986
FXUS65 KBOU 291124
AFDBOU

Area Forecast Discussion
National Weather Service Denver/Boulder CO
524 AM MDT Thu Oct 29 2026

.KEY MESSAGES...

- Mild and mostly dry through the work week.

- Unsettled weather returns late this weekend and early next week.
  Mountain snow is likely (>70% chance) above 8500ft during this
  time. High uncertainty remains for the foothills and plains.

&&

.DISCUSSION /Through Wednesday/...
Issued at 1032 PM MDT Wed Oct 28 2026

SW flow aloft will be over the area Thu thru Fri.  A weak
disturbance will be embedded in the flow on Fri. However, it appears
most of the moisture with this feature will stay mainly to the
east, with only a slight chc of showers over he far nern plains.
Temperatures both days will stay in the 60`s over the plains.

By Sat, little change is expected as SW flow aloft remains over the
area. There appears to be a weak disturbance embedded in the flow
which may bring a chc of showers to portions of the higher
terrain. Temperatures will remain in the 60`s over nern CO.

Looking ahead to Sun and Sun night, there continues to be a lot of
uncertainty as to how an upper level trough over the Pacific NW
evolves. The ECMWF has this feature moving southeast with a closed
low developing over the Great Basin by Sun night. Meanwhile, the
GFS has the system moving more east southeast with a closed low
over swrn WY by Sun night. Ahead of this feature, both models do
have an influx of subtropical moisture with an increasing chc of
showers over the higher terrain late Sun aftn thru Sun night. Over
the plains, a sfc lee trough will extend from ern WY into ern CO
with southerly low level flow. Most of the plains will be dry thru
Sun aftn, but shower activity may gradually increase Sun night.

For early next week, the ECMWF has an upper level low near the 4
corners area by 12z Mon which moves east southeast across nrn New
Mexico thru late Mon aftn.  Meanwhile, the GFS has the upper level
low over swrn WY moving east southeast across central CO into sern
CO by late Mon aftn. As a result, these two differing solutions
lead to varying amounts of precipitation over the area. The ECMWF
solution would keep the heavier precipitation focused over srn CO
while the GFS solution would focus further north over nern CO.

Furthermore, the fcst continues complicated for Mon night into
Tue as the ECMWF has the upper level low moving southeast into wrn
Texas while the GFS has the upper level low over central Kansas.
The ECMWF solution would have precipitation ending over most of
the area by 12z Tue while the GFS solution would have lingering
precipitation thru Tue aftn over portions of the plains. In
addition, both models do have a shot of cooler air moving in Mon
thru Mon night which could change some of the rain to snow late
Mon night into Tues morning at lower elevations. However, ensemble
data from both models only show very light accumulations below
6000 ft if the rain does change to snow. To complicate things even
further, the Canadian solution keeps the track of the main upper
level low well to the north of the area from late Sun night thru
Tue morning. As a result, it has very little precipitation across
the area due to its northern track. Thus, there remains a
tremendous amount of uncertainty as to how things will develop Sun
night thru Tue.

&&

.AVIATION /12Z TAFS through 12Z Friday/...
Issued at 516 AM MDT Thu Oct 29 2026

VFR conditions will prevail for all terminals through the TAF
period. Light SW drainage flow is currently in place at KDEN/KAPA
and will persist until slightly after sunrise, before becoming
increasingly light and VRB (< 6 kts) after ~15-16Z. Come early
afternoon (~19-20Z), east flow looks to become established at the
above terminals. It should initially be rather light, but a 2-3 hr
window of modestly stronger speeds 10-12 kts could play out,
mainly 21-00Z. It`s possible KDEN sees a slight nudge towards an
ENE wind near or shortly ater 00Z (< 10 kts), but this will
quickly swing clockwise back towards typical southerly drainage
flow patterns mid-evening, with lighter speeds.

&&

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

&&

$$

DISCUSSION...RPK
AVIATION...BRQ

NWS BOU Office Area Forecast Discussion