000
FXUS63 KDDC 052318
AFDDDC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DODGE CITY KS
518 PM CST Thu Dec 5 2013

...Updated aviation section...

.SYNOPSIS...
ISSUED AT 1115 AM CST THU DEC 5 2013

At 12z Thursday a 1400-160kt 300mb jet extended from northeast
Colorado into the western Great Lakes. Another upper level jet was
located near the based of the 500mb trough that was positioned from
southern California into southwest Montana. A -25 to -32c 500mb
thermal trough was located near the four corners region. A surface
to 850mb ridge axis was located across from western Nebraska into
western Oklahoma and a surface cold front extended from eastern
Colorado south southeast across eastern New Mexico into west
central Texas.

&&

.SHORT TERM...(This evening through Friday)
ISSUED AT 217 PM CST THU DEC 5 2013

Upper level through that was located across southern California
and Nevada earlier today will track east and cross New Mexico by
late day. Ahead of this this upper trough some mid level moisture
will linger across western Kansas. Backing 700mb winds ahead of
this upper wave appears to enhance frontogenesis across portions
of southwest Kansas late today and early this evening which may
give rise to a period of steady light to moderate snow. Both the
NAM, GFS, and even the RAP hints at enhanced precipitation briefly
ahead of this wave along this baroclinic zone so will follow this
trend through midnight as the upper level trough moves out into
the central high plains. Given the potential for a period of
steadier snow early tonight could easily see snowfall
accumulations in the one to two inch range given the high liquid
to snow ratio. The area more favorable for this measurable
snowfall still appears to be along and south of a Ulysses to Dodge
City to Pratt line. Snow totals of around two inches still not out
of the question near the Oklahoma border so will trim several
counties out of the current winter weather advisory.

Tonight the dewpoint will be at or several degrees below zero
under mostly cloudy skies. Temperatures will be slow to fall this
evening but at this time given these expected low dewpoints, last
nights temperatures across northwest Kansas, and the low levels
cooling by a couple more degrees have decided to stay close to the
guidance for overnight lows. Given these overnight lows ranging
from around 1 degree in west central Kansas to near 10 degrees in
south central Kansas along with wind speeds of around 10 mph the
wind chills by early Friday morning are expected to fall back into
the -8 to -15 degree range. The coldest wind chills early Friday
morning will be across west central Kansas so will be issuing a
wind chill advisory for this area late tonight/early Friday.

On Friday the upper level trough will move east into the mid
Mississippi valley. Subsidence behind this disturbance may give
rise to some breaks of sun late in the day as high pressure at the
surface will continue to build into western Kansas. Despite to
break of sunshine the 900-850mb temperatures continue to support
highs only in the teens Friday afternoon.

.LONG TERM...(Friday night through Thursday)
ISSUED AT 209 PM CST THU DEC 5 2013

Friday night:

Sfc high pressure will shift off to the east Friday night. This will
result in northeasterly winds eventually shifting southeast on the backside
of said departing high. A cold night is expected with minimums near
0F. Would not rule out a few negative values if skies clear more than
expected. Will have to watch for the potential for a wind chill advisory
during the overnight and morning hours.

Saturday and beyond:

The forecast becomes a bit more interesting during the weekend. An amplified
trof will eject from the central Rockies and out across the plains by
Sunday. This wave does have some upper level dynamics associated with
it (140-150 kt jet streak traverses across the forecast area of responsibility).
At the low levels, fairly intense warm air advection, 280-290 Kelvin
isentropic lift, and 850-600 mb increasing frontogenesis will lead
to snow late Saturday and into Sunday. The more enhanced area of said
parameters is forecast along and north of the 850 mb pressure perturbation
...basically the northern half of the forecast area. Models still show
low end snow advisory amounts along and north of highway 96. Even some
of the GEFS members show 2-4" of snow. There is huge bust potential
in temperatures for Sunday, should this snow/snow pack/cloud cover come
into fruition. The ECE shows a high of 8 for KDDC versus 22 from the
MEX. Will apply a slight bias towards the ECMWF solution versus the
GFS. Boise verification shows this guidance doing better than the
MEX with the current cold air mass over Kansas.

After Sunday, the forecast will remain precipitation free as isentropic
downglide and subsidence develops in the wake of the departing synoptic
trof. There is some question of when this cold air will be dislodged
and more of a low level 850 mb downslope plume will develop. The ECMWF
indicates this possibility of seeing "warmer" temperatures (i.e. above
freezing) by mid to late next week. The deterministic runs have been
fairly consistent over the last few days.

&&

.AVIATION...(For the 00Z TAFS through 00Z Friday evening)
ISSUED AT 515 PM CST THU DEC 5 2013

Light snow showers will be possible across the DDC and GCK TAF
sites over the next couple of hours. This will bring MVFR
conditions to these terminals. The HYS terminal should remain dry
with cloudy skies. Winds will generally be from the north at 5 to
10 knots throughout the night into tomorrow morning.

&&

.PRELIMINARY POINT TEMPS/POPS...
DDC   5  15   0  16 /  70   0   0  30
GCK   2  15   0  13 /  50   0   0  30
EHA   2  13   1  17 /  80   0   0  30
LBL   5  15   0  15 /  80   0   0  30
HYS   4  15   0  15 /  20   0   0  40
P28  10  21   4  20 /  50  10   0  40

&&

.DDC WATCHES/WARNINGS/ADVISORIES...
WIND CHILL ADVISORY from Midnight CST /11 PM MST/ tonight to 9
AM CST /8 AM MST/ Friday FOR KSZ043-044-061>063.

WINTER WEATHER ADVISORY until 9 PM CST this evening FOR
KSZ084>088.

&&

$$

SYNOPSIS...Burgert
SHORT TERM...Burgert
LONG TERM...Sugden
AVIATION...Hovorka_42