697
FXUS65 KBOU 031125
AFDBOU

Area Forecast Discussion
National Weather Service Denver/Boulder CO
525 AM MDT Sun May 3 2026

.KEY MESSAGES...

- Above average temperatures and dry conditions expected for
  Sunday.

- Widespread precipitation is expected Monday through Wednesday,
  with increasing confidence in moderate to heavy snow and
  significant travel impacts for portions of the mountains and
  foothills Tuesday into Wednesday.

- Rising confidence in the potential for snow accumulations across
  the lower elevations as well, but considerable uncertainty
  remains regarding amounts and roadway impacts.

&&

.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 /12Z TAFS through 12Z Monday/...
Issued at 519 AM MDT Sun May 3 2026

VFR conditions will prevail for all terminals through the TAF
period, with some increase in mid to high-level clouds AOA 120
into the afternoon.

SW drainage winds this morning should see a quick transition to
prevailing NW flow mid morning, rotating clockwise 15-17Z. There`s
a distinct possibility (close to a 30% chance) of a period of
gustier winds for KDEN mainly after 20Z, but confidence is
marginal and these are unlikely to be accompanied by -SHRA given
quite high cloud bases. Potential for gusts is slightly higher for
KBJC, where a few gusts to around 17-20 kts will be possible late
morning through the afternoon.

Otherwise, expect a return to drainage flow nearing midnight
tonight, with some uncertainty in wind directions for the evening
hours.

&&

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

&&

$$

DISCUSSION...MV
AVIATION...BRQ

NWS BOU Office Area Forecast Discussion