Area Forecast Discussion
Issued by NWS St. Louis, MO

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
000
FXUS63 KLSX 272049
AFDLSX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ST LOUIS MO
249 PM CST Thu Nov 27 2014

.SHORT TERM:  (Through Late Tonight)
Issued at 245 PM CST Thu Nov 27 2014

Surface ridge to begin moving off to the east tonight allowing winds
to become southerly by daybreak. Lingering mid and high clouds to
keep temperatures from dropping like a brick but will still see lows
in the upper teens to mid 20s.

Byrd

.LONG TERM:  (Friday through Next Thursday)
Issued at 245 PM CST Thu Nov 27 2014

On Friday, we begin to warm up as winds pickup from the south,
gusting to near 25 mph at times, under mostly sunny skies. Highs
will be in the mid 40s to mid 50s. Milder Friday night with lows
in the mid 30s to mid 40s.

Saturday forecast a bit tricky. Models try to develop some light qpf
in warm sector ahead of next frontal boundary. Feel that it is
overdone and that it will be dry. Thus with models trying to develop
precipitation it is also indicating more clouds. Backed off on cloud
cover a bit to be partly cloudy across my area. Warm southerly winds
to persist so will see highs in the mid 50s to mid 60s.

Saturday night models begin to bring frontal boundary into forecast
area. Sided with the slightly slower NAM/ECMWF solutions. So expect
another mild night in the low 40s to low 50s. On Sunday front to
move through forecast area. So will see a wide range in high
temperatures ranging from the mid 50s far north to the upper 60s far
south. Low level moisture on the increase ahead of front so could
see some light precipitation develop over southeast half of
forecast area. Then as front pushes south of forecast area late
Sunday into Sunday night precipitation to shift a bit further
south...but could see some activity as far north as I70 corridor.
With colder air filtering in will see rain mix with and snow at
times. On Monday, as surface ridge settles into region, some
lingering mixed precipitation across far southern portions of
forecast area as highs will only be in the upper 20s to upper 30s.

Beyond that, extended models have very different solutions for
weather across the area around mid week. So confidence is low an any
of them. GFS keeps zonal flow and wants to bring in precipitation
for Wednesday night and Thursday while ECMWF wants to bring in an
upper level trof centered over great lakes and strong surface ridge
which would mean dry and cold conditions. For now have slight
chance/low end chance pops for this period with highs in the 40s and
lows in the upper 20s to mid 30s.

Byrd
&&

.AVIATION:  (For the 18z TAFs through 18z Friday Afternoon)
Issued at 1123 AM CST Thu Nov 27 2014

MVFR ceilings should move east of all TAF sites by around 22Z. VFR
cloud deck near 7000 feet then approaches from the west this
evening. Northwest winds will diminish rapidly this afternoon and
become light and variable overnight as surface ridge moves
overhead. Quick return to southeasterly flow on Friday with VFR
conditions expected.

Specifics for KSTL: MVFR ceilings should clear KSTL TAF site by
around 22Z. An area of VFR ceilings will move in after 00Z. Northwest
winds will diminish this evening. As surface high pressure moves
quickly off to the east, southeast winds will return by around
14Z.

Browning
&&

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

$$
WFO LSX




USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.