Area Forecast Discussion
Issued by NWS Springfield, MO
FXUS63 KSGF 090913
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SPRINGFIELD MO
313 AM CST Mon Dec 9 2013
...WINTER WEATHER ADVISORY POSTED THIS AFTERNOON AND TONIGHT...
.SHORT TERM...(Today through Thursday night)
It`s been quite the weekend regarding wintry weather. Following a
6 to 10 inch snowfall across southern Missouri, freezing drizzle
spread over the entire region, causing a glaze of ice to
accumulate on exposed surfaces, including roadways. Probably one
of the better freezing drizzle events we`ve had in several years
as far as causing impact to motorists.
More wintry weather will occur as early as this afternoon and
tonight. A nice disturbance was tracking over the central Rockies
this morning, and will approach the Ozarks this afternoon.
Global models all agree on a belt of lift to overspread areas
roughly along and south of a Columbus Kansas to Rolla Missouri
line. This will force minor snow accumulations over this region
this afternoon and tonight. Accumulations should remain at two
inches or less, since only Pacific based moisture will be
available to this disturbance.
With decent agreement shown by the global models, we took an even
blend between the Canadian, GFS, and the ECMWF to calculate
accumulation amounts. Roughly a 12:1 ratio was used given the low
level temps expected.
This belt of snow will completely exit the Ozarks Region early
Tuesday morning, setting the stage for cold and dry weather from
Tuesday through Thursday night.
Split flow evolves once again during the Tuesday through Thursday
night period. The Ozarks Region will be influenced more by the
northern stream, which offers cold northwest flow through most of
the week. Look for temperatures to warm into the lower 30s on an
afternoon basis, with overnight lows falling into the teens.
.LONG TERM...(Friday through Sunday)
Due to the ECMWF`s superior performance with it`s winter time mass
fields, the Friday through Sunday forecast is highly leaned in
The Euro suggests that a cutoff Baja upper low will eject toward
the region late in the week. This feature will tap into a Gulf
moisture feed and force a wintry mix of precipitation across the
Ozarks starting Friday.
Taking a glance at low level thermal fields, an ECMWF perfect prog
would provide a mix of snow, sleet, and liquid rain across the
Ozarks. Therefore we have a mention of all three precipitation
types in for the Friday and Friday night time frame. Hopefully we
will become a little better detailed with these types as the week
progresses, but for now we won`t get too cute with it.
For Saturday and Sunday, we remain in cyclonic flow in the upper
levels, which could promote small scale disturbances to set off
either freezing drizzle or light snow through the rest of the
One thing is for sure, it`s going to get cold again Saturday and
Sunday, as another shot of Canadian air spread through southern
.AVIATION...(For the 06Z TAFS through 06Z Monday Night)
Issued at 1120 PM CST SUN DEC 8 2013
Light fog and freezing drizzle will persist during the early
overnight hours around Springfield and Branson. The freezing
drizzle threat has come to an end at Joplin. Ceilings will
generally remain in the MVFR category, but an occasional drop to
IFR is still expected at Springfield and Branson. Enough low level
dry air may then work into Joplin Monday morning to bring a brief
window of VFR conditions. However, current thinking is that MVFR
will persist at Springfield and Branson. Another weak upper level
disturbance will then push into the region from late Monday
afternoon into Monday evening. This will result in more lowering
ceilings and developing snow. Confidence for snow is highest at
Joplin and Springfield where IFR conditions are expected. Snow is a
little more in question at Branson...thus we have gone with a
MO...WINTER WEATHER ADVISORY until 3 AM CST early this morning FOR