National Weather Service Forecast Discussion

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462
FXUS65 KBOU 081149
AFDBOU

Area Forecast Discussion
National Weather Service Denver/Boulder CO
549 AM MDT Thu Oct 8 2026

.KEY MESSAGES...

- Unseasonably warm through Saturday and quite likely (>70%
  chance) through Sunday. Cooling keeps getting delayed.

- Mainly dry weather continues, with only isolated to scattered
  showers (15-30% coverage) and a lone storm for the mountains and
  higher terrain. Any precipitation would be light.

- Elevated fire weather conditions as southwest breezes increase,
  especially by Saturday.

- Pattern change late this weekend and early next week, but main
  impacts, at least in terms of precipitation chances, would hold
  off until the middle of the week.

&&

.DISCUSSION /Through Wednesday/...
Issued at 1134 PM MDT Wed Oct 7 2026

It`s the same old story with a continuation of summerlike daytime
warmth Thursday, Friday, and Saturday. This is supported by the
current upper level ridge holding across the state through
Thursday, and then warm southwest flow as the ridge shifts to the
east. It appears there will still be enough moisture around for
isolated to low end scattered convection, mainly in the mountains.
High temperatures Thursday will be a good 4-5 degrees warmer as
we`ll start to see lee troughing. That means highs pushing back
into the mid 80s across the plains and I-25 Corridor. That puts us
close to record warmth once again (Denver`s record is 85F set in
2020 and and 1910). Friday will likely be the warmest day, adding
on another degree or two for highs with mid to upper 80s in the
lower elevations. Denver`s record for Friday bumps up a couple
degrees as well (87F set in 1910), so again we`ll be pushing very
close to that. Saturday is expected to cool just a couple degrees
given slight cooling aloft, but that`s still nearly 15 degrees
above normal. Increasing breezes on Friday and especially Saturday
will support elevated fire weather conditions, with near critical
conditions over Lincoln and Washington Counties.

While the weather pattern changes significantly by Sunday, the
impacts on eastern Colorado will likely be minimized. Southerly
flow aloft will intensify as a deep upper level trough slides
southward down the West Coast. That high amplitude trough will
pick up the remnants of Hurricane Rachel, spreading another round
of widespread and locally heavy rainfall into the Desert Southwest
and Great Basin. Portions of western Colorado will get in on some
of this rain (with greater uncertainty though given the digging
and depth of the trough and potential for weak ridging), while
most of our forecast area is now expected to see little if any
precipitation from this first wave. We`ll likely have to rely on
the trough to start ejecting eastward (Tuesday night - Wednesday
night) and picking up the remnants of soon to be Hurricane Simon
in the Eastern Tropical Pacific. However, even then the bulk of
precipitation will be wrung out over the mountains of New Mexico
and southern Colorado before any leftover showers would even have
a chance of reaching our lower elevations. Ensembles support that
as well with less than a 10% chance of 1" of rain over most of the
plains and I-25 Corridor. The northern mountains have slightly
better odds (20-30% chance of 1") given less blocking.

At this point, it appears our best chance of precipitation
(mountain snow and a low 20% chance of the first snow into lower
elevations) would surround a trailing and colder trough
mostly beyond this forecast period. However, there is considerable
uncertainty as models are all over the place once we move past
Wednesday. That`s not surprising given the complexity of all the
tropical systems being consumed by mid latitude cyclones.

Regarding temperatures, warmth will likely continue into Sunday
with near 80 degree readings still possible along the Front Range.
Then models diverge considerable Monday with some showing a
backdoor front and others keeping warm southerly flow in place.
Thus, for Monday and beyond we`ll generally have a middle of the
road forecast. While deterministic highs are mostly in the 70s
Monday, beware of large potential outcome range all the way from
the upper 40s to the upper 80s on the extreme ends, while 25th-75th
percentiles still have nearly a 20 degree range from ~60-80F. A
gradual cooldown is expected Tuesday - Thursday as we`ll have
higher odds of a front and cooling aloft with the trough, so
finally some autumn-like temperatures returning to the forecast.

&&

.AVIATION /12Z TAFS through 12Z Friday/...
Issued at 547 AM MDT Thu Oct 8 2026

Another tranquil day ahead with winds generally remaining light
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NWS BOU Office Area Forecast Discussion