Area Forecast Discussion
Issued by NWS Dodge City, KS
FXUS63 KDDC 230016
Area Forecast Discussion
National Weather Service Dodge City KS
716 PM CDT Wed Mar 22 2017
...Updated Aviation Section...
.SHORT TERM...(This afternoon through Thursday)
Issued at 1245 PM CDT Wed Mar 22 2017
Widespread stubborn stratus across the majority of SW KS this
afternoon, with partial clearing SW of a Syracuse-Liberal line.
Stratus will hold tough for most zones through sunset, and
temperatures will struggle into the lower to mid 50s across the
eastern CWA. Winds will trend SEly toward sunset and become gusty
as pressure gradient tightens in response to initial lee
cyclogenesis along I-25 in Colorado.
Any breaks in the clouds late today will quickly fill back in this
evening. Increasingly moist upslope flow will produce a lowering
stratus deck, with areas of fog and drizzle reducing visibility.
Do not currently expect the need for a dense fog advisory, as
models are not keen on forecasting widespread visibility of 1/4
mile, but will advise this evening`s shift to monitor. Areas of
drizzle are expected, along with some light rain showers, with
some places measuring 0.01-0.02 inch QPF. With thick clouds,
dewpoints rising, and SE winds elevated, temperatures tonight will
obviously be mild, holding in the 40s.
Thursday...Very windy and much warmer. Stratus, fog and drizzle
are expected to erode quickly by late morning, as the expected
strong surface cyclone deepens in eastern Colorado. South winds
will be quite strong in the afternoon, averaging 25-35 mph with
gusts near 45 mph. Expecting winds to remain below high wind
criteria, but some locations may flirt with it during the 5-7 pm
timeframe as 850 winds crank to 50 kts. Strong warm advection will
send temperatures soaring Thursday afternoon, with lower 80s
common. Moisture advection will also persist, with a dryline
expected to sharpen across the western counties through 7 pm.
Most of Thursday will be dry, as mounting instability is capped by
a strong inversion aloft. However, most models initiate convection
over or near SW KS by 7 pm, as intense forcing approaches from the
SW. Cape and bulk shear will support supercell thunderstorms by
6-7 pm, and the threat of severe weather is discussed in the new
SPC Day 2 convective outlook. The primary risk from thunderstorms
on the dryline will be focused across the western zones Thursday
evening, with hail up to golf ball size the primary threat.
Moisture will be less than optimal, and with the resulting higher
LCLs, storms may have a tendency to generate strong downdrafts
near 60 mph. With ambient 850 mb flow near 60 kts at the time of
initiation, the damaging wind threat will need to be monitored
closely, as this momentum may be easily transferred to the
surface. If supercells can initiate around sunset, they will have
an opportunity to become tornadic during the 7-9 pm time frame, as
they encounter a very strong low level jet.
As upper low intensifies over SE Colorado Thursday night (after
midnight), expecting thunderstorms and rainfall to end, as strong
dryslot surges into SW KS.
.LONG TERM...(Thursday night through Wednesday)
Issued at 245 PM CDT Wed Mar 22 2017
A very encouraging weather pattern is expected for a very dry
SW Kansas. An active parade of shortwave troughs is expected, with
multiple chances of rain forecast. Fortunately, from a forecasting
perspective, the models are in surprisingly good agreement with
shortwave timing (and the shortwave ridging and dry weather in
between) such that have rather high confidence in the grids and
forecast. Each of these systems will have sufficient access to
moisture to generate precipitation.
Friday...Cooler and showery. Strong 547 dm upper low near Syracuse
at 7 am will drift to near Medicine Lodge by 7 pm. While this
track will place the heaviest deformation zone rainfall well north
of SW KS, instability under the cold core aloft (-22C at 500 mb)
will generate scattered showers and thunderstorms during the
afternoon. With lowering freezing levels, small hail is likely
with the strongest storms. Also, pressure gradient behind the
departing cyclone late Friday will be impressive. Along with WFOs
Amarillo/Goodland, increased wind grids across the western
counties, with gusts near 50 mph likely. GFS progs 850 mb NW winds
of 50 kts on the backside of the departing cyclone, and a high
wind warning may be required.
Saturday...Dry and pleasant under strong transitory shortwave
ridging. Sunny, 60s, diminishing NW winds.
Sunday...Next shortwave in the train progged to be in NE New
Mexico at 7 am, and swing negatively-tilted fashion into SW KS by
7 pm. Scattered showers and thunderstorms expected. Noticed the
12z ECMWF is a bit slower with this shortwave`s progression, which
would place a threat for severe weather closer to the SE zones
Sunday afternoon and evening.
Monday...The pattern continues, dry and pleasant, under the next
shortwave ridge. Sunny, 60s, and a diminishing north wind.
Tuesday...This wave is modeled by the ECMWF to be quite strong and
possess strong forcing, with a similar setup as we are expecting
tomorrow. ECMWF would suggest severe weather potential next
Tuesday. 12z GFS digs this wave into a strong, slower closed low
over the SW US, and tracks this storm south of SW KS, delivering
widespread beneficial rainfall Thursday March 30. Any way you
slice it, multiple rain chances are coming, and we will take every
drop we can get!
.AVIATION...(For the 00Z TAFS through 00Z Thursday evening)
Issued at 712 PM CDT Wed Mar 22 2017
Low level moisture will continue to increase from the southeast on
continued 12 to 15 knot winds through the night tonight. Expect
ceiling to fall rapidly through MVFR into IFR and eventually LIFR
category at HYS, DDC, and GCK terminals. The duration of LIFR
conditions is expected to be around 3 to 5 hours with ceiling
below 300 feet and visibility at around 1/2 mile. There will
probably be some intermittent dense fog, however the wind speeds
should prevent a long duration of dense fog of 1/4 mile.
Nevertheless, aviation conditions will still be poor, and will not
likely improve until late morning or even early afternoon at HYS.
South winds will be quite strong during the afternoon as an
intense mid latitude cyclone gets closer to western Kansas.
Issued at 245 PM CDT Wed Mar 22 2017
Issued a fire weather watch for Hamilton, Stanton, and Morton
counties for Thursday afternoon and evening. Strong south winds
are expected, gusting near 40 mph, as strong low pressure develops
in eastern Colorado. Much drier air will prevail behind the
expected dryline, but exactly where the dryline sets up, and
exactly how dry dewpoints get behind the dryline, add uncertainty
as to whether red flag warning will be achieved. At any rate, the
fire weather watch matches with fire headlines from WFO Pueblo and
Goodland. High confidence on strong winds and at least marginally
dry humidity (15-20%) in SPC`s critical area on the Day 2 fire
weather outlook. With green-up yet to occur and wind gusts near
40 mph, any wildfires would spread rapidly. Additionally, any
thunderstorms that develop near the dryline Thursday afternoon
have the potential to produce dry lightning strikes, also
increasing the risk of fire danger and ignition.
.PRELIMINARY POINT TEMPS/POPS...
DDC 47 84 48 64 / 10 20 60 40
GCK 47 82 45 59 / 10 30 60 40
EHA 49 82 43 54 / 0 20 50 40
LBL 50 82 45 62 / 10 20 70 30
HYS 46 77 53 65 / 30 20 30 40
P28 50 81 55 73 / 20 20 40 30
Fire Weather Watch from Thursday afternoon through Thursday
evening for KSZ061-074-084.