Area Forecast Discussion
Issued by NWS St. Louis, MO

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FXUS63 KLSX 220902

402 AM CDT Mon Sep 22 2014

.SHORT TERM:  (Through Late This Afternoon)
Issued at 354 AM CDT Mon Sep 22 2014

The work week will start quiet and dry. An area of high pressure is
expected to move across the nthrn portion of the CWA today allowing
winds to become more E/SErly by this aftn. This will keep winds fairly
light and mixing heights around 900mb. Combine that mixing height
with 850mb temps rising to 10-12 degrees by 00z leads to max temps
in the mid/upper 60s. Add a few degrees on for a superadiabatic lapse
rate near the surface and highs should be near 70...and MOS guidance
supports those figures. Monday and Monday night will be the coolest
24 hr prd this week with a slow moderation in temps beginning on


.LONG TERM:  (Tonight through Sunday)
Issued at 354 AM CDT Mon Sep 22 2014

Tranquil, dry weather pattern with a very gradual warming trend
beginning Tuesday.  Good radiational cooling tonight will lead to
slightly below normal low temperatures in the 40s. Upper low now
over southern Idaho will move out into the northern Plains with
some convection ahead of it spreading into northwest MO as early
as Tuesday or Tuesday night. It appears that the precipitation
will remain northwest of our forecast area due to dry and stable
atmosphere in the low-mid levels associated with the persistent
surface ridge extending from the Ohio Valley and northeast US west
southwest into eastern and southern MO. The upper level low will
weaken and likely begin to retrograde west southwestward through
the central Plains Thursday night and Friday. As the surface ridge
eventually weakens and a weak upper low comes up from the
southern Plains there may be a slight chance of showers/storms by
Sunday or Sunday night.



.AVIATION:  (For the 06z TAFs through 06z Monday Night)
Issued at 1140 PM CDT Sun Sep 21 2014

A ridge of high pressure is building into the region, which will
ensure VFR conditions at all TAF sites except for KSUS, which
might be affected by steam fog between 09-12z. Northerly winds
will gradually veer through the period with wind speeds remaining
AOB 10 kts.

Specifics for KSTL: VFR with northerly winds veering to become
easterly towards the end of the 30-hr TAF period.





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