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Area forecast discussion 
National Weather Service Springfield MO
241 am CST Wed Nov 26 2014

Short term...(today and tonight)
issued at 142 am CST Wednesday Nov 26 2014

A small, fast moving, but vigorous shortwave is digging southeast
into eastern neb/western Iowa. Strongly diffluent flow aloft with
the exit region of jet streak has spread southeast into NE Kansas and
NW MO and radar reflectivity returns have reached as far southeast
as the kc Metro. However, with dry air in place at lower levels,
some of this precip along the leading edge is not reaching the
ground. Farther to the NW, obs do eventually see a mix of rain and
snow.

We should see the shortwave continue to dig to the southeast into
the forecast area by midday/18z with the strongest lift moving
quickly across the region this morning, especially over the
northeast half to three quarters of the cwfa. Low level warm
advection and clouds have allowed temperatures to remain
relatively mild over the western cwfa tonight and expect that
trend to continue from west to east over the next few hours.
Basically lift/evaporative cooling from precip aloft will fight
warm advection/limited diurnal heating in terms of low level
temperature profiles this morning. In general went with a high res
model blend in terms of timing/temperatures/thermal profiles. In
short, we should see a mix of rain and snow (maybe a little sleet
at onset), similar to what we are seeing upstream. Have edged the
accumulating snow a little farther southwest versus previous
forecasts with the highest amounts over the northeast cwfa/Lake of
The Ozarks region (0.5-0.7 inches) where the snow could very
briefly be more intense. The short residence time of the strong
lift in any one area along with relatively warm sfc temperatures
and limited solar thermal radiation will limit snow amounts. Some
slick spots on roadways will be possible for a brief time where
more intense snow can fall early this morning. Given the small
scale of the system, there will still be some maneuvering of the
forecast and forecast message/impacts based on observed trends.

Blustery winds veering to the west and northwest can also be
expected today with some gusts of 30-35 mph possible over the
western cwfa toward midday behind the trailing sfc front.

Long term...(thursday through tuesday)
issued at 142 am CST Wednesday Nov 26 2014

No big changes to the forecast for Thanksgiving and into the
weekend. A sfc ridge of Canadian high pressure nosing south into
the central U.S. Will shift west-east through MO on Thursday. A
quick warm up will develop Friday as a flat upper ridge moves east
into the the central Continental U.S.. warm temperatures will continue over
the upcoming weekend.

A split upper level flow develops late in the week, and a
shortwave in the northern stream will allow a cold front to move
into the area late Sunday and Sunday night. Not looking at
brutally cold air which will remain to the north, but highs will
be colder by Monday (30s and 40s). Not entirely sold on a warming
trend for Tuesday, but will go with a model blend. Quite a bit of
divergence in guidance patterns start to emerge early next week,
so hard to argue with the fcst blend/mean at this point.

&&

Aviation...(for the 06z tafs through 06z Wednesday night)
issued at 1143 PM CST Tuesday Nov 25 2014

A quick moving storm system will dive southeast across the region
late tonight and Wednesday morning. Weather models have trended a
bit further west and south with precipitation. We therefore
believe that a brief period of IFR will occur Wednesday morning at
the Springfield Aerodrome as a band of snow pushes through. A
mixture of rain and snow is expected at Joplin and Branson. This
mix will keep visibilities more in the MVFR range. We will also
see a brief period of low level wind shear conditions Wednesday
morning. As precipitation ends later Wednesday morning, brisk and
gusty northwest surface winds will develop. We may also see a
period of MVFR ceilings behind this departing system Wednesday
afternoon at the Springfield terminal.



&&

Sgf watches/warnings/advisories...
MO...none.
Kansas...none.
&&

$$

Short term...dsa
long term...dsa
aviation...schaumann

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