924
FXUS63 KGLD 280601
AFDGLD

Area Forecast Discussion
National Weather Service Goodland KS
1201 AM MDT Mon Sep 28 2026

.KEY MESSAGES...

- Breezy and mostly dry conditions continue into tomorrow
  afternoon, with gusts as high as 40-45 mph possible for
  portions of the eastern Colorado Counties tomorrow morning
  into the early afternoon hours.

- Chances of rain become widespread late tomorrow night,
  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 Risk (level 2/4) of isolated flash flooding is possible
  across the region on Tuesday and Tuesday night.

&&

.SHORT TERM /THROUGH TUESDAY NIGHT/...
Issued at 326 PM MDT Sun Sep 27 2026

Aside from a low (10-15%) chance of a few spotty and brief showers
tonight into tomorrow morning, a ridge axis passing over aloft
maintains dry conditions. Meanwhile, a pressure gradient begins
to tighten across the region, most pronounced over the western
CWA, as a series of upstream mid-level shortwave troughs behind
the ridge move northeastward and lower heights across the western
US and Rockies in advance of a digging and developing cut-off
mid/upper-level low and trough arriving over California. This
should transition southeasterly winds to southerly and increase
along/west Highway 27 (eastern Colorado counties) throughout
tonight, possibly peaking as high as 20-30 mph, with gusts of
40-45 mph, by late tomorrow morning. Lighter upslope (southeasterly)
winds further east are expected to result in patchy to areas of
fog late tonight into tomorrow morning, with localized dense
fog possible, where visibility could drop to half a mile or
less (15-30% probability) before scattering out as the morning
progresses.

By the later afternoon and early evening hours tomorrow, heights
begin to lower as the initial shortwave arrives over the region,
thus loosening the pressure gradient and weakening southerly
winds throughout tomorrow night. Meanwhile, models are beginning
to converge on an initial push of scattered to numerous light
to moderate stratiform rain arriving sometime tomorrow evening,
building chances of rain from west-to-east and becoming a
widespread medium to likely (50-80%) chance by Tuesday morning.
As the shortwave passes to the northeast, deeper moisture,
streaming off and northeastward from what is currently Hurricane
Polo nearing the Baja Peninsula, begins to pool ahead of and
along a lee surface low pressure system and attendant cold
front, expected to gradually shift winds to northerly from west-
to-east on Tuesday as the low moves across the CWA while also
increasing chances of rain further to a medium to likely (60-90%
+) chance Tuesday afternoon into Tuesday night. Cloud cover and
a shift in winds to northerly is likely to drop highs in the
mid/upper 70s tomorrow to the upper 60s and low 70s on Tuesday
while overnight lows in the 50s and 60s persist.

Additionally, as bulk shear and instability begin to increase
slightly throughout the later half of Tuesday, in association with
the secondary shortwave aloft, heavier showers and non-severe
thunderstorms along/ahead of the cold front become more likely,
especially along/south I-70 and along along/east of US-83,
where the higher chances of rain reside; by Wednesday morning,
we expect for total rainfall amounts across this area to
generally range around 1.5 to near 2.0 inches, though NBM still
suggests a 40-70% probability of totals exceeding 2.0 inches,
perhaps even more in areas where heavy rain and thunderstorms
develop and/or train. Areas further north and west should see
lesser amounts, around 0.5 to 1.5 inches, though more persistent
heavy rain could result in higher amounts as well, with the NBM
also indicating a 20-50% probability of amounts greater than 1.5
inches by Wednesday morning. Due to the well-above normal
moisture content (1.3-1.8 in. PWAT by Tuesday evening), all of
the region is included within a Slight Risk (level 2/4) of
isolated flash flooding from excessive and heavy rainfall
Tuesday through Tuesday night.

&&

.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...Irish
LONG TERM...Rhoades
AVIATION...Pietrycha