Pritchett, Colorado Weather Forecast Discussion

687
FXUS65 KPUB 070743
AFDPUB
Area Forecast Discussion
National Weather Service Pueblo CO
Issued by National Weather Service Grand Junction CO
143 AM MDT Sun Sep 7 2025
.KEY MESSAGES...
-  A couple strong to severe storms will be possible on our
   eastern plains today.
-  Daily showers and thunderstorms expected over the mountains
   and the eastern plains throughout the forecast period with
   the main idea that weak storms will develop over the west and
   intensify closer to the Kansas border each day.
&&
.SHORT TERM /THROUGH MONDAY/...
Issued at 122 AM MDT Sun Sep 7 2025
Today, mid level heights/temps continue to build/warm as upper ridge
amplifies over the srn Rockies, with drier air spreading over the
higher terrain through the day. As a result, expect just isolated to
scattered mountain convection this afternoon, with mainly gusty/high
based storms into early evening.  On the plains, weak surface trough
develops and moves east of I-25, with model solutions of boundary
position anywhere from near La Junta to wrn KS by early evening.
Deep moisture/instability (CAPE 1000-2000 J/KG) will pool east of
the boundary by late afternoon, while bulk shear climbs into the
30-40 kt range. Upward forcing should be provided by a couple of
weak disturbances cresting the upper ridge and diving into the
central plains late this afternoon and evening, and many CAMs now
develop strong storms over the plains, with activity lingering well
into the evening near the KS border. SPC has a marginal risk for
the plains east of a Limon/La Junta/Kim line, which looks reasonable,
and will add some pops to most of the plains for today/this evening.
Max temps continue their upward climb with much of the plains deep
into the 80s, and 70s/lower 80s farther west at most other low/mid
elevation locations.
Storms move into KS overnight with most activity ending by midnight,
though latest HRRR has a few cells lingering on the plains south of
the Arkansas R. until 2-3 am. On Mon, ridge continues to build with
the return of 90 degf readings on the plains from Pueblo eastward,
while interior valleys see a mix of 70s/80s, mostly 70s mountains
(60s higher peaks). Models suggest lee surface trough will be near the
KS border, with deepest surface moisture and instability staying just
east of the area through the day. Still enough mid-level moisture for
the usual crop of high based mountain convection/virga, with some
windy sprinkles into the I-25 corridor and eastern plains, but not
expecting much meaningful rainfall.
&&
.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
Issued at 128 AM MDT Sun Sep 7 2025
Monday Night and Tuesday:
The upper level ridge builds overhead with height rises being
resolved on the 500hPa charts, but embedded in the flow are weak
waves, meaning that isolated to scattered showers and
thunderstorms are expected over the mountains, mountain valleys,
and over the southern I-25 corridor. Less than 500 J/kg of CAPE
are expected over the western  of the region, with some higher
instability values located over the far eastern plains.
However, the wave will primarily spark thunderstorms over the
western  of the CWA and not quite reach the better atmosphere
for stronger storms. So overall, the main risk for storms will
be lightning and gusty outflow winds during the evening on
Monday. Tuesday will have a little more to work with as a closed
low begins to propagate southeast increasing the moisture
transportation from the Pacific and a stronger wave aloft passes
over Colorado. There are two main outcomes that are being
resolved  one being scattered to likely convection developing
over the mountains, mountain valleys and adjacent plains then
increasing in strength as it hits more unstable air over the far
eastern plains and the other being just a singular strong to
severe thunderstorm that develops north of our CWA and
intensifies once it hits the unstable air. So overall, the main
thunderstorm risk is 1-1.5 hail and 60-70 MPH wind gusts later
in the evening over the far eastern plains on Tuesday night.
Wednesday through Saturday:
As the low-pressure center continues its journey SE, the center
will stall over the Oregon, California, and Nevada state
boundary area. This is actually a bit of shift from last nights
forecast package which had the closed low propagating even
further to the SE towards to four corners region. With tonight
information the convection seems to be limited as the main plume
of moisture is directed further to the west than previously
forecast, so therefore itll look fairly similar to Tuesday
forecast of weak storms forming over the western half of the
then reaching the far eastern plains where they would intensify
with perhaps an isolated severe thunderstorm, max with 1 hail
and 60 MPH, but more likely just gusty winds and small hail
stones. This forecast remains consistent with the Thursday
forecast, as well. On Friday, the closed low that has been
stalled over the western US starts to push to the northeast
getting caught up in the upper level flow. As it propagates to
the northeast the main trough axis passes overhead which is
expected to be the strongest wave of the week sparking
widespread convection on both Friday and Saturday. Early
guidance states that the MUCAPE values are around 500-800 J/kg,
so that indicates non-severe thunderstorms - the shear values
are relatively low too. At this pint in time critical fire
weather conditions are not expected, however minimum RH values
are around 20% for the region, which I assume the trends will
lower that a little bit more. No big cause of concern at this
point in time. High temperatures will remain fairly steady state
throughout the long term forecast period with highs in the
upper 70s to upper 80s over the plains and the 60s to 70s over
the mountain valleys.
&&
.AVIATION /06Z TAFS THROUGH 06Z MONDAY/...
Issued at 1141 PM MDT Sat Sep 6 2025
VFR conditions anticipated across much of the forecast area over
the next 24 hours, including the three main TAF sites of KCOS,
KPUB and KALS. Showers and thunderstorms once again expected by
midday over the higher terrain, spilling across the I-25 Corridor
through the late afternoon. KCOS has the best chance of seeing
some thunder, so included PROB30 wording for -TSRA and variable
gusts to 25 kt from 23z-03z.
&&
.FIRE WEATHER...
Issued at 128 AM MDT Sun Sep 7 2025
Critical fire weather conditions are not expected for the next
seven days, though winds will increase late week into the weekend,
bringing the potential for some locally enhanced conditions.
There will be enough moisture around the region to keep isolated
to scattered afternoon showers and thunderstorms in the forecast
from today through Thursday, though wetting rainfall will be
spotty at best. Better moisture returns late week and next weekend,
bringing back increased chances for precipitation to the area.
Temperatures will be generally above seasonal averages the next
several days, potentially cooling slightly next weekend.
Afternoon smoke dispersion will be fair to good across the district
today, climbing to good or better at most locations on Monday as
mixing heights continue to rise.
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
SHORT TERM...PETERSEN
LONG TERM...SKELLY
AVIATION...MOORE
FIRE WEATHER...PETERSEN

NWS PUB Office Area Forecast Discussion