Area Forecast Discussion
Issued by NWS Dodge City, KS
FXUS63 KDDC 052245
Area Forecast Discussion
National Weather Service Dodge City KS
445 PM CST Mon Dec 5 2016
.SHORT TERM...(This afternoon through Tuesday)
Issued at 1130 AM CST Mon Dec 5 2016
A pleasant afternoon for early December standards, with
temperatures warming well into the 50s, and lower 60s west of
Dodge City. S/SW winds gusting to 30-35 mph as of noon will
diminish rapidly late this afternoon as pressure gradients
weaken. Strong, but dry cold front will reach the northern zones
around 6 pm.
Tonight...Strong north winds. Wind velocities look to peak around
midnight, averaging 20-30 mph (gusts 35-40). Winds will remain
strong tonight, despite the nocturnal timing, given strong
cold/dry advection. North winds will relax toward sunrise, but
remain elevated enough to prevent full radiational cooling. Lows
Tuesday morning ranging from the teens in Hamilton county, to the
upper 20s in Barber county. Wind chill factors at sunrise ranging
from near 5 at Syracuse to the teens at Medicine Lodge. No stratus
expected given the arrival of the very dry air.
Tuesday...Much colder. Quite the airmass change across SW KS, with
850 mb temperatures today near +9C crashing to near -6C Tuesday.
Afternoon readings reduced to the 30s for most locales. The good
news: much less wind. 1024 mb surface high builds south into SW KS
through the day, with winds becoming light and variable by
afternoon. Midlevel clouds will increase rapidly ahead of incoming
shortwave by 6 pm, ahead of incoming shortwave, as shown by model
RH cross sections.
.LONG TERM...(Tuesday night through Monday)
Issued at 220 PM CST Mon Dec 5 2016
...Arctic cold will visit SW Kansas Wednesday and Thursday...
All model guidance has trended drier with their 12z runs today,
with less snow expected Wednesday compared to previous forecasts.
This was never expected to be a significant heavy snow event for
SW KS by any stretch, but still, this forecast trimmed the modest
forecast snow amounts we had going down considerably. This result
isn`t terribly surprising, and there are three main reasons for
it. 1) Shortwave near Grand Junction at 6 am Wed is very
progressive, racing to SW Kansas at noon, and into eastern Kansas
Wednesday evening. This is way too fast to allow gulf moisture to
be entrained into the strong jet dynamics. 2) The projected track
of the shortwave has shifted slightly north with the model
consensus, which only hinders snowfall coverage and amounts in our
CWA. 3) Perhaps most critically, incoming arctic airmass Wednesday
will not only be very cold, but also very dry, with dewpoints
cratering to the single digits and teens. This dry lower
atmosphere will make any significant snowfall difficult to
achieve, with much lost to evaporation and virga.
So, for Wednesday...reduced stratiform snow to scattered snow
showers, but did keep likely snow showers near the I-70 corridor
centered on the 6am-noon Wed time frame. Still have 1-2 inches in
the grids for the northern counties (Scott, Lane, Ness, Trego,
Ellis) with the higher amounts favoring the N/NW portions of these
counties. These new coordinated snow totals match well with WFO
Goodland. All other locations, less than one inch, ranging down to
a passing flurry or nothing along the Oklahoma border. Also after
coordinating with GLD, opted to maintain a mention of blowing snow
given the arctic airmass yielding fluffy windblown dendrites.
Still possible a winter weather advisory may be needed for the
northern zones for the Wednesday morning commute to work and
school, but the primary impacts will clearly be in WFO Goodland`s
CWA (NW Kansas).
Wednesday...Much colder. Arctic air arrives, with 850 temperatures
falling to near -11C by afternoon and thickness at Dodge City
falls to 521 dm. This translates to most locations stuck in the
20s. GFS displays strong cold advection continuing through
afternoon, so steady temperatures or a non-diurnal slow downward
afternoon temperature curve is possible. In other words, it will
be cold. NE/N winds gusting to 30 mph or higher will create wind
chill factors in the single digits and teens. Partial clearing by
sunset as subsidence behind departing shortwave arrives.
Wednesday Night/Thursday Morning...COLD! Impressive arctic surface
high near 1050 mb centered in Alberta Thursday morning, with an
expansive arm of the surface ridge bridging down the front range
and the high plains. Cold advection will continue all night
through sunrise, as a NW wind near 10 mph persists. With a clear
sky, this will prevent temperatures from falling to their full
potential. That said, single digits will be common, with wind
chills of -10 to zero. This is not our advisory criteria (-15),
but very uncomfortable to say the least.
Thursday...Still cold. Massive arctic high pressure ridge progged
by GFS to extend from Alberta to central Texas Thursday afternoon,
with the cold airmass remaining locked over SW KS. Even with full
sun, GFS shows little if any recovery at 850 mb Thursday, still
near -10C. All locations expected to remain below freezing all day
Friday morning...One more cold morning, 5-15 degrees.
Friday and Saturday...Arctic air is flushed out, lee troughing
returns, and temperatures moderate quickly. Back to the 30s and
40s Friday, and 40s and 50s Saturday. Unfortunately, SW KS will
remain dry throughout this forecast period.
.AVIATION...(For the 00Z TAFS through 00Z Tuesday evening)
Issued at 500 PM CST Mon Dec 5 2016
VFR. Fropa tonight w/ N winds inc 15-25 kt dec during the afternoon.
.PRELIMINARY POINT TEMPS/POPS...
DDC 24 38 21 29 / 0 0 20 40
GCK 20 37 20 27 / 0 0 30 40
EHA 21 36 21 29 / 0 0 10 20
LBL 23 38 23 31 / 0 0 10 20
HYS 23 36 20 26 / 0 0 30 60
P28 29 42 26 34 / 0 0 10 20