National Weather Service Forecast Discussion

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993
FXUS65 KBOU 021116
AFDBOU

Area Forecast Discussion
National Weather Service Denver/Boulder CO
416 AM MST Mon Nov 2 2026

.KEY MESSAGES...

- Snow likely (> 80% chance) for the mountains through most of
  today. Snow level falls to 9,000 to 9,500 feet this morning and
  down to 8,000 feet this afternoon.

- Mountain roads will become slippery in spots above 8,500 feet,
  especially through mountain passes.

- Scattered to numerous rain showers and cooler temperatures for
  the plains for today. A few snowflakes possible for the Palmer
  Divide on Monday night. Very windy plains this afternoon and
  tonight.

- Another chance for some rain and snow for the mountains on
  Wednesday bringing light precipitation amounts.

&&

.UPDATE...
Issued at 240 AM MST Mon Nov 2 2026

Areas of dense fog was occurring from along and south of a Greeley
to Fort Morgan line and was moving into portions of the nern
Denver Metro area. Expect this dense fog will linger around the
Denver Netro thru 13z or 14z before lifting. If it back builds
further west may have to issue a dense fog advisory.

Meanwhile there is some threat of high winds across the plains
late this afternoon through tonight. Boundary layer winds are
fcst around 50 kts and if those mix down will likely see some
gusts to 60 mph mainly over northeast Weld, Logan, Morgan,
Washington and portions of Lincoln county.

&&

.DISCUSSION /Through Sunday/...
Issued at 1122 PM MST Sun Nov 1 2026

The next storm system has started to affect our area over the last
few hours with some light rain/snow showers across the high country
and light rain showers for the majority of the plains. Some light
rain/snow showers continue at this hour for the Medicine Bow Range
and light rain showers for the far northeastern plains. With the
saturated grounds from the Sunday evening rain, fog is possible once
again. Favored locations look to be northern Colorado and possibly
extending into the northern metro and east to DIA. Have held off on
any highlights given the uncertainty with how widespread any fog
would be, but an advisory may be needed if confidence increases
overnight. Any fog would quickly lift as the cold front moves
through on Monday morning.

The trough that will affect our weather over the next 24-36 hours is
currently centered over the Great Basin and should quickly push
through Colorado by late Monday. Good moisture continues to advect
into our area with southwest flow in the mid and upper levels. We
expect coverage of precipitation to increase by Monday morning
through the early afternoon as lift increases and the cold front
pushes through from north to south. The cold front moves through the
metro around 6-9am and looks to clear our area by about 2pm Monday.
In its wake, afternoon temperatures should struggle to make it out
of the upper 40s for much of the plains given the clouds in place
and the chance for showers. Some scattered showers could linger on
the plains through Tuesday morning with some upslope continuing.

QPF is very similar to the last forecast package. Ensemble guidance
continues to coalesce on 0.1-0.4" rainfall for the Denver metro with
some locally higher amounts possible mainly for the southeast
portions of the metro. Similar rainfall totals look possible for
most of the plains with some signal that western Washington County
and adjacent areas could see the most rainfall. This is likely due
to a rather deep upslope component (northerly winds) from the
surface up to 500 mb behind the cold front. For the northern high
country, many areas should see 0.50-0.75" QPF with some higher
amounts possible. Lesser amounts are expected for the rest of the
high country.

As for snow, snow showers will start to increase in coverage over
the next few hours for the high country. Colder air will continue to
filter in aloft quickly lowering snow levels. Snow levels are
currently around 10,500 feet, but quickly drop through the overnight
to around 9,250 feet by Monday morning. Snow levels will continue to
drop to near 7,500-8,000 feet or even a bit lower by Monday evening.
The Palmer Divide still has a chance for some snowflakes to mix in
on Monday evening as precipitation chances start to wind down. The
Winter Weather Advisory goes into effect early this morning and
lasts through late Monday night. The forecast remains on track with
3-8 inches of snowfall expected in general. As previously noted,
northerly flow is expected as the trough pushes through. In this
flow pattern, the northern mountains continue to look most favored
in our area for the highest snowfall totals with some totals greater
than 9 inches possible, particularly at the highest elevations. DESI
probabilities highlight this potential well with a 50% chance or
greater of snowfall totals exceeding 6 inches for the Park Range,
northern Gore Range, and Medicine Bow Range. Note that higher totals
are still possible for areas along the Front Range Mountains
including Summit County and RMNP, but much less likely.

Monday and even Tuesday will also feature some breezy conditions for
the plains. DESI probabilities show at least a 40% chance for wind
gusts exceeding 55 mph on Monday afternoon and evening across our
plains. Given the lack of subsidence and momentum transfer, we have
held off on any wind highlights. Most locations on the plains should
see gusts of 35-55 mph with isolated locations having the potential
for gusts of 55-60 mph Monday afternoon, evening, and into early
Tuesday. Wind gusts could still reach 40-50 mph for the far eastern
plains on Tuesday afternoon.

After the passage of the trough late Monday into early Tuesday,
ridging quickly looks to take its place. Tuesday will be a warmer
day with high temperatures near average for this time of year- in
the upper 50s. High temperatures should stay near average for the
rest of the week. Another low looks to track through our area on
Wednesday. The majority of models bring the chance for another round
of light snow showers for the high country and possibly some rain
showers for the plains. Any accumulation continues to look rather
unimpressive with this system at this time. Thursday and Friday
should be dry with westerly flow aloft and near-normal temperatures.

By the weekend, there could be another cold front cooling
temperatures down as hinted in the ECMWF AI ensembles. Other
ensemble guidance keeps high temperatures in the upper 50s and
possibly warming into the low 60s for the plains on the back half of
the weekend. A trough could graze us to the east putting us in the
right exit region of the jet- where subsidence is favored.
Therefore, regardless of the temperatures, the weekend is trending
drier.

&&

.AVIATION /12Z TAFS through 12Z Tuesday/...
Issued at 407 AM MST Mon Nov 2 2026

Dense fog was affecting APA and DIA early this morning and will
continue thru 14z before gradually lifting.  Satellite shows
the wrn extent of this fog east of I-25 and it doesn`t look like
it will affect BJC.

By 15z a cold front will move across the area with gusty north
winds behind it. Gusts from 30-35 mph will occur from late morning
thru the afternoon with slightly lower speeds at BJC. In
addition, will see rain showers between 15z and 20z as well.
Ceilings will be down to 4500 ft with a period of lower ceilings
down to 2500 ft where heaiver rainfall occurs. Visbility will stay
mainly in the 3-5 mile range with the rain.

After 20z will see rain showers end from north to south with most
activity done by 23z. Ceilings will be in the 5000-6000 ft range
thru the evening hours. North winds will remain gusty at APA and
DIA through 04z with a slow decrease in speeds overnight.

&&

.BOU WATCHES/WARNINGS/ADVISORIES...
Winter Weather Advisory until midnight MST tonight for COZ031-
033-034.

Dense Fog Advisory until 8 AM MST this morning for COZ040-043-
045.

&&

$$

UPDATE...RPK
DISCUSSION...MV
AVIATION...RPK

NWS BOU Office Area Forecast Discussion