286
FXUS65 KBOU 112348
AFDBOU

Area Forecast Discussion
National Weather Service Denver/Boulder CO
548 PM MDT Sun Oct 11 2026

.KEY MESSAGES...

- Unseasonably warm and mostly dry again Monday.

- Isolated to scattered showers (15-35% coverage) and a couple
  weak storms over themountains through this evening. The showers
  remain possible through Monday morning for the northern high
  country.

- Pattern change arrives this week, with cooler temperatures
  finallyarriving by Tuesday.

- Main precipitation chances from late Tuesday through Wednesday,
  possibly continuing on Thursday. A few inches of mountain snow
  becoming increasingly likely, mainly above 10,000 feet.

&&

.DISCUSSION /Through Sunday/...
Issued at 150 PM MDT Sun Oct 11 2026

It will be another day in the 80s for the plains. Even with a few
more clouds today compared to previous days, temperatures are
forecast to be only a degree or two cooler with highs in the low to
mid 80s. A rather strong jet overhead will continue to strengthen
and bring breezy conditions to much of the area today. The high
country overnight could even see some gusts of 40-50 mph at the
highest elevations towards sunrise Monday. The moisture associated
with former Tropical Storm Rachel remains well off to our west.
Isolated to scattered showers are possible for the high country
today with the potential for these to continue into the overnight.
The northern high country (i.e. Jackson County) looks to be most
favored. Rainfall amounts look light with 0.2" at most and slightly
higher totals possible for the Park Range. There is a low risk for
some marginally severe wind gusts (~50-60 mph) associated with these
storms given the strong SW flow aloft.

Monday morning could be the fifth day in a row and 7 out of the last
8 days with record warm minimums for Denver (assuming this morning`s
low temperature holds through the end of the day). The current
forecast is 56 F which would break the record of 55 F set in 1996.
Expect more of the same for Monday with high temperatures only
dropping a few degrees into the upper 70s and low 80s for the plains
even with less clouds than today as the mid-levels cool a touch.
There could be a brief period of elevated fire weather conditions on
the far eastern plains Monday afternoon. Low rain chances will again
be possible for the northern high country, though coverage looks
isolated. PoPs increase on late Monday for the northern high country
and slowly spread eastward on Tuesday as the long-awaited upper
level low moves closer to our area.

Some changes to this rather stagnant pattern finally start on
Tuesday as a cold front pushes through late Monday into early
Tuesday. This will drop high temperatures on Tuesday into the 60s or
possibly even the upper 50s on the plains (except for our far
southeastern counties)- finally near average for this time of year.
The cold front is trending stronger than in previous forecasts.

Forecast models have started to converge on showing the upper level
low moving through Utah, western CO, and into our area by late
Wednesday. As a result, PoPs should remain at or above 50% across
much of the area for Wednesday. Increased cloud cover and rain will
mean that high temperatures on Wednesday for the plains will
struggle to make it out of the 50s with the high country stuck in
the 30s and 40s. Model guidance is trending even lower with high
temperatures for Tuesday and Wednesday with this latest forecast
package reflecting that change. This will likely be the coolest day
of the season so far! Some precipitation could linger for the area
on Thursday, but rain chances remain rather unclear as the
synoptic pattern becomes murky. The location of the deepest
moisture associated with the remnants of Hurricane Simon towards
the end of the week also complicates the forecast.

All ensemble members continue to show measurable precipitation
for the urban corridor with the average still around 0.5" or
slightly higher. There will of course be some variations once the
finer-scale details can be worked out over the next few days. The
northern mountains could have QPF closer to an inch or more given
the longer duration of precipitation there. The 12z ECMWF
ensemble guidance has trended up with QPF amounts for the urban
corridor and is now more in line with the GFS ensemble members,
which have been rather consistent over past few days. The
mountains and high country (mainly above 10,000 feet) are still on
track to receive a few inches of snow with the northern mountains
continuing to look the most favorable- perhaps reaching advisory-
level criteria. Ensemble guidance shows Friday continuing to stay
below average with warming temperatures- to a few
degrees above average for this time of year- for the weekend.

&&

.AVIATION /00Z TAFS through 00Z Tuesday/...
Issued at 548 PM MDT Sun Oct 11 2026

VFR will continue through the TAF period with skies becoming
clear after 06Z and remaining clear through Monday. A Denver
cyclone has formed north of Denver bringing south to southwest
winds to DEN and APA, while BJC is seeing north to northwest winds
on the backside of the cyclone. This cyclone is expected to break
down tonight with south to southwest winds returning to BJC. At
DEN, the current south winds will continue and may bend to the
southwest around 02Z due to outflow moving off the higher terrain.
Overall winds are expected to stay south to southwest at DEN and
APA through Monday morning at 10-20 knots, with occasional gusts
to 25 knots, mainly this evening and then again late Monday
morning (15-18Z). Wind forecast is highly uncertain after 18Z
Monday due to a deepening surface low over northeast Colorado.
Eventually the southerly winds will become north to northeast as
the low strengthens and sinks south across eastern Colorado.

&&

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

&&

$$

DISCUSSION...MV
AVIATION...BM

NWS BOU Office Area Forecast Discussion