Area Forecast Discussion
Issued by NWS St. Louis, MO

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FXUS63 KLSX 280856

Area Forecast Discussion
National Weather Service Saint Louis MO
356 AM CDT Fri Oct 28 2016

.SHORT TERM...  (Through Late Tonight)
Issued at 353 AM CDT Fri Oct 28 2016

High pressure over the Ohio Valley will move eastward into the Mid
Atlantic States.  This is producing increasing south-southeast flow
this morning...which along with some widespread cirrus seems to be
putting the kibosh on much of our fog chances.  Am keeping some
mention of fog in the forecast for this morning, but current
indications are that widespread dense fog (visibility 1/4 mile or
less) is becoming less and less likely.  Wind will continue turning
to the south-southwest today.  Strong warm advection will bring
temperatures up at least 10 to 15 degrees above Thursday`s highs.
Record high temperatures at St. Louis, Columbia, and Quincy appear
to be safe at 85 degrees today...but readings in the upper 70s and
low 80s look attainable at all three sites.  Warm southwest flow will
continue tonight which will keep temperatures well above normal...
mainly in upper 50s to lower 60s.  Normal lows for late October
are in the low to mid 40s.


.LONG TERM...  (Saturday through Thursday)
Issued at 353 AM CDT Fri Oct 28 2016

Unseasonably warm conditions will continue on Saturday with
southwesterly surface/low level winds and 850 mb temperatures of 14-
18 degrees C.  Plenty of solar insolation is expected with only some
high level clouds.  High temperatures will be about 20 degrees above
normal for late October.  A weakening cold front will drop southward
through our forecast area late Saturday night and Sunday as a
shortwave moves eastward through the Great Lakes region.  It appears
that any precipitation will remain north and east of our forecast
area, although could not rule out isolated light showers mainly late
Saturday night across northeast MO and west central IL.  This front
should make it into southern portions of MO and IL Sunday afternoon.
Highs will be cooler on Sunday, especially across northeast MO and
west central IL behind the front due to weak cold air advection and
low level cloud cover, albeit still above normal.  This weak front
will lift back northward as a warm front on Monday. Highs on Monday
will be unseasonably warm and similar to Saturday as south-
southwesterly winds return.  The GFS model brings precipitation
southeastward into our area already by late Tuesday night and
Wednesday ahead of an approaching upper level trough over the
northern Plains and an associated cold front.  Prefer the ECMWF
model solution which does not bring showers into our area until
Wednesday night as the positively tilted upper level trough sharpens
and the cold front drops southeastward into our forecast area.  The
cold front and its associated precipitation along it should shift
southeast of our forecast area by Thursday evening.  Cooler
temperatures can be expected on Thursday after the long stretch of
unseasonably warm weather.



.AVIATION...  (For the 06z TAFs through 06z Friday Night)
Issued at 1136 PM CDT Thu Oct 27 2016

Still looking at fog potential overnight into early Friday
morning. Present indications are the best potential for fog will
be along and east of the MS River. KCPS, and to a lesser degree
KSUS, would appear to have the best potential and I have flight
conditions reduced to IFR within the 10-14z time frame. Lesser
restrictions at KUIN and KSTL with MVFR flight condtions. Still
more uncertainty in central MO for fog and have left out any
mention. Any fog should dissipate by 15z or so with VFR
dominating thereafter and increasing southerly winds.


Still uncertainty in the potential for fog overnight. Winds
tonight will be light southeasterly and there should be decent
radiational cooling and potential for at least fog in the 10-14z
time frame reducing the visibility down to 5sm. Confidence is low
on any lower flight conditions at this time, but certainly not out
of the question. Any fog should dissipate by 15z or so with VFR
dominating thereafter and increasing southerly winds.



Issued at 250 PM CDT Thu Oct 27 2016

With an upcoming stretch of unseasonable warmth expected over the
weekend into early next week, here is a list of record high
temperatures. Although there are no record high temperatures in
the forecast just yet, some record values may be in jeopardy
Saturday and perhaps on Monday.

     STL    COU     UIN
Fri10/28 85/1927 85/1927 85/1927





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