104
FXUS63 KDDC 151035
AFDDDC

Area Forecast Discussion
National Weather Service Dodge City KS
535 AM CDT Sun Sep 15 2024

.KEY MESSAGES...

- Hot this afternoon across far southwest Kansas with highs well
  into the 90s.

- Storm system Tuesday-Tuesday Night to bring increased
  thunderstorm potential, however severe weather risk is very
  low (Marginal 1 of 5 Risk area confined to neighboring eastern
  Colorado).

- Eyes on a second, perhaps stronger storm system late in the
  week centered on Friday-Saturday time frame with another round
  of numerous thunderstorms and perhaps severe weather risk..

&&

.DISCUSSION...
Issued at 353 AM CDT Sun Sep 15 2024

The overnight water vapor loop and RAP objective analysis fields
showed that our southwest Kansas region was within a narrow positive-
tilted upper level ridge axis extending from roughly the Texas
Panhandle through Kansas into the Great Lakes region. Upstream of
southwest Kansas the pattern was a diffuse southwest flow aloft with
weak mid and upper tropospheric winds. A trough in the main polar
westerlies was well away from our region entering the Pacific
Northwest region. This feature will eventually become a player in
our sensible weather as we head into Tuesday and beyond.

For today, more above to well-above normal temperatures will occur
this afternoon as the lower troposphere remains very warm within the
aforementioned ridge axis. Official temperature grids will be
roughly 75th percentile NBM given the antecedent dry conditions over
the past few weeks. 75th percentile NBM yields 95-96F across the
Elkhart-Hugoton-Liberal corridor of far southwest Kansas. A leeside
trough convergence axis will develop across the usual areas of far
southeast Colorado. Scattered high-based showers and thunderstorms
are expected to form in this region of southeast Colorado, however
storms are expected to be sub-severe given paltry SBCAPE and poor
mid-level winds. Regardless, we will have some 15-20 POPs across our
far western CWA adjacent CO border in the event one or two of these
storms sneak far enough east into far western Kansas.

As we head in to tonight and Monday, a southern branch of the
westerlies will strengthen across the Southwest as the main trough
axis begins to dig down the West Coast. Ahead of the trough across
the Central Plains early Monday, most deterministic models show a
north to south axis of increasing weak warm frontogenesis,
supporting the development of elevated thunderstorms within this
axis of forcing for ascent, mainly across north central Kansas.
There is both global and high-resolution model support for this
early Monday morning activity (HREF 75th percentile 6-hr QPF 0.10 to
0.25" mainly just to the east of our CWA from Beloit south down to
Kingman, KS. There is enough of a signal to have some 20-30 POPs
adjacent WFO ICT forecast area early Monday morning. A nebulous exit
region of the southern branch jet is shown to nose into the TX-OK
Panhandle and adjacent southwest KS later in the day Monday, which
may interact with an outflow boundary from any of the morning
convection to enhance low level convergence for possible renewed
surface-based thunderstorm development. This is something we will
keep watching, and we will have some 20 POPs for most of the
forecast area Monday afternoon. The vertical wind shear profile
would support loosely organized strong to perhaps a marginal severe
storm or two (0-6km bulk shear magnitude of 25-30 knots), however
coverage of any afternoon convection Monday would be quite sparse if
any storms even form at all.

The best chance for more widespread showers and thunderstorms will
come Tuesday Night as the main body of the upper level trough moves
out of the Rockies and across the Northern-Central Plains. Global
models and ensemble systems continue to slowly come into better
agreement of at least a loosely organized convective system or two
moving out of Colorado and across much of the western half of Kansas
Tuesday Night. Given the increased model and ensemble system
continuity, the NBM POPs continue to increase for Tuesday Night, up
to 50-60% across much of western and central Kansas. The forcing for
ascent just ahead of the upper level system will likely progress
fast enough such that heavy rainfall is fairly unlikely, hence
latest 00Z run of 100-member Grand Ensemble 25-75th QPF totals are
mainly in the few hundredths of an inch to three-tenths of an inch
range. Isolated high-end amounts of up to three-quarters of an inch
cannot be ruled out (based on 95th percentile), with the best area
for an isolated amount that high generally west of Highway 83.

The Tuesday storm system will lift northeast rapidly across the
Dakotas mid-week, but the larger scale trough axis will remain
across the West with the next wave expected to rotate around the
base of the larger trough axis late in the week (Fri-Sat). This will
support chances for more organized thunderstorms across southwest
Kansas either or both days Friday and/or Saturday with an associated
severe weather risk, perhaps. Details of this 2nd system are still
quite unclear given model uncertainty beyond +5 days, so keep
checking back for updates.

&&

.AVIATION /12Z TAFS THROUGH 12Z MONDAY/...
Issued at 533 AM CDT Sun Sep 15 2024

South to southeast wind will continue this TAF period along with
widespread VFR flight category in the ongoing warm pattern.
Isolated to widely scattered thunderstorms near the Colorado
line later this afternoon and early evening are not expected to
approach any of the terminals, including GCK.

&&

.FIRE WEATHER...
Issued at 353 AM CDT Sun Sep 15 2024

Hot and dry conditions will develop across mainly far southwest
Kansas this afternoon. As temperatures warm into the mid 90s for
a few hours, the relative humidity is forecast to fall into the
17 to 22% range mainly along and west of Highway 83 and along
and south of Highway 50. Winds in this region will likely range
15 to 20 mph from the south-southeast with gusts at times around
25 mph. The combined conditions will likely support elevated to
perhaps near-critical fire weather behavior for a few hours
until sunset.

&&

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

&&

$$

DISCUSSION...Umscheid
AVIATION...Umscheid
FIRE WEATHER...Umscheid