Area Forecast Discussion
Issued by NWS Denver/Boulder, CO

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
000
FXUS65 KBOU 260131
AFDBOU

Area Forecast Discussion
National Weather Service Denver/Boulder CO
731 PM MDT Mon Mar 25 2024

.KEY MESSAGES...

- Today`s temperatures will be well below seasonal normals, but
  will warm up somewhat on Tuesday.

- Light snow showers in the mountains Tuesday into early Wednesday
  with a slight chance of snow showers across the plains on
  Tuesday.

- Drier conditions return for Thursday through Saturday with warmer
  temperatures.

&&

.SHORT TERM /Through Tuesday/...
Issued at 243 PM MDT Mon Mar 25 2024

The low clouds and very light snow showers just do not want to go
away across the plains this afternoon. These will persist until
around sunset and the PoPs were increased across the plains to get a
mention of snow showers especially in areas favored during northerly
upslope flow. Looking at visible satellite, low clouds are
dissipating over Wyoming and far northern Colorado. So there is
increasing confidence that the low clouds and snow showers will
end around sunset. Over the mountains and foothills, very weak
instability has helped to create a few snow showers. These may
persist further into the evening but will dissipate by midnight.

Tonight will be quite chilly across our forecast area. The plains
will see lows in the teens with some of the usual cold spots like
Limon and Monument Hill reaching the singe digits. Across the higher
mountains, lows will reach below 0.

On Tuesday, there will be west-northwesterly flow aloft with quite
cold mid level temperatures. This cold air aloft will help to create
very steep lapse rates across the higher terrain after some morning
sunshine. This instability along with a very weak shortwave trough
moving through, will create convective snow showers over the higher
terrain. There could be brief moderate snowfall in these showers and
they shouldn`t last for very long. Overall snow accumulation in the
mountains should be less than 3 inches. During the late afternoon,
these snow showers will make their way onto the I-25 corridor.
Little to no snow accumulation is expected due to temperatures in
the 40s. PoPs were increased to account for these snow showers.
Otherwise, it will be a cool day with temperatures roughly 10-15 F
below normal.

&&

.LONG TERM /Tuesday night through Monday/...
Issued at 243 PM MDT Mon Mar 25 2024

Wednesday, an flat upper level ridge will slowly move eastward into
Colorado. This will gradually decrease moisture across the high
country into the afternoon. With sufficient lapse rates and some
residual moisture, expect some light, lower coverage snow showers in
the mountains that afternoon/early evening. The warming trend in
temperatures also begins Wednesday with the pattern change.
Temperatures aloft warm a few degrees from Tuesday, helping brings
highs into the 50s across the the lower elevations. Higher
elevations will generally see highs in the 20s and 30s with 40s for
the foothills.

Flow aloft transitions to more WSW by Thursday afternoon in response
to a trough pushing into the Pacific Northwest. Ensemble guidance
show a weak embedded wave move through the southwest flow in the
late Thurs-Fri timeframe. There should be enough moisture to support
snow showers across the mountains and high country. Lapse rates are
fairly weak also, so any showers will be low coverage and light.
Westerly component (downslope) flow will keep things drier across
the plains. Highs warm even further on Thursday with high in the 60s
across the lower elevations. Southwest flow aloft continues
Friday and into the weekend with some chances for orographic snow
showers across the mountains and above normal temperatures for
the plains. Temperatures lean above normal across the lower
elevations with even a shot at highs near 70 by Sunday.

Confidence in the upper level pattern and how it progresses
decreases for the end of the weekend into early next week. Ensemble
guidance generally depicts a positively tilted, elongated trough
moving eastward toward Colorado. There is disagreement on how a
northern branch upper trough interacts and phases with the more
south trough. There is some agreement with moisture increasing by
the end of the weekend with continued SW flow aloft. This will
bring another round of snow for the mountains by Sunday evening.
Details are still too fuzzy to talk amounts/impacts until the
pattern becomes more clear.

&&

.AVIATION /00Z TAFS through 00Z Wednesday/...
Issued at 723 PM MDT Mon Mar 25 2024

Low and mid level clouds will decrease this evening with light
drainage winds this evening. A push of southeasterly winds will
then arrive between 07-09Z. Winds will likely be light and
variable during the day tomorrow. Afternoon convective snow
showers may impact the terminals. As a result visibility and
ceilings could drop below MVFR briefly.

&&

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

&&

$$

SHORT TERM...Danielson
LONG TERM...Mensch
AVIATION...Cooper


USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.