437
FXUS65 KBOU 200542
AFDBOU

Area Forecast Discussion
National Weather Service Denver/Boulder CO
1042 PM MST Wed Nov 19 2025

.KEY MESSAGES...

- Accumulating snow is likely (70-80%) across the Front Range
  mountains and foothills. Generally 1-6" of snow is expected with
  the highest amounts in the Front Range Mountains. Only a slight
  chance (20%) of snow for the Denver metro and plains. The
  northern plains and Palmer Divide have a 40% chance of seeing
  snow with minimal snow amounts expected.

- The plains will see widespread rainfall late Thursday through
  early Friday. Amounts over an inch of rain are possible mainly
  from Limon to Sterling and nearby areas.

- Another rain event is possible late Sunday across the plains.
  Light snow is likely in the mountains and foothills.

- Turning cooler around Thanksgiving with the potential for a
  couple very light snowfall events during the latter half of
  Thanksgiving week.

&&

.DISCUSSION /Through Wednesday/...
Issued at 250 PM MST Wed Nov 19 2025

It`s hard to believe it`s the week before Thanksgiving and we will
be talking about two rain events for the Denver metro. But it`s
been a warm month that`s running 8.5 F above normal in Denver.

A trough that will bring precipitation to our area on Thursday is
currently over the California/Arizona border. There are plenty of
thunderstorms in Arizona which is indicative of the moisture in
the area. This trough will weaken, become more negatively tilted,
and will end up in eastern Colorado by Friday morning. A wave of
precipitation is expected to form over southeast Colorado Thursday
morning and will become more widespread and intense as it moves
northward into our forecast area. A deformation zone on the
northwest side of the trough will help to keep the precipitation
going in northeast Colorado through Thursday night and into
Friday. The difficulty will be determining how much precipitation
will fall and where the heaviest amounts will be. Models like the
NAM and HRRR have consistently been forecasting significant
precipitation for November standards. Each model has a wide swath
of rainfall around 1.5" across the plains. Meanwhile, the ECMWF
has been consistent with showing about a quarter inch of rainfall
in the Denver metro and around a half inch of rain across the
plains. The forecast was trended towards the ECMWF for QPF amounts
and the PoPs were increased across our CWA since the likelihood
of precipitation is increasing. While the QPF was trended towards
the ECMWF, the higher forecast QPF amounts are certainly possible
given the ample moisture arriving in our area with 40+ F dew
points expected.

The other forecast uncertainty in this event will be
precipitation type and snow level. As previously mentioned, dew
points in the low 40s will advect over the eastern plains and this
will mean precipitation will likely (80% chance) fall as all
rain. However, if precipitation amounts are more intense that
expected, areas near the Cheyenne Ridge and Palmer Divide could
receive some light snowfall late Thursday night. Across the
higher terrain, the snow level will be around 7,000-7,500 feet.
The Front Range Mountains and higher Foothills will see 1-6" of
snow. If the higher end precipitation values occur, snowfall
amounts could reach up to 10" especially in Rocky Mountain
National Park.

Brief ridging will move over Colorado late Friday into Saturday.
Friday night through Sunday morning will be dry with slightly
above normal temperatures.

The model trend has been very consistently moving a cut-off trough
over the Desert Southwest farther north on Sunday. The majority of
models take the center of the 500 mb trough into southeast
Colorado. This will bring a chance of precipitation to our
forecast area. The latest NBM doesn`t have this new data in it
so PoPs were increased on Sunday night to include a 30-40% chance
of precipitation across most of our area. This system will be
similar in regard to precipitation type as the first one. Rain is
likely across the plains and light snow is possible in the
mountains.

A period of ridging will move over Colorado on Monday and into
Tuesday with dry weather and normal temperatures expected. A
trough will bring cooler temperatures by Thanksgiving with below
normal temperatures expected. There will be multiple chances of
very light snowfall during the latter half of next week.

&&

.AVIATION /06Z TAFS through 06Z Friday/...
Issued at 1039 PM MST Wed Nov 19 2025

VFR through early afternoon, with steadily lowering
ceilings/visibility by Thursday evening into Thursday night.
Drainage flow overnight tonight will turn light and variable late
Thursday morning, followed by a shift to the east or northeast as
upslope begins to deepen ahead of an approaching storm system.
Moisture is expected to pivot back towards the terminals near or a
little after 00z, with SHRA developing. Some guidance has heavier
rain and/or LIFR cigs at times overnight, but confidence in either
of those is fairly low. Either way, expect generally MVFR to IFR
conditions Thursday night which will likely persist through at
least the first half of Friday.

&&

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

&&

$$

DISCUSSION...Danielson
AVIATION...Hiris