300
FXUS65 KBOU 272004
AFDBOU

Area Forecast Discussion
National Weather Service Denver/Boulder CO
204 PM MDT Mon Apr 27 2026

.KEY MESSAGES...

- Low elevation rain showers/weak thunderstorms and mountain snow
  expected today and tomorrow.

- More active pattern continues through the week with multiple
  precipitation chances.

- Warmer and drier conditions expected by the weekend.

&&

.DISCUSSION /Through Monday/...
Issued at 157 PM MDT Mon Apr 27 2026

Latest satellite imagery shows vast improvements over this morning`s
dense fog that crept its way into metro Denver and the
surrounding suburbs for the morning commute. While some stratus
remain in place south of Denver and along the Palmer Divide, skies
over the northern plains have cleared out and allowed for
temperatures to warm into the mid 40s early this afternoon. Areas
along and just north of the Palmer remain rather chilly, with
observations showing things have yet to climb out of the 30s as of
11 am. Have lowered temperatures slightly in these areas to
account for the lack of surface heating in these locations.

Things finally start to pick up along the southern tier, bringing a
more active pattern across Colorado, with multiple precipitation
chances expected throughout the extended forecast period. Beginning
this afternoon, another shortwave is expected to move across the
Rockies that will bring mountain snow and rain showers to the lower
elevations. A few thunderstorms or even some thundersnow can`t be
ruled out this afternoon and evening as showers move from west to
east across the forecast area. Can`t rule out some localized heavier
convective snow showers in the high country later today and tomorrow
that could make for some slick conditions, but most impacts would be
across the high mountain passes, and generally north of I-70. Snow
totals between today and Tuesday will range from 4 to 7 inches
mainly above 9,000 feet, with some locally higher amounts at our
highest elevations, and some lighter amounts down to elevations
around 8,000 to 8,500 feet. Most areas across the plains that see
showers can expect a few hundredths, but some areas may see some
locally higher amounts up to around a half inch between today and
tomorrow.

By Wednesday, zonal flow aloft will start to decrease and
temperatures will warm up to near seasonal values. Another shortwave
is progged to move across the Rockies that will bring more afternoon
showers and weak thunderstorms, with continued light snow showers to
the mountains. A cold front is expected to move across the forecast
area Wednesday evening that will bring cooler temperatures for
Thursday and upslope flow behind it. This will bring widespread
precipitation chances to the forecast area, but highest PoPs are
expected for the southern foothills and Palmer Divide through
Thursday.

While there are still uncertainties with the exact track and
strength of the upper-level low expected to move across Baja
Thursday, trends do now seem to agree that this will take a more
southern track than previously advertised, and areas south of us
will benefit from the higher precipitation amounts. While we may
miss out on the highest QPF amounts, the latest NBM does show our
southern tier of counties still has a 60-80% chance of 24-hour QPF
totals greater than .5" through Thursday evening. Due to the
continued elevated moisture and cooler temperatures, no critical
fire weather conditions are expected through the week! A warming
trend looks likely on the other end of the mid- to end-week system
that will bring warmer temps and drier conditions for the
weekend.

&&

.AVIATION /18Z TAFS through 18Z Tuesday/...
Issued at 1201 PM MDT Mon Apr 27 2026

Low clouds are still lingering at BJC and APA this afternoon with
DEN getting a brief period of scattered clouds before ceilings
redevelop shortly. Broken clouds around 6,000 feet or lower are
expected for the entire forecast period which may lead to impacts
on arrival rates.

Convection over the mountains will continue to develop this
afternoon and will spread showers and perhaps a weak thunderstorm
across the terminals this afternoon and evening. With relatively
cool and stable conditions near the surface, microbursts are not
expected to impact the terminals. While there could be a couple
cloud to cloud lightning strikes near the airports, the impacts
from any storms that form would be minimal. Otherwise, winds will
remain weak throughout the afternoon and evening.

Southeast winds will develop overnight at all terminals. Usually,
a southeast wind provides just enough downslope such that no fog
or very low clouds develop at DEN and APA. However, there could be
a brief period from 12-15Z Tuesday where the winds weaken and fog
develops at all terminals. A FEW001 group was added to indicate
the possibility of fog with the chance of fog at around 20 percent
at this moment.

There will be another round of showers or weak thunderstorms
Tuesday afternoon. The impacts from these showers or weak storms
will be closer to impacts from scattered rain showers so -SHRA was
included in the TAF.

&&

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

&&

$$

DISCUSSION...9
AVIATION...Danielson

NWS BOU Office Area Forecast Discussion