000
FXUS63 KLSX 280939
AFDLSX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ST LOUIS MO
339 AM CST Wed Jan 28 2015

.SHORT TERM:  (Through Late This Afternoon)
Issued at 339 AM CST Wed Jan 28 2015

Satellite data at 08z showed the area of low clouds that had been
across west-central IL had moved off to the north, propelled by low
level flow from the SE, leaving behind clear skies across the entire
forecast area.  Temps were in the 20s for most areas save central MO
where readings were in the low 30s.  A surface warm front extended
from southern NE to northeastern OK.  NW flow prevailed aloft with
an upper level RIDGE over the Plains.

The surface warm front is expected to make steady progress today
into central MO by late afternoon.  While moisture levels in the
atmospheric column are expected to rise to above average levels, the
lack of any real deep lift other than from the front will preclude
any pcpn development thru early this evening.  In fact, clouds are
expected to be rather thin for much of the day until late, allowing
plenty of sunshine.

The high levels of sunshine and what should be a stout southerly
surface flow will allow temps to surge today, especially in central
MO where the surface warm front is expected to reach.  MOS temps
have been consistently on the cool side for similar scenarios this
year.  Forecasted values that were around the warmer MAV MOS for IL,
yielding 45-50F for maxes, and went up to a few degrees above the
MAV MOS for MO, yielding low 50s near the MS river to the low 60s in
central MO.

TES

.LONG TERM:  (Tonight through Tuesday)
Issued at 339 AM CST Wed Jan 28 2015

(Tonight through Friday)

With little precip expected thru the period, focus remains on temps.

Mdls are in very good agreement thru the period with respect to mass
fields and thermal profiles. Still, spread among MOS temps increases
thru the period, tho is less than usual. Have trended twd the warmer
guidance for tonight as clouds shud help keep temps warmer. Trended
twd a compromise thru the remainder of the period as cloud cover and
CAA will oppose one another, increasing uncertainty.

Continued low PoPs for nern/ern portions of the CWA for tonight and
Thurs morning as the clipper pushes thru the area.

(Saturday through Tuesday)

Focus quickly turns to the system approaching the region this
weekend. Mdls are in remarkably good agreement thru the end of the
storm on Mon. Overall, mdls are rather consistent compared to 24 hrs
ago. However, the ECMWF is slightly less amplified and slightly
warmer while the GFS suggests a deeper trof and overall cooler. The
GEM is further nwd with the 850 mb track compared to the other
solns.

Increased PoPs for late Sat thru Sun as mdls continue to suggest
precip thru this time and precip is expected. However, a fair amount
of uncertainty remains regarding p-type thru this storm. Still, it
shud remain largely a RA vs. SN system. With the uncertainty in the
thermal profile, only minor changes were made to p-types for this
system. This storm will remain one to monitor.

Beyond this storm, much colder air filters into the region as the
arctic sfc ridge builds into the area. Have trended slightly cooler.
Any SN pack from the preceding system may drive temps even cooler
than forecast. Will continue with an overall compromise for now.

Tilly

&&

.AVIATION:  (For the 06z TAFs through 06z Wednesday Night)
Issued at 1140 PM CST Tue Jan 27 2015

Stratus has straddled KUIN over the last few hours. Southeastern
edge however has pushed north and westward and may yield Quincy
with mostly clear skies in a couple of hours once again. With the
clear skies...fog will likely affect KUIN and KSUS/KCPS. Winds
will veer to the southeast and then south by morning. As pressure
gradient strengthens...winds will gust between 20 and 25 knots at
terminals. Mid to high level cloudiness should be on the increase
ahead of next weather system Wednesday afternoon/evening but
terminals are expected to remain dry.


Specifics for KSTL:

Some MVFR fog is possible at Lambert overnight tonight as
temperature approaches dewpoint. Winds aoa 5 knots however is
expected to preclude development so left out of TAF. Winds will veer
to the southeast and then south by morning. As pressure gradient
strengthens...winds will gust between 20 and 25 knots. Mid to high
level cloudiness should be on the increase ahead of next weather
system Wednesday afternoon/evening but terminals are expected to
remain dry. Trailing cold frontal boundary should move through
late Wednesday night/early Thursday morning. Winds will abruptly
swing to the west with gusts 25-30 knots.

Gosselin

&&

.PRELIMINARY POINT TEMPS/POPS:
Saint Louis     52  41  44  25 /   0  10  10   0
Quincy          49  36  40  21 /   0  20  10   0
Columbia        61  39  43  24 /   0  10   5   0
Jefferson City  62  39  45  24 /   0   5   5   0
Salem           45  39  43  25 /   0  20  20   0
Farmington      51  41  45  25 /   0  10   5   0

&&

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

$$

WFO LSX