996
FXUS63 KGLD 280932
AFDGLD

Area Forecast Discussion
National Weather Service Goodland KS
332 AM MDT Mon Sep 28 2026

.KEY MESSAGES...

- Southerly winds of 20-25 mph with gusts up to 40-45 mph is
  possible for portions of the eastern Colorado Counties this
  morning into the early afternoon hours.

- Chances of rain become widespread late tonight, increasing to
  as much as a medium to likely (60-90%) chance by Tuesday
  afternoon.

- Heavy rain is expected by Tuesday afternoon, especially
  along/south I-70 and along/east US-83, where 1.5 to 2.0 inches,
  or more, are expected by Wednesday morning.

- A Slight (level 2/4) to Moderate Risk (level 3/4) of isolated
  flash flooding is possible across the region on Tuesday and
  Tuesday night, especially for the southern-most forecast
  counties in east-central Kansas that received heavy rainfall
  this past week.

&&

.SHORT TERM /THROUGH TUESDAY NIGHT/...
Issued at 326 AM MDT Mon Sep 28 2026

Areas of light fog and some patchy dense fog this morning will
dissipate later this morning as winds increase. A weak wave moving
over the Colorado Rockies has kicked off some scattered showers over
northeast Colorado and the Nebraska Panhandle. This activity will
dissipate by mid-morning as the wave lifts north.

This weeks wet pattern is starting to take shape today water vapor
satellite imagery shows a negatively trough digging southwards
across California this morning and Hurricane Polo spinning off the
Baja coast. In addition, a plume of sub-tropical/tropical moisture
(remnants of Odalys) is being drawn up across southern California
and into the Desert Southwest between the aforementioned trough and
hurricane. Through the remainder of today, this trough will "close
off" before moving into the lower Colorado River Valley. Hurricane
Polo will move across Baja and rapidly fall apart as it moves
inland....eventually merging with the more dominant southwesterly
flow aloft. Most of the mid to long-range models are in fairly good
agreement with the timing and the position of the mid/upper trough
as it moves across the western states, though the NAM does dig the
trough a bit further south. By early Wednesday, the models start to
diverge more on the placement of the mid/upper low with the GFS and
Canadian keeping the low further south. The solutions further
diverge as the GFS lifts the low into the Plains more quickly before
transitioning into an open wave later in the week. Regardless of
which solution ultimately prevails, the Tri-State area can expect to
see another widespread rainfall event this week...beginning Tuesday
morning and continuing through Thursday.

For today into tonight... A tightening pressure gradient over the
High Plains, as the lee trough deepens, will result in increasing
south to southeasterly surface winds this morning and afternoon. The
strongest winds will be along the CO/KS border where southerly winds
may gust as high as 40-45 mph. A weak shortwave trough will move
through the broader southwesterly flow aloft and may help to kick
off some thunderstorms over northeast Colorado. CAM models differ
quite a bit on CAPE values this afternoon, but given increasing
cloud cover through the day limiting instability, expect the
thunderstorms to initiate as mid-level jet noses in. Any convection
will quickly move off to the northeast and more widespread rainfall
will begin to overspread the region from southwest to northeast
Tuesday morning. A surface front, associated with the incoming
system, will slowly push eastwards tomorrow...becoming nearly
stationary by Tuesday afternoon. Several rounds of moderate to heavy
rainfall will develop along this front as a deep layer of moisture
is pulled over the region. A surface low associated with the
remnants of Polo will lift across New Mexico/Panhandles towards SE
Colorado/SW Kansas late Tuesday into Wednesday. In response, the
front will begin to to lift and out of the area. Depending on which
model verifies and where the surface low actually tracks, will
impact rainfall amounts for Wednesday and Thursday. Right now, there
is a good probability (60-80%) that most of the forecast area will
see widespread rainfall amounts of 1-3 inches through Thursday, with
some locally higher amounts possible. As such, in localized flooding
will be a concern this week, especially for areas in east-central
Kansas where heavier rainfall over the past week has led to more
saturated soils.

&&

.LONG TERM /WEDNESDAY THROUGH SUNDAY/...
Issued at 310 PM MDT Sun Sep 27 2026

A variety of weather is in store for the Tri-State area through
Sunday. The long term period will start off wet and windy until
sunny skies return Friday morning. Temperatures will be consistent
with high temperatures forecast in the 60s to 70s Wednesday through
Sunday.

Wednesday morning, our region is forecast to remain in a mostly
southwest upper-level flow with a jet streak overhead. This jet
streak is expected to remain over the region through Thursday
creating windy afternoons. Gusts from 30 to 45 mph are possible
for the area, with our Colorado counties being on the higher
end. There is also a cut off low in southwest CONUS that is
forecast to traverse east that will eventually take us out of
our rainy pattern. Models are showing anywhere from 1-3 inches
of rain Wednesday through Thursday evening with a band of
localized heavier rainfall setting up somewhere in the county
warning area (CWA). The speed and track of the upper-level cut
off low and where a surface low sets up in western Kansas will
ultimately determine precipitation amounts. Severe weather is
not anticipated due to lack of instabilty in the environment.
Lapse rates are shallow, shear is weak and CAPE is lacking.
Wednesday evening would be our best chance for weak
thunderstorms based on GFS ensembles showing <10% chance of CAPE
values greater than 500 J/kg. Low confidence (<10%) that any
weak thunderstorms are able to form. Models are in a bit of
disagreement on how quickly this low will move on, but rainy
conditions for the CWA are forecast to end sometime Thursday
evening.

Friday, sunny skies return to the CWA as we enter a weak
northwesterly to zonal upper-level pattern. Precipitation is
not expected as Probability of Precipitation (PoPs) are less
than 5% for the Tri- State area. A weak jet streak may set up
over the area Friday and remain through the weekend. This could
cause some windy conditions for our Colorado counties with
afternoon gusts around 30 mph possible. Fire weather is not a
concern at this time due to steady precipitation expected
through the week and relative humidity (RH) values generally
forecast over 30%.

&&

.AVIATION /06Z TAFS THROUGH 06Z TUESDAY/...
Issued at 1127 PM MDT Sun Sep 27 2026

GLD: Southeast winds of 10 to 15 kts will persist through the
period. Gusts of 20 to 28 kts will become more likely after
sunrise as daytime mixing sets in. Given southeasterly flow,
there is a possibility that visibility could drop to MVFR
overnight with IFR/MVFR ceilings developing, but will quickly
return to VFR through mid-morning. Mid and upper-level cloud
cover will be on the increase through the afternoon and into the
evening.

MCK: Low VFR or MVFR ceilings will develop by 07-09Z with the
potential for IFR ceilings between 09-11Z. Low stratus is more
favorable tonight versus dense fog, but there could be periods
where visibility drops below IFR near sunrise. Any fog and low
stratus will start to mix out by mid-morning with southeasterly
winds increasing to 10 to 15 kts, with gusts of 15 to 25 kts,

&&

.GLD WATCHES/WARNINGS/ADVISORIES...
KS...None.
CO...None.
NE...None.

&&

$$

SHORT TERM...Pietrycha
LONG TERM...Rhoades
AVIATION...Pietrycha