130
FXUS65 KBOU 022017
AFDBOU

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

.KEY MESSAGES...

- Above average temperatures and dry conditions expected for the
  weekend.

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

-Significant snowfall accumulations are possible (60% chance) in
 the mountains Monday night through Wednesday. Chances are
 increasing for snow along the I-25 corridor Tuesday evening into
 Wednesday.

&&

.DISCUSSION /Through Saturday/...
Issued at 217 PM MDT Sat May 2 2026

It is a nice sunny day across Colorado today with an upper-level
ridge bringing quiet weather and warm temperatures into the region
through tomorrow. Afternoon temperatures today and tomorrow will
climb into the 60s and 70s at low elevations. Relative humidities
will be dry both days, with values dropping into the low teens and
perhaps the single digits. Despite the low RH values, we are not
overly concerned about fire weather due to the very light winds in
place.

We have some 30-40% PoPs over the Denver metro area and I-25
corridor on Monday afternoon as Pacific moisture ahead of an
approaching trough continues to be advected over the area and
daytime destabilization occurs. However, most of these convective
showers will be high-based or virga. Model soundings suggest
DCAPE values ~600 J/kg due to the dry air at the low levels,
indicating that these high-based showers will also be able to
produce some gusty winds. A strong cold frontal passage is
expected to arrive Monday evening, bringing an initial surge of
moist, cool air, and enough lift for additional rain showers to
develop over the plains, as well as snow showers over the northern
Front Range and Cheyenne Ridge. Snow levels should remain above
8,000 ft along and behind the front.

A deep Pacific low will continue to track east inland over Southern
California and Arizona, becoming a shortwave trough before possibly
phasing with the strong upper-level trough sliding south over the
northern plains on Tuesday. While there is still some uncertainty
regarding how these synoptic features will evolve, ensemble guidance
has been trending towards a phased solution, which would put our CWA
in a decent position for measurable rain and snow Monday night
through Wednesday.


The main surge of cold air will arrive late Tuesday morning, which
is when the snowfall will begin to ramp up over the Front Range.
Snow levels look to fall from around 8,000 feet Tuesday midday, to
6,000 ft by late afternoon. The eastern Colorado plains and Denver
metro area will likely remain too warm for snow during the day, but
we lowered daytime temperatures down to the upper 30s/low 40s given
that we expect stratiform-like rain coverage most of the afternoon.
Temperatures will continue to gradually cool down through the day on
Tuesday, with a transition to snow over the Denver metro area early
Tuesday evening.

While it is too early to tell with high certainty, the current model
guidance and ingredient-based assessment of this system suggests at
least light snow (T-2") accumulations on grassy/elevated surfaces
over the Denver metro area, with higher amounts (2-4") over the
Palmer Divide due to upslope enhancement. The mountains will
likely see more significant accumulations (8-13"), with the
highest amounts occurring over the Front Range, especially above
8,000 feet. The left exit region of an upper-level jet streak will
be positioned over the eastern plains Wednesday morning,
continuing to favor upward motion through at least Wednesday
morning. However, snow should gradually diminish Wednesday
afternoon as northerly flow begins to bring drier air into the
region. For now, enough cloud cover Wednesday night into Thursday
morning should keep low temperatures from plummeting into the 20s
across the I-25 corridor, but if it dries out sooner than
currently in model guidance, most of the area could be in for a
deep freeze Thursday morning.


&&

.AVIATION /18Z TAFS through 18Z Sunday/...
Issued at 1144 AM MDT Sat May 2 2026

Variable, weak winds are expected again at DIA this afternoon.
Pretty normal drainage winds are expected by 04Z this evening
continuing overnight.  There will be no ceiling issues.

&&

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

&&

$$

DISCUSSION...AA
AVIATION...66

NWS BOU Office Area Forecast Discussion