Area Forecast Discussion
Issued by NWS St. Louis, MO

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FXUS63 KLSX 172304

604 PM CDT Fri Oct 17 2014

.SHORT TERM:  (Through Late Tonight)
Issued at 341 PM CDT Fri Oct 17 2014

Scattered to broken stratocumulus will begin to break up this evening
as some of this cloud cover is diurnally driven.  Partly cloudy
skies should stay through the night, particularly over the northern
and eastern counties where there will continue to be some low level
moisture in cyclonic flow.  Northwesterly winds will decrease early
this evening and went close to the agreeable MOS guidance for lows.


.LONG TERM:  (Saturday through Next Friday)
Issued at 341 PM CDT Fri Oct 17 2014

The subtle shortwave currently over Lake Winnipeg will dive south
and phase with the more prominent wave that`s gathering steam over
the northeast Plains and dive into the base of the longwave trof
over eastern North America on Saturday.  This will give the Canadian
airmass over Manitoba the final shove needed to send it streaming
into the Midwest.  Cool northerly flow will result on Saturday which
will keep temperatures mostly down in the upper 50s and low 60s.
Models are indicating another batch of stratocumulus will move
through with the shortwave on Saturday which should also help to
keep temperatures lower.

Strong high pressure will remain in place over the Ohio Valley
Sunday.  Sunday morning lows may be some of the coldest yet this
season as temperatures fall into the mid to low 40s across the
region.  Patchy frost in sheltered areas is a decent possibility.

The next shortwave in line dives through the Midwest Sunday night
into Monday.  The GFS is the wettest of the model suite, but the
ECMWF also develops some light precip ahead of the wave.  Have
increased PoPs to chance category before 12Z Sunday and kept slight
chance going during the day Sunday.  The cold front will go through
late in the day Monday, so it looks like there will be a decent warm
up during the day in southwest flow with highs reaching the upper
60s or low 70s.

Medium range guidance continues to develop a very blocky pattern
with Monday`s shortwave cutting off into a giant low over the East
Coast.  Upper level ridging over the Midwest should keep us dry with
an elongated surface ridge stretching from southeast Canada back
through the Mississippi Valley into the southeast Plains through the
end of the week.  Temperatures should say near or just a few degrees
below normal through the period.



.AVIATION:  (For the 00z TAFs through 00z Saturday Evening)
Issued at 548 PM CDT Fri Oct 17 2014

Strong and gusty winds will diminish with sunset as the sfc ridge
builds into the region. BKN clouds will remain along the MISS
River early this eve before dissipating and moving ewd. Can not
rule out clouds becoming bkn Sat mid to late morning. However, if
cigs develop, bases shud be around 3 kft briefly before lifting
into VFR range. Winds tomorrow shud be aob 10 kts.





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