307
FXUS65 KBOU 270553
AFDBOU

Area Forecast Discussion
National Weather Service Denver/Boulder CO
1153 PM MDT Sun Apr 26 2026

.KEY MESSAGES...

- A Winter Weather Advisory remains in effect for the mountains
  overnight tonight for lingering snow showers.

- The cooler and more moist weather pattern will continue all this
  coming week.

&&

.DISCUSSION /Through Sunday/...
Issued at 1144 PM MDT Sun Apr 26 2026

There are still a few showers moving northeastward across the
plains at this time.  There hasn`t been any lightning detected
with the convection over the CWA since late this afternoon. Radar
pictures, observations and web cameras are showing areas of light
snow over the mountains here and there. Temperatures were in the
upper 30s to lower 40s over the plains and lower foothills, with
a few observations showing fog.

The cooler, wetter pattern looks to continue for the CWA much of
this coming week, with no fire weather concerns expected.

A weak upper trough will move across the CWA tonight into Monday
morning with areas of light snow in the mountains.  Will leave
the snow advisory going over the high mountains overnight. The
plains will see a cold front push across late tonight with upslope
flow behind it. Temperatures will stay in the 50s over the plains
on Monday with showers for most areas along with a few late day
thunderstorms. Precipitation amounts will mostly be light.

Another weak upper trough will move across Colorado Tuesday morning
continuing the cool and moist weather pattern for the CWA. Highs on
Tuesday will stay in the 50s again with showers and a few storms for
much of the CWA in the afternoon.

Strong zonal flow aloft will move in on Wednesday with slightly
warmer temperatures, 60-65 over the plains, and the best chance of
the showers along with a few storms over the southern half of the
CWA.

Thursday looks to cool down a bit with showers over most of the
forecast area along with a few late day thunderstorms. Highs will
be in the 50s over the plains again on Thursday.

With the cool temperatures expected through the last day of the
month; Thursday, April will be a colder month than March was in
Denver this year.

For the later days, Friday through Monday, latest model runs show
upper troughing over Colorado Friday into Saturday morning. By
Saturday afternoon, upper ridging gets over the state and it
continues through Monday.  Decent moisture is around on Friday with
the trough, then the airmass dries out Saturday through Monday with
limited late day alpine showers only.  Temperatures will warm up to
above seasonal normals Saturday, Sunday and Monday, with 70s
returning to the plains on Sunday.

&&

.AVIATION /06Z TAFS through 06Z Tuesday/...
Issued at 1138 PM MDT Sun Apr 26 2026

It will be a challenging fog and cloud forecast for rest of
tonight and Monday morning. A moist airmass covers the area with
the temperature/dew point spread less than 5F degrees. Skies are
mostly cloudy at this time and will limit traditional cooling and
the threat for fog. Clouds are expected to decrease overnight,
with radiational fog forming after 08-09Z. A cold front brings
north winds and cooler temperatures 10-12Z. If fog hasn`t
developed ahead of the front, it should form as the front pushes
through due to added cooling with little to no loss of moisture.
As the cooler air behind the front deepens, a better mixed
boundary layer is expected, which should cause the fog deck to
lift, leaving a low ceiling in its place.

After the low clouds dissipate 16-18Z, it is unclear if we will
have scattered or broken low/mid level clouds. The GFS keeps
ceilings below 6,000 feet all day, while the NAM/HRRR show
scattered clouds around and after 18Z. The next round of showers
moves in mid afternoon, 20-21Z. Due to the moist airmass and an
easterly upslope flow, went with the cloudier scenario. The
showers are expected to persist through the evening and end around
06Z Tuesday. After this, more low clouds are expected for Tuesday
morning.

&&

.BOU WATCHES/WARNINGS/ADVISORIES...
Winter Weather Advisory until 6 AM MDT Monday for COZ031-033-034.

&&

$$

DISCUSSION...66
AVIATION...12

NWS BOU Office Area Forecast Discussion