Area Forecast Discussion
Issued by NWS Dodge City, KS
FXUS63 KDDC 220345
Area Forecast Discussion
National Weather Service Dodge City KS
1045 PM CDT Tue Mar 21 2017
...UPDATE TO SYNOPSIS...
Issued at 1043 PM CDT Tue Mar 21 2017
WV imagery indicates an upper level ridge of high pressure transitioning
eastward across the Central Plains. Near the surface, a broad area of
high pressure is shifting slowly eastward across the Great Lakes.
.SHORT TERM...(This afternoon through Wednesday)
Issued at 1120 AM CDT Tue Mar 21 2017
Much cooler air filtering into Kansas through this afternoon, but
certainly nothing unusual for March. Stratus has been broken
across the northern zones, and not as widespread as expected,
allowing most locations to get within a few degrees of 60 this
afternoon. NE winds of 15-25, gusting near 30 mph, will continue
into the evening hours.
Consensus of short term models and forecast soundings indicate
stratus to become widespread tonight. This makes sense as easterly
upslope flow of 10-20 mph maintained overnight. Fog and drizzle
are not expected tonight. With the thick clouds and easterly flow,
added several degrees to Wednesday morning low temperatures. Most
locations will hold well above freezing, in the mid to upper 30s.
For many days now, models have been consistent in generating light
rain showers overnight tonight, as weak vorticity maxima aloft
pass over the post frontal upslope. Models are very loath to
generate much QPF with such limited forcing. As such, purposely
limited pop grids tonight to slight chance (<25%) and QPF to 0.01
inch. Don`t expect much; beneficial rainfall is not expected.
Wednesday...Cool airmass remains wedged into at least the eastern
1/2 of SW Kansas, keeping temperatures restricted to the 50s near
and east of Dodge City. Modification of the cooler airmass
expected west, where locations near the Colorado border will warm
well into the 60s. These temperatures will be dependent on stratus
evolution, and may end up being too warm across the east. Initial
lee side cyclogenesis along I-25 Wednesday afternoon will induce a
SE wind of 15-25 mph with some higher gusts.
.LONG TERM...(Wednesday night through Tuesday)
Issued at 225 PM CDT Tue Mar 21 2017
Three distinct opportunities for badly-needed rainfall are
apparent in the long term forecast: 1)late Thursday through
Friday, 2) on Sunday, and 3) next Tuesday (one week from today).
A progressive series of strong shortwaves will keep the weather
active across SW KS through the next week, and it appears each one
will have a sufficient moisture supply to generate precipitation.
Thursday...Very windy and much warmer. Widespread stratus and
drizzle expected during the morning hours. Strong closed but
progressive upper low expected to be near Grand Junction, Colorado
by 7 pm, with a strong vorticity max and jet max rotating around
the base of the trough through New Mexico, aiming for SW KS. The
first and primary impact will be very strong south winds, in
response to strong cyclogenesis in eastern Colorado. Strongest
gradient is progged during the sunset/evening time period, when
GFS cranks 850 mb winds to near 60 kts. Strongest gusts, as high
as 55 mph, expected during the late afternoon. Intense warm
advection will result in a rapid warmup to near 80 for most
locations. The south winds will also facilitate strong moisture
advection from the Gulf of Mexico into central Kansas, with a
dryline firming up across SW KS during the afternoon. Intense
forcing will overtake this dryline during the late afternoon to
early evening hours, with shear/CAPE profiles favorable for
supercells and severe weather. Quality of moisture return, and the
timing of initiation (late evening as opposed to late afternoon)
will be the determining factors regarding the severity of the
expected thunderstorms. 12z ECMWF shows convection erupting across
the western CWA Thursday afternoon, then diminishing overnight as
the dryline retreats. Unfortunately, it appears our rainfall
prospects may shut down overnight into Friday morning, as a strong
dryslot wraps into SW KS, ahead of a strong 545 dm upper low near
Lamar. With this evolving synoptic setup, rainfall coverage will
not be as widespread as desired. Model blended pops grids came
down some this run, but are likely still too high. The downward
trend is in the right direction, and future trims are likely.
Friday...Closed low tracks SE into NW Oklahoma, with wraparound
rain showers possible. Again, rain coverage will not be what is
desired on Friday, as the deformation axis precipitation is
consistently being forecasted to remain north of SW KS. Again,
shower coverage has been reduced on Friday with this forecast.
Saturday...Sunny, dry and pleasant under shortwave ridging.
Modest NW winds.
Sunday...Active wave train continues, with a strong negatively
tilted shortwave spreading into Kansas during the day. Models are
fairly generous producing QPF with this system, particularly
across the eastern zones. A potent severe weather setup may evolve
for south central Kansas, which may involve the Barber county
Monday...Dry and north winds again, under transitory shortwave
Tuesday...More active weather likely. All models generate
additional precipitation, with ECMWF depicting a weaker shortwave
and 12z GFS showing a strong closed low in New Mexico. Either way,
the rain chances will continue, which is a good thing.
.AVIATION...(For the 00Z TAFS through 00Z Wednesday evening)
Issued at 647 PM CDT Tue Mar 21 2017
Stratus clouds will overspread the southwest Kansas region tonight
as winds shift around to the southeast in the low levels. The
remnant cold, dry Canadian high was a bit stronger than previous
forecast, which will actually delay the onset of stratus at HYS,
and keeping it in the MVFR category through the period. In fact,
all three terminals DDC, GCK, HYS will have ceilings in the MVFR
category. Lower level moisture supporting IFR category will
eventually move into southwest Kansas, but not until Wednesday
.PRELIMINARY POINT TEMPS/POPS...
DDC 38 57 46 80 / 20 10 20 20
GCK 37 62 45 80 / 20 0 10 30
EHA 39 67 46 78 / 20 10 10 30
LBL 38 64 45 78 / 20 10 10 30
HYS 36 54 45 76 / 20 10 20 20
P28 42 57 49 79 / 10 10 20 20