000
FXUS63 KSGF 090204
AFDSGF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SPRINGFIELD MO
804 PM CST Sun Dec 8 2013

.UPDATE...
Issued at 750 PM CST SUN DEC 8 2013

Have updated the forecast this evening to increase coverage in
freezing drizzle which will result in a glaze of ice across the
forecast area this evening into the overnight hours.

The low levels of the atmosphere are currently saturated but the
middle and upper levels are dry resulting in no cloud ice. As a
weak front and an upper level disturbance push into the region,
this low level moisture is being squeezed out and freezing drizzle
is occurring across the entire area since there is no cloud ice.
Have gotten quite a few reports of roads icing up and slide offs
occurring due to this freezing drizzle.

There is an area of mid level moisture which will clip the
northern portions of the forecast area this evening, and will
provide some cloud ice and the potential for some scattered
flurries or light snow showers this evening. This snow activity
will be light but given the cold ground temperatures a dusting of
snow will be possible generally along and north of the Highway 54
corridor.

The drizzle will slowly end from west to east into the early
overnight hours. Expect areas west of Interstate 49 to see an end
of the freezing drizzle by midnight and will push east of the
eastern Ozarks by 3 AM.

With the cold temperatures and periods of freezing drizzle
occurring through the evening hours, have gone ahead and issued a
Winter Weather Advisory for the entire area, with areas west of
Interstate 49 until midnight and areas east of Interstate 49 until
3 AM. Even with the freezing drizzle coming to an end overnight,
slick spots on area roadways can be expected for the Monday
morning commute.

&&

.SHORT TERM...(This Evening through Tuesday night)
Issued at 240 PM CST SUN DEC 8 2013

As expected, a rather tricky day across the region. With the area
in and (mainly) out of cloud ice, areas of freezing drizzle
developed around sunrise and persisted for much of today.

Two big issues we are focusing on for this forecast is the
continue potential for freezing drizzle heading into this evening,
black ice potential tonight and another quick shot of light snow
Monday evening into Monday night.

For the rest of today through tonight, weak mid level lift is
departing and low level isentropic charts show neutral to very
weak upglide for a few more hours. As a result, current areas of
drizzle should become more patchy, coming to an end later this
evening. Another concern will be black ice potential. Loss of
solar insolation and temperatures falling back into the upper
teens will promote refreezing of all exposed surfaces. Continued
caution will be required on area roadways tonight into tomorrow`s
rush hour. With the freezing drizzle risk coming decreasing, will
go ahead and let the winter weather advisory expire and issue an
SPS for the expected conditions tonight.

Monday will remain cold and quiet, however yet another round of
wintry precipitation is expected to impact the area beginning
Monday evening. Short range models have been quite consistent the
past few days with bringing a fast moving wave through the region.
Frontogenetical forcing will yield a long/narrow band of snow
that looks to clip southern Missouri beginning early Monday
evening and exiting to the east overnight Monday night. The speed
of this system will limit accumulations to some extent, however
snow to liquid ratios around 15:1 and decent lift should yield a
quick inch or two of snow. Areas along and south of a line from
Pittsburg KS to Bolivar and Rolla in Missouri will experience this
light snow, with the better accumulations along and south of the
Highway 60 corridor. Further forecast refinements are expected,
and with this band expected to be so narrow any minor shifts in
the forecast will greatly affect snow accumulation expectations.

Tuesday and Tuesday night will be cold and quiet as another surge
of cold air enters the region.

.LONG TERM...(Wednesday through Sunday)
Issued at 240 PM CST SUN DEC 8 2013

Northwest flow will begin to flatten somewhat by the end of the
week. Medium range models indicate a cut off low over the
southwestern U.S. will move out into the southern Plains region by
Friday. Temperatures will remain cold with slow moderation through
the end of the week and next weekend.

The next question will be precip types as the upper level low moves
across the Missouri Ozarks. The latest guidance of models indicate
a little more QPF than previous runs with a progressive system
moving through. The GFS was the slightly warmer solution and the
ECMWF and GEM slightly colder.

With this package have leaned more with the ECMWF with a slightly
colder solution. Without being too detailed with precip
type this far out...this forecast update will mention rain and
snow chances for Friday through Saturday. This will be a system to
watch over the next few days. Temperatures will remain below
average especially where snow may still be on the ground.

&&

.AVIATION...(For the 00Z TAFS through 00Z Monday Evening)
Issued at 526 PM CST SUN DEC 8 2013

IFR and occasional LIFR conditions will persist overnight due to a
combination of low clouds, fog, and freezing drizzle. The freezing
drizzle will be patchy in nature...so we have chosen to cover this
with TEMPO groups. There is the potential for a brief period of
freezing fog later tonight behind a passing cold front. IFR is
expected to persist into Monday morning with ceilings finally
rising into the MVFR category by late morning. Weather models want
to bring in VFR in the afternoon, but we are not buying that
solution right now as we feel that remaining stratus clouds will
have a hard time clearing.

&&

.SGF WATCHES/WARNINGS/ADVISORIES...
MO...WINTER WEATHER ADVISORY until 3 AM CST Monday FOR MOZ055>058-
     067>071-078>083-089>092-094>098-102>106.

     WINTER WEATHER ADVISORY until Midnight CST tonight FOR MOZ066-
     077-088-093-101.

KS...WINTER WEATHER ADVISORY until Midnight CST tonight FOR KSZ073-
     097-101.

&&

$$

UPDATE...Wise
SHORT TERM...Gagan
LONG TERM...Griffin
AVIATION...Schaumann