Area Forecast Discussion
Issued by NWS St. Louis, MO

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000
FXUS63 KLSX 291751
AFDLSX

AREA FORECAST DISCUSSION...UPDATED AVIATION
NATIONAL WEATHER SERVICE ST LOUIS MO
1251 PM CDT Mon Jun 29 2015

.SHORT TERM:  (Through Late This Afternoon)
Issued at 148 AM CDT Mon Jun 29 2015

Weak surface low just northeast of STL will continue moving
eastward.  The thunderstorms have shifted east or south of our
forecast area, with only a few lingering showers between STL and
SLO.  Some fog has developed across west central IL and northeast MO
between UIN and HAE where the temperature has fallen into the 60s
and the wind has become light.  Will likely get at least isolated to
widely scattered showers and a few storms across our area this
afternoon as the atmosphere destabilizes with weak northwest flow
shortwaves moving southeastward through our area.  It appears that
the best coverage will be across northeast MO and west central and
southwest IL where there will be cooler mid level temperatures
associated with the upper level trough and hence better lapse
rates.  High temperatures today should also be a little cooler
across this area as well.

GKS

.LONG TERM:  (Tonight through Sunday)
Issued at 345 AM CDT Mon Jun 29 2015

At least isolated to widely scattered showers and a few storms
during the afternoon and evening will continue Tuesday.  High
temperatures will be slightly warmer on Tuesday as the upper level
trough shifts further eastward and warmer 850 mb temperatures advect
east northeastward into our area.  Rain chances will be increasing
late Tuesday night and Wednesday as a southwesterly low level jet
brings strong low-mid level warm air advection and 850 mb moisture
convergence to central MO by 12Z Wednesday.  More cloud cover and
more widespread precipitation will lead to cooler high temperatures
on Wednesday.  A good chance of convection will continue through at
least Wednesday night as a relatively weak surface low moves
eastward through southern MO.  Much of the precipitation may shift
southeast of our forecast area on Thursday as this surface low
shifts east southeast of the region with at least weak surface
ridging extending from the northern Plains and Great Lakes region
south southwest into our area.  This may only be a brief break in
the wet pattern as both the GFS and ECMWF models bring an upper
level trough east southeastward through our area late Thursday night
through Friday night.  This upper level trough with embedded
shortwaves should lead to at least scattered showers/storms during
the afternoon and evening hours.

GKS
&&

.AVIATION:  (For the 18z TAFs through 18z Tuesday Afternoon)
Issued at 1247 PM CDT Mon Jun 29 2015

Surface low over central Indiana will continue to weaken and lift
to the northeast. However will stay in busy northwest flow aloft
with more shortwaves sliding south into region. Cu has begun to
lift a bit and scatter out more so cigs for the most part are VFR
for rest of forecast period. Could see some isolated showers
develop this afternoon, but coverage is minimal so did not add
mention to tafs at this time. Otherwise, north winds to back to
the northwest to west and become light. Then winds to pick back up
a bit by mid morning on Tuesday from the west.

Specifics for KSTL:
Surface low over central Indiana will continue to weaken and lift
to the northeast. However will stay in busy northwest flow aloft
with more shortwaves sliding south into region. Cu has begun to
lift a bit and scatter out more so cigs for the most part are VFR
for rest of forecast period. Could see some isolated showers
develop this afternoon, but coverage is minimal so did not add
mention to taf at this time. Otherwise, north winds to back to
the northwest to west and become light by 02z Tuesday. Then winds
to pick back up a bit by 15z Tuesday from the west.

Byrd
&&

.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&

$$
WFO LSX





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