303
FXUS65 KBOU 201114
AFDBOU

Area Forecast Discussion
National Weather Service Denver/Boulder CO
514 AM MDT Tue Oct 20 2026

.KEY MESSAGES...

- Mild temperatures through Friday. Mostly dry through early
  Wednesday.

- Isolated light rain/snow showers possible over the mountains
  Tuesday afternoon.

- A more organized system late Wednesday through early Friday,
  with rain showers becoming more numerous over the mountains.

- Seasonable temperatures for the weekend into next week.

&&

.DISCUSSION /Through Monday/...
Issued at 1148 PM MDT Mon Oct 19 2026

There have been only minimal changes to the forecast over the last
24 hours. The Denver metro and the plains will see high
temperatures in the 70s through the week with high temperatures
even pushing 80 on the eastern plains for Wednesday and Thursday.
Some record warm minimums are possible for Denver towards the end
of the week as cloud cover increases.

Radar over the last several hours has shown some isolated to
scattered rain/snow showers for the mountains, but there is almost
no precipitation left at this hour. An upper-level ridge builds into
eastern Colorado on Tuesday and Wednesday with our area on the
periphery of it and some drier air filtering in. Wednesday and
Friday should be the warmest days of the week ahead. Rain chances
start to decrease, even compared to the relatively low chances we
had on Monday. Tuesday only brings the chance for isolated
rain/snow showers for the mountains. The coverage drops to near
zero on Wednesday until late in the afternoon. Almost no
accumulation is expected through at least 18z Wednesday. By
Wednesday afternoon, more widespread showers should start to
approach our southwestern counties.

The overall synoptic pattern forecast through Friday generally
remains the same as noted in previous discussions. An upper-level
low over the Pacific Ocean should approach California on Wednesday,
move inland, and be centered over Utah by Friday morning. Southwest
flow aloft looks to continue through the week for our area with
moisture starting to increase on Wednesday. Some moisture
associated with what is now Tropical Storm Trudy gets pulled into
the flow aloft and funneled into southwest Colorado for late
Wednesday through Friday. The vast majority of the precipitation for
our area should stay in the high country, but there is a a low
chance a couple of showers could move onto the plains late Thursday.
As such, we now are forecasting little to no rainfall for the Denver
metro and the plains. Ensemble data remains in good agreement that
the highest rainfall amounts for our area will be in the southern
high country (Park and Summit counties) where 0.25" to 0.50" looks
reasonable with perhaps some localized slightly higher amounts. The
rest of the high country likely sees 0.25" or less. The system has
trended warmer, so only light snow accumulations at most are
possible mainly above 12,000 ft.

There is some more agreement for this package on the evolution of
the trough for Friday and beyond. It now looks like the trough could
split into two with part of it forming into a low near the Four
Corners with the other part continuing to move off to the north and
east late Friday through the weekend. A cold front should move
through the forecast area early Saturday dropping high temperatures
back to near-average or even below-average for Saturday through the
beginning of next week. It will start to feel more like fall once
again! Precipitation chances look to continue into the weekend,
mainly on Saturday, with the highest chances once again for the high
country and perhaps the Palmer Divide given an upslope component
there behind the cold front.

&&

.AVIATION /12Z TAFS through 12Z Wednesday/...
Issued at 511 AM MDT Tue Oct 20 2026

Winds have already become light and variable early this morning.
Expect that continue thru late this morning before winds switch
to a northerly direction by 19z. In the 23z-00z period expect
winds will become more easterly and then southeast by 02z-03z
this evening.  Winds overnight will be mainly drainage.  VFR
conditions will continue thru the period.

&&

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

&&

$$

DISCUSSION...MV
AVIATION...RPK

NWS BOU Office Area Forecast Discussion