Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Dodge City Kansas
209 PM CST Sat Dec 7 2013
..updated long term discussion...
issued at 1020 am CST Sat Dec 7 2013
Water vapor imagery and 12z upper air analysis indicate a
southwesterly flow aloft prevailing across the western High Plains.
Meanwhile, an upper level trough of low pressure is swinging
southeast out of the Pacific northwest into the Great Basin region.
Near the surface, a large area of high pressure extends from the
Dakotas southward into much of Kansas. Extremely dry air has settled
across the area with surface dewpoints just below 0f across central
and much of southwest Kansas.
Short term...(this evening through sunday)
issued at 120 PM CST Sat Dec 7 2013
Short range models indicate the upper level trough across the
intermountain west turning more eastward into the northern and
central rockies tonight setting up the possibility for light snow
development across central and portions of western Kansas into
Sunday. As the upper level shortwave approaches, the prevailing
southeasterly flow near the surface will begin to draw moisture
up into the region with dewpoints climbing well above 0f,
potentially nearing 10f across south central Kansas. While,
moisture slowly increases overnight, surface low pressure is
projected to move quickly eastward across the Colorado rockies
into eastern Colorado by mid day Sunday. This will set up increased
low level forcing across central Kansas as the surface high in the
northern plains is slow to move into the Great Lakes region.
Additionally, upper level support will be more favorable as a
strong +110kt jet lifts northeast across central and southwest
Kansas through the period. However, NAM/GFS model soundings Show
Low precipitable water values of well under half an inch with profiles slow to
saturate, potentially resulting in limited snow accumulations.
The best chance for accumulating snow looks to be across central
Kansas near the I-70 corridor where lift/moisture looks to be the
most favorable. An inch or so may be possible here, otherwise,
accumulations are expected to be generally less than an inch.
Temperatures will be somewhat warmer from this morning going into
early Sunday morning as slightly warmer air advects northward into
western Kansas while surface dewpoints climb above 0f. Expect
lows just below 10f across west central Kansas to the lower
teens(f) across south central Kansas. Warmer temperatures can be
expected Sunday as the low level southerly flow continues to draw
warmer air northward into southwest Kansas. However, increased
cloud cover and lingering snow pack will hinder temperatures from
climbing too much. Look for highs only up into the 20s(f) with a
few 30s(f) possible close to the Oklahoma border.
Long term...(sunday night through saturday)
issued at 208 PM CST Sat Dec 7 2013
The amplified upper level flow pattern over North America on Monday
will dampen out with time and become nearly zonal by late in the
week. The cold airmass over western Kansas will get a reinforcing
shot late Sunday and Sunday night behind a shortwave trough that
will be exiting the Central High plains. The next shortwave will be
dropping south through The Rockies Sunday night before ejecting
eastward through the Southern Plains on Monday and Monday night. The
GFS and European model (ecmwf) develop a little light snow with this shortwave but
mainly keep it south of the Oklahoma border Monday night. This
system could produce a few flurries in the Coldwater and Medicine
Lodge areas but given the low probability for measurable
precipitation, will leave the forecast dry for now.
Another fast moving shortwave trough will drop out of Canada into
the northern plains and Midwest on Wednesday. This will send a weak
shot of cooler air into western Kansas so wednesday's high
temperatures will be fairly similar to Tuesday. A more significant
warmup, at least closer to normal temperatures, will occur on
Thursday and Friday as westerly flow with shortwave ridging
develops over the Central Plains.
By the weekend the models show another wave moving out of The
Rockies and into the plains. This will push another cold front south
across western Kansas. Chances for precipitation look fairly low
with this wave.
Aviation...(for the 18z tafs through 18z Sunday afternoon)
issued at 1100 am CST Sat Dec 7 2013
Although low level stratus will persist across western Kansas
through tonight, VFR conditions will prevail at all taf sites
through this evening. MVFR cigs will be possible in the vicinity of
all the taf sites generally after 06z as the stratus deck begins
to lower during the overnight hours. Brief periods of MVFR vsbys
will be possible mainly west of kddc late this afternoon into this
evening as areas of light snow will be possible across portions
of southwest Kansas. However, significant accumulations are not
expected. As for winds, surface high pressure in the northern
plains will drift slowly eastward tonight as surface low pressure
moves into the western High Plains from the west. As a result,
east to southeasterly winds of 5 to 15kt this afternoon will
become more south to southeasterly this evening at around 10
Preliminary point temps/pops...
ddc 10 22 6 19 / 30 10 10 10
gck 9 20 4 19 / 20 10 0 10
eha 10 33 6 18 / 20 10 10 10
lbl 10 30 6 19 / 20 10 10 10
hys 8 20 5 19 / 70 50 10 10
p28 12 25 11 22 / 40 10 10 10