Cope, Colorado Weather Forecast Discussion

680
FXUS65 KBOU 262034
AFDBOU
Area Forecast Discussion
National Weather Service Denver/Boulder CO
234 PM MDT Fri Sep 26 2025
.KEY MESSAGES...
- Warm and dry through Saturday.
- The next disturbances will be weak, bringing a chance of light
  precipitation Sunday to Wednesday, mainly for the mountains.
- Temperatures will remain above normal most days.
&&
.DISCUSSION /Through Friday/...
Issued at 233 PM MDT Fri Sep 26 2025
The upper level ridge axis is expected to amplify across the
forecast area Saturday, limiting any moisture advection from the
Desert Southwest. As a result, we expect another mostly sunny day,
although temperatures will be a few degrees cooler thanks to a
cold front that will be moving across the northeast plains this
evening. However, the forecast highs in the mid to upper 70s over
most of the plains and I-25 Corridor will still be a degree or two
above normal.
On Sunday, models are still consistent shifting the ridge axis to
our east, and shearing the upper low in the deep Desert Southwest.
This will allow moisture advection to begin, although with southerly
flow the best moisture advection and main shower/storm chances
Sunday afternoon and evening will remain over the mountains. It
appears that most lower elevation areas will stay dry, with only
an isolated high based weak storm/sprinkle given high cloud bases
and limited instability. That should change a little by Monday as
models do show the shearing trough pushing northeast across
Colorado. As a result, we expect a little more forcing, higher
moisture, and a better chance of scattered showers/few storms
spreading onto the plains.
By Tuesday, we`ll likely be in between disturbances but more
uncertainty enters the picture since there are some timing
differences between models/ensemble members. The best consensus is
for a weak shortwave passage late Tuesday night or Wednesday with
another chance of showers and a few storms. However, any
precipitation is expected to be light with limited moisture
availability and minimal instability.
We then see another totally dry day or two Thursday into Friday,
before the next weather disturbance arrives in west/southwest flow
aloft. It should be noted there`s quite a bit of uncertainty
regarding timing here.
Temperatures will average a few degrees above normal through this
entire forecast period; highs mostly in the mid 70s to lower 80s
degree range in lower elevations, mid 60s to lower 70s foothills
and high valleys, and 50s to lower 60s mountains.
&&
.AVIATION /18Z TAFS through 18Z Saturday/...
Issued at 1141 AM MDT Fri Sep 26 2025
VFR to prevail through the TAF period with only SCT-BKN and mainly
thin clouds above 16,000 ft MSL. Winds are in the process of
turning to light northeast 20Z-01Z. Some uncertainty enters the
picture thereafter as a cold front is expected to push across the
area which would mean a disruption of normal diurnal wind patterns
tonight and a more northerly push. We think that`s most likely to
occur 03Z-05Z given the momentum this front has through northeast
Wyoming at the present time. Also interesting to note a couple
solutions never have the E/SE winds developing 01Z-03Z this
evening and keep a light northerly component in place.
Nonetheless, after the frontal surge this evening we don`t see a
strong signal in low level winds (ranging anywhere from NW-NE-SE)
so we`ve gone with VRB 10Z-15Z. By 15Z, an anticyclonic flow
pattern should establish itself over northeast Colorado, leading
to a gradual increase in east/southeast winds 15Z-24Z Friday.
Gusts 20-25 kts possible after 22Z.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
DISCUSSION...Barjenbruch
AVIATION...Barjenbruch

NWS BOU Office Area Forecast Discussion