000
FXUS63 KDDC 102318
AFDDDC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DODGE CITY KS
518 PM CST Tue Dec 10 2013

...Updated aviation discussion...

.SYNOPSIS...
ISSUED AT 1010 AM CST TUE DEC 10 2013

Water vapor imagery and 12Z upper air analysis indicate an upper
level shortwave moving quickly east across the Ohio River Valley.
Meanwhile, a secondary upper level shortwave is dropping southeast
across southern Canada. Near the surface, a weak lee side trough
of low pressure is slowly strengthening across extreme eastern
Colorado. A small amount of moisture has returned to the area
with surface dewpoints back above 0F across west central Kansas
to near 10F in south central Kansas.

&&

.SHORT TERM...(This evening through Wednesday)
ISSUED AT 200 PM CST TUE DEC 10 2013

Short range models indicate the upper level shortwave in southern
Canada shifting southeast across the Northern Plains tonight. Even
though an attendant cold front will push southward through western
Kansas overnight, dry conditions are expected to persist through
Wednesday afternoon with a lack available low level moisture.
Cold, but closer to seasonal temperatures, are expected tonight as
the aforementioned cold front moves through the region. Colder air
will filter southward into western Kansas sending H85 temperatures
back down below 0C across the entire region with near 5C below in
central and west central Kansas. This will likely drop lows well
into the teens(F) with a few upper digits(F) possible in west
central Kansas and near the I-70 corridor in central Kansas. A
surface high in the Dakotas will then sink south-southeast into
central and eastern Kansas Wednesday helping to lock in this next
push of arctic air in across the Western High Plains with H85
temperatures remaining well below 0C. Expect highs only up into
the 20s(F) across central Kansas with the lower to mid 30s(F)
possible across extreme southwest Kansas.

.LONG TERM...(Wednesday night through Tuesday)
ISSUED AT 406 PM CST TUE DEC 10 2013

Thursday through Saturday:
a southern stream upper low will be moving across the Desert
Southwest region Thursday and move across the Southern Plains by
late Friday.  In advance of this upper low, seasonal average
temperatures are forecast with lower to mid 40s common across the
region as a large surface high moves away from the region and a lee
trough develops across eastern Colorado by late in the day. Mixing
should be shallow as surface trajectories will still be from the
remnant Canadian airmass in the wake of the departing high...despite
decent downslope warming in the 850-700mb layer. Marginal low level
moisture off the surface will will move toward southern Kansas early
Friday...however these trajectories favor best moist advection
across south-central and southeastern Kansas early Friday.  The
veered low level trajectories and the fast-moving nature of the
upper air disturbance will not favor precipitation across much of
the southwest Kansas region. We will still keep some 15 to 20 POPs
across Barber County mainly during the Friday morning hours.  If
there is any precipitation as far west as Barber County...the
precipitation type could be in the form of light freezing rain
should the temperature at that time be below freezing...as
temperatures in the warm layer aloft are expected to be well above
0C. Some downslope-modified cold air advection will be found in
the wake of this disturbance Friday and Saturday with the bulk of
the coldest air expected well to the northeast of the southwest
Kansas region. Highs Saturday should recover back into the 40s
over much of the area except central Kansas counties where 30s are
forecast for highs.

Sunday and beyond:
The global models are showing another slug of arctic air moving
south down the Northern Plains on Sunday...thanks to another
northwest flow upper level disturbance moving southeast through the
Upper Midwest region. While the best forecast for Sunday at this
point is highs in the mid-upper 40s for most of the region, the
southwest edge of the arctic airmass will need to be watched very
closely...and could potentially have profound effects on
temperatures...especially up around Hays.  There is a high bust
potential for Sunday high forecast. The ECMWF shows brutally cold
air Sunday within the core of the arctic airmass Sunday up across
the Midwest region with highs in the teens as far south as
east-central Nebraska.   If we well into the warm sector
Sunday...portions of far southwest/west-central Kansas could see
highs into the lower 50s. This arctic airmass...should it reach as
far southwest as portions of our southwest Kansas region...will most
likely erode away early next week as northwest flow downslope
momentum favors modification of any cold airmass across the western
plains. We will most likely remain in this northwest flow pattern
through Tuesday or even Wednesday of next week with potential for a
formidable warm-up. The next major shift in the sensible weather
picture probably will not occur until the December 20-23 time frame
when there are some signals in the global spectral model solutions
of a deep trough forming across western North America.

&&

.AVIATION...(For the 00Z TAFS through 00Z Wednesday evening)
ISSUED AT 516 PM CST TUE DEC 10 2013

Only some mid to high clouds can be expected overnight as an upper
level disturbance crosses the central plains. A cold front will
also be crossing the central plains overnight. The NAM and GFSLAMP
and MAV appear to be in decent agreement with south winds shifting
to the north at HYS and GCK between 03z and 06z and then at DDC
around 06z. A brief period of gusty winds will be likely behind
this front, but by 12z these winds will subside back to around
10kts as an area of high pressure at the surface begins to build
into the area from the north.

&&

.PRELIMINARY POINT TEMPS/POPS...
DDC  12  27  13  42 /   0   0   0   0
GCK  10  28  13  42 /   0   0   0   0
EHA  13  32  18  48 /   0   0   0   0
LBL  13  30  15  46 /   0   0   0   0
HYS  10  27  12  39 /   0   0   0   0
P28  13  27  14  42 /   0   0   0   0

&&

.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

SYNOPSIS...JJohnson
SHORT TERM...JJohnson
LONG TERM...Umscheid
AVIATION...Burgert