823
FXUS65 KBOU 092139
AFDBOU

Area Forecast Discussion
National Weather Service Denver/Boulder CO
339 PM MDT Thu Oct 9 2025

.KEY MESSAGES...

- Above normal temperatures continue through Sunday.

- Scattered showers and isolated thunderstorms return Friday and
  Saturday, mainly across the higher terrain.

- Near normal temperatures with chances for showers Sunday into
  early next week, though confidence in the weather pattern is
  low.

&&

.DISCUSSION /Through Thursday/...
Issued at 330 PM MDT Thu Oct 9 2025

Current satellite and radar shows clouds building over the higher
terrain with light rain showers, as moisture increases ahead of
an approaching system. Isolated showers will continue through the
evening, mainly for the higher terrain. However, can`t rule out
light showers spilling onto adjacent plains. Have increased PoPs
this evening.

Broad southwest flow aloft will dominate the region on Friday and
Saturday as an upper level low in the Pacific Northwest pushes the
500-mb ridge eastward. Moisture from the remnants of Hurricane
Priscilla will be advected into Colorado, with PWAT values above
the 90th percentile and 200-300% of normal. The bulk of the
precipitation will stay southwest of our CWA, as the mountains to
our southwest will block most of the moisture advection. However,
scattered showers are expected throughout both days across the
higher terrain, with a few rumbles of thunder in the afternoon.
700-mb temps will stay above 0 dg C, supporting snow levels above
10K ft.

For the plains, the best chance of precipitation will be late
Friday afternoon/evening and Saturday morning. Increasing
southwest flow aloft from an embedded shortwave will provide
enough forcing for light isolated to scattered showers. In terms
of temperatures, expect daily highs to be 5-8 degrees above
normal this weekend. A few short range models indicate Friday`s
high temperatures to be in the high 70s. However, with the
expected increase in cloud cover, have kept temperatures in the
low to mid 70s.

By Sunday, the upper level low will weaken and move eastward as
flow aloft turns more westerly. With cross-barrier flow, gusty
winds up to 50 mph and orographic rain/snow are possible along
the higher terrain. For the plains, a cold front will traverse the
area in the afternoon, bringing cooler temperatures behind it for
Monday.

For the rest of next week, broad southwest flow aloft will return
as another upper level low develops in the Pacific Northwest.
There is still a wide variability in ensemble solutions in terms
of track and intensity. However, guidance has been trending
towards the low staying west of our area, due to a ridge building
over the southern United States. If this trend continues, above
normal temperatures will be expected next week.


&&

.AVIATION /18Z TAFS through 18Z Friday/...
Issued at 1133 AM MDT Thu Oct 9 2025

VFR conditions expected through the TAF period. The temperature
inversion has been slow to break, so SW winds have held on for the
past couple of hours. Expect a transition to ESE in the early
afternoon before returning back to light drainage winds overnight.

For tomorrow morning, there is some model variability on whether
winds will stay SW or turn SE. Most likely, stronger SE winds
(10-15 kts.) will prevail. An upper level system will arrive on
Friday, with the possibility of scattered rain showers to all
terminals in the afternoon. Have introduced a PROB30 to the TAF
for this reason. In addition, ceilings should drop down to 6,000
ft. by 15Z, although could be earlier depending on the timing of
the system.

&&

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

&&

$$

DISCUSSION...MAI
AVIATION...MAI