Area Forecast Discussion
Issued by NWS Denver/Boulder, CO

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720
FXUS65 KBOU 030554
AFDBOU

Area Forecast Discussion
National Weather Service Denver/Boulder CO
1154 PM MDT Sat May 2 2026

.KEY MESSAGES...

- Above average temperatures and dry conditions expected for
  Sunday.

- Unsettled weather returns Monday night through Wednesday with
  increasing chances for rain showers and some snow for the plains.

- Significant snowfall accumulations are possible (70% chance) in
  the mountains Monday night through Wednesday. Chances are
  increasing for accumulating snow along the I-25 corridor
  Tuesday evening into Wednesday.

&&

.DISCUSSION /Through Saturday/...
Issued at 1150 PM MDT Sat May 2 2026

An upper level ridge will continue to influence our weather for one
more full day. Temperatures on Sunday morning will be near average
in the mid to upper 40s. Sunday will be another above average day
with highs in the mid to upper 70s for the plains with a low (20-30%)
chance for light mountain snow and increasing mid to high level
cloud cover by late afternoon. Monday will also feature mid to
high level cloud cover and high temperatures in the 70s. Monday
afternoon will bring the first signs of this system to our region.
High-based showers and virga are possible (30-40%) on the plains
as well as light mountain snow. Model soundings show DCAPE values
as high as 800 to 1000 J/kg, so any shower could produce some
gusty outflow winds.

An upper level low will be located over California on Monday
afternoon and moving east throughout the week. Meanwhile, the jet
stream will be moving south out of Canada with at least a piece of
it moving through CO/WY on Tuesday night and Wednesday. Model
consensus places us in the left exit region of this jet by Wednesday
morning. Models/ensemble clustering have come into better agreement
over the last 36 hours, increasing the likelihood of these two
features phasing together, which would put our forecast area in a
favorable position for lift, frontogenesis, and thus for measurable
precipitation. As a cold front approaches and moves through the
forecast area on Monday night, winds will become gustier and
precipitation will become more widespread with rain for the plains
and snow for the mountains initially. A second surge of cold air is
expected on Tuesday into Tuesday night. Thus, high temperatures on
Tuesday and Wednesday could range from the mid 30s to mid 40s for
the Urban Corridor and plains given increased cloud cover and
precipitation chances. Temperatures on Tuesday night could fall
anywhere between the upper 20s and low 30s. Have continued to nudge
temperatures down for Tuesday AM through Wednesday PM. As of now,
projected snow levels will be around 7500 feet on Tuesday morning
and drop to or a little below 5500 feet by late Tuesday night. A
subtle trend in forecast temperatures in either direction could make
a substantial difference in snow levels and thus potential snow
accumulations for the lower elevations.

Precipitation will last into the day on Wednesday before coming to a
close by Wednesday afternoon and evening. As of now, we are
confident that the heaviest snowfall (8 to 13 inches) would be for
the mountains making travel difficult for Tuesday through Thursday
morning. There is increasing confidence in several inches of snow
accumulation and some travel impacts for the foothills and Palmer
Divide. Upslope flow for the Palmer Divide would be favorable for
localized higher accumulations as compared to the rest of the I-25
corridor. Finally, the Denver metro and adjacent plains will start
as rain on Monday night and Tuesday, but could see a switchover to
snow on Tuesday night leading to at least some snow accumulations on
grassy surfaces of a trace to 2 inches. Of note, nearly 90% of
ensemble members now show at least a trace of snow for the Denver
metro and a 70% chance of at least one inch of snow accumulation.
While confidence has increased that the Urban Corridor and adjacent
plains could see some accumulation, exact snowfall amounts remain
uncertain. Overall, total QPF amounts of 0.5" to 1" are expected at
this time with isolated higher amounts, especially for the
mountains, foothills, and the Palmer Divide. Regardless of ptype,
this system is much needed given that the majority of the area is
currently in extreme to exceptional drought. Headlines could be
needed within the next 24 to 48 hours. Finally, model guidance is in
good agreement of temperatures returning back to the 70s late week
as upper level ridging starts to build back in.

&&

.AVIATION /06Z TAFS through 06Z Monday/...
Issued at 1116 PM MDT Sat May 2 2026

VFR conditions will prevail for all terminals through the TAF
period. Robust SW drainage flow of 08-12 kts will continue through
early to mid morning Sun (W for KBJC), then begin to rotate
clockwise starting near 15Z and becoming N/NW by around 17Z, +/- 2
hours. Wind direction is more uncertain for late afternoon and
early evening, but will eventually return to drainage overnight.

There will be an increase in mid-level cloud cover mid-afternoon
as SCT cumulus develops. ISO virga is not out of the question, but
moisture will be highly limited and thus the outflow wind
potential doens`t appear high enough to warrant a PROB30 group at
this time.

&&

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

&&

$$

DISCUSSION...MV
AVIATION...BRQ