the upper pattern amplifies with a deep trof over eastern North
America and a strong ridge over the Rockies. A shortwave is forecast
to ripple by Thursday which could produce another round of light
rain, tho differences in medium range guidance indicate slight
chance PoPs are the best way to handle it at this time.  Next Friday
looks cool and dry at this time as a strong Canadian high pressure
system slides down into the Mississippi Valley.



.AVIATION:  (For the 00z TAFs through 00z Saturday Evening)
Issued at 522 PM CDT Fri Oct 24 2014

A weak cool front will move southeastward through the area late
tonight. Fog is expected to develop late tonight ahead of this
front, and possibly also patchy stratus clouds as well, due to light
surface winds and relatively high surface dewpoints. This fog will
dissipate by late Saturday morning. A s-swly surface wind will
veer around to a nwly direction late tonight/early Saturday
morning after fropa.

Specifics for KSTL: Just high level clouds tonight and maybe
scattered low level clouds as well. Light fog can be expected late
tonight/early Saturday morning. Sly surface wind will veer around
to a nwly direction early Saturday morning after fropa. The
surface wind will become n-nely Saturday evening, albeit light as
a surface ridge moves through the region.



Saint Louis     59  78  55  79 /   0   0   0   5
Quincy          54  75  50  77 /   0   0   0  10
Columbia        56  79  55  83 /   0   0   0   5
Jefferson City  55  79  53  83 /   0   0   0   5
Salem           54  75  49  76 /   0   0   0   5
Farmington      55  77  51  80 /   0   0   0   0




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