826
FXUS63 KDDC 201940
AFDDDC

Area Forecast Discussion
National Weather Service Dodge City KS
240 PM CDT Fri Sep 20 2024

.KEY MESSAGES...

- 20-40% chance for thunderstorms late today and evening. Main
  hazard from a few of these storms will be wind gusts of 50 to
  60 mph and hail.

- Rain, heavy at time likely (>70%) across southwest Kansas this
  weekend. There is a 50 to 70% chance of 24 hour rainfall
  totals exceeding 2 inches from 1 pm Saturday to 1 pm Sunday
  north of Dodge City, especially near the I-70 corridor.

- Unseasonably cool air returning over the weekend period. There
  is a 40 to 80% chance for highs climbing only in the 50s on
  Sunday, with the highest confidence (60-80%) west and north
  of Dodge City.

&&

.DISCUSSION...
Issued at 223 PM CDT Fri Sep 20 2024

There is a 20-40% chance of thunderstorms this afternoon and
early this evening as a -8C 500mb trough lifts northeast from
New Mexico into southwest Kansas, and a surface warm front moves
northward across the region toward Nebraska. The current severe
weather potential appears low, given that the short term
ensemble shows less than a 30% chance for MUCAPE >500 and 0-6 km
shear >30 knots through 03Z Saturday. However, based on steep
low level lapse rates and downdraft CAPE after 21z today, a few
storms may still be capable of producing wind gusts of 50-60
mph and isolated hail. Mean precipitable water values from this
mornings ensembles range from 1 to 1.25 inches, placing them
between the 75th and 90th percentile for this time of year in
the Dodge City area. As a result along with gusty winds and
hail...isolated heavy rainfall is also possible.

While widespread heavy rainfall is not expected tonight,
conditions will change as we head into the weekend.

Over the weekend widespread rainfall will be likely (+80%),
mainly from late Saturday through early Sunday. This is due
improving large synoptic lift (isentropic lift and 850mb warm
air advection north of a cold front situated across northwest
Oklahoma and the Texas Panhandle) ahead of an upper low as it
moves into the Central Rockies and starts to encounter this
abundant moisture over southwest Kansas. From this widespread
rain...a large area of southwest Kansas could see rainfall
totals in excess of 1 inch this weekend given the abundant
moisture that will be present across southwest Kansas. At 00Z
Sunday the mean precipitable water values from the short term
ensembles east of Highway 83 are forecasted to exceed 1.5",
which is above the 90th percentile according to Dodge City
sounding climatology for this time of year. The latest NBM
chance for rainfall exceeding 1 inch in a 24hour period have
been rising over the past several days, with current chances
ranging from 60 to 90%, the highest being north of Dodge City.
Near the I-70 corridor, there is a 50 to 70% chance of 24-hour
rainfall totals exceeding 2 inches by 1 pm Sunday.

Areas north and northwest of Dodge City should closely monitor
this developing rainfall event, as watches or warnings may be
issued for Saturday night into early Sunday.

Along with the widespread rainfall expected this weekend, a
strong cold front will cross southwest Kansas during the day on
Saturday. As the front passes, 850mb temperatures, currently
near 24C at 12Z Saturday, are forecast to drop to around 20C by
00Z Sunday, accompanied by gusty north winds. These 850mb
temperatures will continue to fall, reaching the single digits
by 18Z Sunday. The short term ensemble spread of 850mb
temperatures is small, averaging 5C or less, giving high
confidence (50-70%) that an unseasonably cold air mass will
settle over western Kansas as early as Sunday morning.

Current NBM guidance suggests cool, fall-like highs in the 60s.
However, there`s a strong indication that temperatures may be
even cooler, with highs only in the 50s possible based on
expected cloud cover and ongoing precipitation. Confidence in
highs only reaching the 50s ranges from 40 to 80%, with the
highest confidence (60-80%) west and north of Dodge City. For
areas north and west of Garden City, there`s a 30-50% chance
that highs may not rise much above 50F. Given these cooler
temperatures and a gusty north wind exceeding 40 mph at times,
wind chills may drop to 40-45F at times during the day Sunday.

Skies will clear Sunday night as the upper level low weakens
and moves east across the Central Plains. A cool dome of high
pressure will cross western Kansas, leading to light winds early
Monday morning. Clear skies and light winds will create
favorable conditions for cooler than expected/forecast
temperatures. There is a 30-40% chance that lows will fall to
35-40F west of Highway 83, with lows of 40-45F possible (40-70%)
as far east as Hays, Greensburg, and Ashland.

These cool temperatures will linger through the first half of
next week as another upper level trough crosses the Central
Plains. Although moisture will be limited, any precipitation
early next week will likely be confined to far southwest Kansas.
By late week, a gradual warming trend will bring temperatures
back to more seasonal levels.


&&

.AVIATION /18Z TAFS THROUGH 18Z SATURDAY/...
Issued at 1219 PM CDT Fri Sep 20 2024

At 17Z this Friday afternoon an area of weakening thunderstorms
were accompanying an upper level trough as it moves northeast
toward extreme southwest Kansas. These showers/thunderstorms
will spread across southwest Kansas between 20z today and 01z
Saturday with only a 20% chance or less for any of these
thunderstorms to impact the Dodge City and Liberal areas. Will
therefore include a period of VCTS in these tafs late today to
account for this. The next better chance for precipitation will
be after 15z Saturday as a stronger upper low/trough approaches
from the west. Ceilings this afternoon will be at or above
8000ft AGL. Winds outside these thunderstorms will be primarily
south southeast at 10 to 15 knots today.

&&

.DDC WATCHES/WARNINGS/ADVISORIES...
None.

&&

$$

DISCUSSION...Burgert
AVIATION...Burgert