Dupont, Colorado Weather Forecast Discussion

371
FXUS65 KBOU 010033
AFDBOU
Area Forecast Discussion
National Weather Service Denver/Boulder CO
633 PM MDT Tue Sep 30 2025
.KEY MESSAGES...
- Isolated, high-based showers late Tuesday afternoon and evening.
- Dry with warmer than normal conditions Wednesday through Friday.
- Cooler temperatures along with unsettled weather likely
  returning for the weekend.
&&
.DISCUSSION /Through Tuesday/...
Issued at 105 PM MDT Tue Sep 30 2025
A narrow moisture layer aloft has allowed for plenty of shallow
stratocumulus to develop over the high country, but stable upper
levels have thus far ensured echo-free radar scans as of ~1pm.
Forecast soundings suggest that this stable layer near 500mb
should erode by late afternoon across most of the region, leading
to marginally unstable conditions and a better shot at expansion of
isolated to scattered showers into the urban corridor and plains,
along with a potential thunderstorm or two through this evening.
Cloud bases look to be quite high, with the saturation level
closer to 600mb, so precipitation shouldn`t be as heavy or
widespread relative to previous days. With healthy low-level lapse
rates exceeding 9 C/Km, gusty outflow winds to around 40 mph
would be the main threats from any late day and high-based
convection. For tonight, a lifting jet maxima will provide a boost
to winds in the foothills and mountains, and the subsident flow
will make for a mild night area-wide.
High pressure to our south and east will gain increased prominence
Wednesday through Friday, keeping northeast Colorado dry and
making for progressively warmer conditions. Temperatures look to
peak Friday, particularly for the lower elevations, where highs
will climb to the mid to locally upper 80`s - approximately 15
degrees above average. Winds look to pick up slightly on Friday
ahead of an approaching trough, and would favor areas of elevated
fire weather conditions in our southern plains where humidity will
be lowest, although recent precipitation will serve to buffer the
threat.
The next feature to watch will be a developing closed low over
California and Nevada around Friday, which ensemble guidance
indicates will accelerate northeastward as we enter the weekend
and bring us our next shot at meaningful precipitation. The latest
guidance has trended quicker with the progression of this low,
rapidly merging the dissipating shortwave into the broader
longwave flow by Sunday, which would limit precipitation potential
to a degree. Regardless, it still appears we should see a
transition to more unsettled weather for the weekend and notably
cooler temperatures, with higher confidence in precipitation
potential for the high country and northern counties given the
more northerly track depicted by current ensemble mean solutions.
There is little model consistency thereafter, however it looks
likely that a general troughing pattern will be favored for the
western half of the CONUS into early/mid next week, thereby
providing additional opportunities for active and cooler weather.
&&
.AVIATION /00Z TAFS through 00Z Thursday/...
Issued at 630 PM MDT Tue Sep 30 2025
A weak cluster of showers and storms is currently over the
southern foothills. These will weaken to showers as they move
across the Denver metro but they could produce gusty winds up to
30 knots. A PROB30 for wind gusts was added to the KAPA TAF due to
the proximity of the showers and storms. The best chance for wind
gusts is between 01-03Z.
Otherwise, there will be VFR conditions with light winds. Drainage
winds are expected later tonight with light winds tomorrow
morning. Easterly or northeasterly winds will develop in the
afternoon with drainage again tomorrow night.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
DISCUSSION...Rodriguez
AVIATION...Danielson

NWS BOU Office Area Forecast Discussion