National Weather Service Forecast Discussion

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564
FXUS65 KBOU 091725
AFDBOU

Area Forecast Discussion
National Weather Service Denver/Boulder CO
1125 AM MDT Fri Oct 9 2026

.KEY MESSAGES...

- Unseasonably warm through at least Sunday.

- Mainly dry weather continues, with only isolated to scattered
  showers (15-30% coverage) and a couple weak storms over the
  mountains through Saturday. Any precipitation would be light.

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

- Pattern change next week, with cooler temperatures finally
  arriving by Tuesday. Main precipitation chances hold off until
  the middle of next week, but even then much uncertainty.

&&

.DISCUSSION /Through Thursday/...
Issued at 1053 PM MDT Thu Oct 8 2026

The upper level ridge that dominated our weather for the last
several days will shift eastward Friday, with a light southwest
flow aloft developing across the area. That will support another
very warm day, with record or near record temperatures once again.
The forecast maximum at Denver is 86F, which would be just a
degree shy of the record (87F set in 1910). There will be some
lingering mid level moisture, just enough for isolated high based
showers over the mountains, capable of producing gusty outflow
winds to 30-40 mph.

Saturday will see stronger southwest flow aloft, resulting in
another unseasonably warm day and an increase in winds for the
late morning and afternoon hours. With that comes elevated to
locally critical fire weather conditions, but humidity increases
across the mountains along with a slight drop in temperatures.
The overlap of lowest humidity and breezy winds gusting to near 25
mph will be over Washington and Lincoln Counties, but even there
conditions are marginal for potential Red Flag. With slight
cooling aloft, we should see a couple degrees of cooling except
the far northeast plains where downslope will support highs in the
upper 80s/near 90 yet.

For Sunday to Monday, not a lot changes (or has changed in model
solutions) as the upper trough dives down the West Coast. Again,
almost all influence of this trough and the remnants of Hurricane
Rachel will stay well to our west. There is almost no chance of
rain for the plains during this time, with only a chance of
passing showers for the northern mountains. All the significant
precipitation will stay far to our west in the Desert Southwest
and Great Basin. Temperatures will almost certainly stay well
above normal with highs in the lower 80s for the lower elevations,
potentially cooling a bit Monday, still depending on a backdoor
cold front.

Our main precipitation chances will have to wait until the upper
level low ejects out of the southwest U.S. and across the Rockies.
There remains a great deal of uncertainty regarding the eventual
track of this low, and thus who gets precipitation and when those
higher chances would occur. The latest trends seem to be favoring
locations north and east of our forecast area Tuesday night -
Thursday. However, there are still several ensemble members that
show a round of modest precipitation (30-40% chance of 0.5"
liquid with the odds favoring locations near the Wyoming border).
Ensembles have also trended weaker with the trailing shortwave
into Thursday or Friday, which means a decreasing chance (already
small) of any snowflakes into lower elevations. We do think the
current forecast track of the low would at least bring a few
inches of snow to some of our northern mountains.

&&

.AVIATION /18Z TAFS through 18Z Saturday/...
Issued at 1120 AM MDT Fri Oct 9 2026

VFR conditions expected through the TAF period. A weak shear zone
is starting to become evident along the foothills to the west of
KBJC. Winds are rather uncertain for this afternoon due to a
potential cyclone and/or shear zone. The forecast calls for mainly
a southerly component at KDEN and KAPA with winds about 10-15 kts
this afternoon. A shear zone looks to continue to develop
somewhere over the Denver metro later this afternoon. Therefore,
we expect mainly a northerly component at KBJC. The shear zone
could introduce northerly winds into KDEN during the late
afternoon and/or early evening if it were to move to the east.
Winds could also briefly gust to 15-20 kts at times this
afternoon.

Tonight, winds turn to an elevated drainage of 8 to 12 kts. Winds
should start to turn clockwise towards the west by early Saturday
afternoon. Only a few to sct mid- and high-level clouds are
possible through the period.

&&

.BOU WATCHES/WARNINGS/ADVISORIES...
None.

&&

$$

DISCUSSION...20
AVIATION...MV

NWS BOU Office Area Forecast Discussion