Area Forecast Discussion
Issued by NWS St. Louis, MO

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FXUS63 KLSX 271807

Area Forecast Discussion...Updated Aviation
National Weather Service Saint Louis MO
107 PM CDT FRI MAY 27 2016

.SHORT TERM...  (Through Late This Afternoon)
Issued at 405 AM CDT Fri May 27 2016

Early this morning...southwest flow aloft existed with a stream of
upper level disturbances tracking into our region from the Lower MS
Valley and TX Gulf Coast.  A strong storm system anchoring all of
this was centered over eastern CO.  Radar mosaic showed this stream
of disturbances from southeast MO thru the eastern half of TX with
the leftovers of the main severe wx event yesterday from the main
storm system in eastern CO now working its way thru far western MO
but is weakening.

This pattern should continue thru much of today, with the first
solid area of rain working its way thru early this morning for
southeast MO, STL metro and southern IL.  The weakening remnants of
the Plains convection should continue into central MO later this
morning.  After perhaps a brief interlude in the pcpn, another round
of showers and t-storms should build back into the area late this
afternoon and continue thru this evening with the next embedded
disturbance rolling northeastward.

Due to the clouds and high PoPs today, went conservative with max
temps, and kept most locations in the 75-80 range.  Min temps
tonight should be in the 65-70 range with dewpoints already in the
mid 60s.


.LONG TERM...  (Tonight through Thursday)
Issued at 405 AM CDT Fri May 27 2016

Southwest flow aloft continues for one more day and will maintain
the areawide rain threat, ending with passage of a surface cold
front later on Saturday night.

After a brief dry period on Sunday and much of Monday with a weak
RIDGE aloft and surface high pressure prevailing, a resumption of
this wet pattern will occur late Monday and for much of the
remainder of next week with southwest flow aloft again and a stream
of upper level disturbances.

Temperatures will remain at or above average during this period with
max temps mainly in the 80s and mins in the 60s.



.AVIATION...  (For the 18z TAFs through 18z Saturday Afternoon)
Issued at 1238 PM CDT Fri May 27 2016

Difficult forecast regarding precipitation trends for this valid
TAF period. Believe chances for showers and thunderstorms will
increase this afternoon into very early evening ahead of next
shortwave. Could be a lull tonight with another wave late
tonight/early on Saturday possible. Other concern in the near term
is the MVFR ceilings but expect only a short period of these
ceilings before they lift into VFR.

Specifics for KSTL:

MVFR ceilings likely next few hours. Scattered showers and storms
also expected to increase this afternoon ahead of next shortwave
trough. Convective trends become more ambiguous overnight tonight
and into the day on Saturday.





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