Area Forecast Discussion
Issued by NWS St. Louis, MO

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FXUS63 KLSX 060853

353 AM CDT TUE OCT 6 2015

.SHORT TERM:  (Through Late This Afternoon)
Issued at 350 AM CDT Tue Oct 6 2015

Scattered sprinkles/light rain showers have developed over
northwestern MO early this morning ahead of a weak vort max in
northeastern KS. The area with light sprinkles also coincided with
an area of moisture convergence between H8-H7 as well as a pocket of
steeper lapse rates. A few sprinkles or light rain showers could
move into central or northeastern MO this morning.

The slow warming trend continues today with afternoon highs expected
to be a few degrees warmer than yesterday. This should lead to highs
in the 70s across most of the area, although a few sites in
southeastern MO and/or southwestern IL could reach the lower 80s
depending on how quickly the clouds clear out.


.LONG TERM:  (Tonight through Monday)
Issued at 350 AM CDT Tue Oct 6 2015

Forecast trends will remain essentially unchanged in this
forecast package: dry and mild weather is expected tonight and
into Wednesday, followed by a chance of showers and thunderstorms
in the Thursday-Friday time frame as upper level shortwave and
trof and associated cold front work their way across the
Mississippi Valley. The only real change in the forecast was a
slight slowing of the southward progression of PoPs across the
area, as all of the 00z guidance was just a bit slower with the
shortwave and cold front than earlier solutions. The slower
solutions also dovetails with the idea of holding onto low chance
PoPs over southern sections of the CWA on Friday. Have decided to
maintain highest PoPs for this event at around 50% for
now...although MET and MAV are considerably lower operational
ECMWF-based MOS guidance is indicating likely PoPs in many areas
with the fropa. Additional adjustments to PoPs will probably be
necessary with time as the details become a bit more clear.

Daytime highs will be above average on Wednesday and Thursday with
highs in the middle 70s to lower 80s.  However, temperatures will be
dipping below seasonal norms by Friday, as the post-frontal cool-
down shaves some 10-15 degrees off of max temps.

Medium range solutions are still indicating that this cool down will
be brief, as the progressive UA regime across the CONUS allows a
strong ridge to build back into the nations`s midsection for the
start of next week.  Guidance is suggesting 850MB temps of at least
16-18C on Monday, which would certainly support highs back in the
80s over most of the CWA. Lack of moisture and any significant
dynamics/lift suggest dry weather will accompany this warmup.



.AVIATION:  (For the 00z TAFs through 00z Tuesday Evening)
Issued at 652 PM CDT Mon Oct 5 2015

Weak upper level system will move across the region te next 24
hours bringing back the northwest flow aloft. Main question is
will the mvfr clouds return: all sites vfr at taf issuance. Have
gone VFR for now with the idea that extensive mid and high clouds
will prevent widespreas redevelopment. Some sprinkles possible
from the mid clouds from the upper level system. Will watch cloud
trends closely for COU and UIN.

Specifics for KSTL: RAP noses in some lower RH values from the
east. This along with the mid and high clouds should keep STL VFR.
Fingers are crossed.



Saint Louis     77  61  79  63 /   5  10   5   5
Quincy          74  56  77  59 /  10  10  10  10
Columbia        74  57  78  60 /  20  10  10  10
Jefferson City  74  57  78  59 /  20  10  10  10
Salem           77  57  79  59 /   5  10   5   5
Farmington      76  56  77  57 /   5  10  10   5




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