Area Forecast Discussion
Issued by NWS Dodge City, KS
FXUS63 KDDC 181009
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DODGE CITY KS
409 AM CST Wed Dec 18 2013
...UPDATED LONG TERM...
.SHORT TERM...(Today and tonight)
ISSUED AT 1257 AM CST WED DEC 18 2013
Nearly zonal upper level flow over the Plains increases with lots
of high level moisture today and tonight. The stronger flow over the
Rockies will induce lower surface pressures in the lee of Rockies
with an increasing pressure gradient especially into south central
Kansas. South to southwesterly winds will increase after mid morning
mixing into the 15 to 25 mph range with lighter winds in parts of
far southwest Kansas closer to the surface trough. The winds will
again decrease tonight as the trough weakens as a diurnal response.
With increasing high level moisture, cirrus cloudiness will move
into western Kansas this morning then thicken and lower tonight with
mostly cloudy skies.
Highs today will be warmer than yesterday as 850mb temps warm from 7
Celsius to around 12-14 Celsius with a warm front. However, nearly
overcast high cloudiness will keep temperatures from really taking
off. Guidance temps in the mid 60s looks good. Lows tonight will
be warmer as the high level overcast clouds will minimize
radiational cooling. Lows in the low to mid 30s look good with the
warmest of 38 to 40 in the Coldwater to Pratt areas and east.
.LONG TERM...(Thursday through Tuesday)
ISSUED AT 403 AM CST WED DEC 18 2013
A dramatic change to the sensible weather is expected beginning
Thursday, followed by increasing confidence in winter weather
impacts heading into the weekend.
Both the GFS and ECMWF continue to be in agreement on the main
synoptic pattern evolution through the weekend. Another arctic surface
anticyclone will dive into the U.S. Plains Thursday with a cold
front likely moving through western and central Kansas during the
morning and early afternoon on Thursday. Falling afternoon
temperatures and increasing stratus clouds can be expected. The
models indicate the stronger winds won`t be right during frontal
passage but rather later in the evening into the overnight in the
subsident post frontal airmass.
Of probably even more concern will be potential for wintry
precipitation by Saturday evening. The numerical models continue to
show the pattern of a warm front creating potential for isentropic
lift across the southern plains late in the day. A significant
thermal gradient will be in place as a cold pool advances aloft,
enhancing mid level frontogenesis somewhere along the Kansas and
Oklahoma line. The ECMWF and GFS seems to suggest a brief period of
drizzle possible Saturday, but rapidly changing over to snow based
on the thermal top down forecast sounding profiles. Given that the
models already produce convection across eastern Oklahoma, a fair
amount of confidence exists in the pattern being basically
correct. The ECMWF was less aggressive that the GFS is in
determining snow amounts, however taking the least common snow
amounts, a couple of inches are possible from areas near MINNEOLA to
Medicine lodge and perhaps even farther north near Greensburg and
Pratt, depending on where the best frontogenesis occurs. Minor
adjustments to the forecast QPF and snow amounts were added,
focusing on accumulation along the KS/OK line.
Temperatures will likely return to near normal for late December
(highs in the 40s) briefly by Monday. Another Pacific cold front
appears poised to move into the Great Plains after Tuesday.
.AVIATION...(For the 06Z TAFS through 06Z Wednesday night)
ISSUED AT 1130 PM CST TUE DEC 17 2013
VFR conditions will continue today and tonight. Nearly zonal upper
level flow will increase over the Rockies with increasing high
level moisture. This will cause a surface low pressure trough to
deepen in the lee of the Rockies with a strong pressure gradient
into much of south central Kansas along with overcast cirriform
cloud cover. Southwest winds around 10kt will increase to 14-26kt
after mixing gets going by mid to late morning. Winds then become
light again after 23Z. Overcast high level cirrus cloudiness will
continue overnight and lower to about 500mb.
.PRELIMINARY POINT TEMPS/POPS...
DDC 65 34 47 17 / 0 0 0 0
GCK 65 31 46 16 / 0 0 0 0
EHA 67 35 56 21 / 0 0 0 0
LBL 67 33 53 21 / 0 0 0 0
HYS 65 31 42 15 / 0 0 0 0
P28 66 40 59 21 / 0 0 0 0