051
FXUS63 KDDC 290639
AFDDDC

Area Forecast Discussion
National Weather Service Dodge City KS
139 AM CDT Tue Sep 29 2026

.KEY MESSAGES...

- A flood watch remains in effect for much of western Kansas
  through Thursday.

- Numerous showers and a few t-storms will spread eastward today
  and become more widespread in the afternoon.

- Heavier rain is forecast for tonight into Wednesday, with
  widespread totals of 1 to 3" (lower amounts in south central
  Kansas). Localized amounts of greater than 3" to as much as 4 +"
  are possible.

- A tornado or two can`t be completely ruled out Wednesday
  afternoon.

- Temperatures will likely dip into the 40s Saturday morning.

&&

.DISCUSSION...
Issued at 1213 AM CDT Tue Sep 29 2026

A deep upper level trough over the Desert Southwest will merge
with the remnants of Hurricane Polo early this week and then
move into southwest Kansas. Ahead of the system, widespread
showers are expected today, with rain spreading from west to
east. Some thunder could occur with the initial showers as some
potential instability will exist. Preciptable water values (up
to 1.8") are forecast to increase to above the 99th percentile
given the deep tropical moisture.

Looking back through history, heavy rains from the remnants of
tropical systems are very rare across western Kansas. Atlantic-
Gulf systems tend to curve to the east of the high plains while
Pacific storms typically dry out over the mountains, with only
light to moderate rain occurring. In this particular case, the
tropical system will get steered to the north and east and
accelerate due to the approaching upper level storm, leaving
less time for weakening. Historical tropical systems that
weakened and then dumped heavy rain across the high plains
include the Galveston Hurricane of 1900 (4 to 6" from north of
Dodge City into eastern Nebraska and southern Minnesota) and
the September hurricane of 1919 (8 to 14" across parts of
western and northern Kansas), both of which were Atlantic/Gulf
storms.

By tonight the remnants of Hurricane Polo will be absorbed into
the large upper trough and accelerate northeastward across the
southern Rockies into the southern high plains. The heaviest
rain will spread northward Tuesday night into Wednesday and end
from south to north Wednesday afternoon and night. Although the
various ensemble means indicate widespread 1 to 3" rains, with
highest along and west of a line from Dodge City to Hays, there
will likely be narrow corridors in areas of training that get a
lot more. This is supported by the grand ensemble 75th and 90th
percentiles for rain amounts over the period from Tuesday
through Thursday of 3 and 4" respectively. Thus, the flood watch
was maintained for the Tuesday to Thursday time frame.
Additional periods of rain are likely Wednesday night and
Thursday as the upper low will be very slow to move away from
the high plains.

T-storms are expected to form Wednesday afternoon in the wake of
the heavy rain as the surface low and mid level dry intrusion
arrive from the southwest. If modest insolation occurs and
temperatures rise at least into the upper 70s, along with 70F
dewpoints, then any convective inhibition would vanish, leading
to isolated t-storms. Given the very warm temperatures at upper
levels, which is characteristic of early autumn, lapse rates
will not be supportive of very large hail; but marginally severe
hail and damaging winds can`t be ruled out. However, given the
increasing vertical wind shear ahead of the surface low, with
with low level southeasterlies and moderate southwesterlies at
mid levels, a few tornadoes can`t be ruled out. The only
significant tornado in western Kansas associated with the
remnants of a tropical system occurred on 15 August 1880 in
Dighton when 1 person was killed; but this was also an Atlantic-
Gulf storm. There is no record of this officially; but local
office research uncovered the event.

The coolest air of the season will arrive Saturday morning as an
upper level trough traverses the northern tier of states and
pushes a cold front southward. Expect temperatures to fall into
the 40s across much of western Kansas by sunrise Saturday as
winds become light. This is only slightly below the
climatological average of 50. One limiting factor for
temperatures is all the rain we will receive prior to the cool
air arrival, resulting in higher dewpoints and less potential
for radiational cooling. This will not be a very cold air mass
by late September standards; but it will be a marked change from
the late summer heat.


&&

.AVIATION /06Z TAFS THROUGH 06Z WEDNESDAY/...
Issued at 1123 PM CDT Mon Sep 28 2026

Low level moisture transport will continue ahead of an upper
level trough over the Desert Southwest. Large scale ascent and
marginal convective instability will result in shower and
t-storm development from west to east on Tuesday, with CIGS
gradually lowering from VFR to MVFR. The rains will become more
widespread later in the day and some reduction in visibilities
is possible in the heavier showers. Expect winds to gradually
veer from southeast to south early in the period, with speeds
lowering to the 8-12 kt range.

&&

.DDC WATCHES/WARNINGS/ADVISORIES...
Flood Watch from 7 AM CDT /6 AM MDT/ this morning through
Thursday evening for KSZ030-031-043>046-061>064-074>078-
084>087.

&&

$$

DISCUSSION...Finch
AVIATION...Finch