National Weather Service Forecast Discussion

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012
FXUS65 KBOU 271138
AFDBOU

Area Forecast Discussion
National Weather Service Denver/Boulder CO
538 AM MDT Mon Apr 27 2026

.KEY MESSAGES...

- Areas fog this morning, locally dense.

- 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 /12Z TAFS through 12Z Tuesday/...
Issued at 538 AM MDT Mon Apr 27 2026

A cold front will bring north winds and cooler temperatures this
morning. Fog is expected to redevelop behind the front with
visibility falling to a quarter mile or less. As the cooler air
behind the front deepens, a deeper mixed boundary layer is
expected, which should cause the fog deck to lift, leaving a low
ceiling in its place.

After the fog and lower clouds dissipate, we will likely see 4,000
to 6,000 foot ceilings due to the moist airmass and an easterly
upslope flow. Scattered rain showers are expected to form after
18z and persist through the evening, 06Z Tuesday. After this,
chances for showers decrease but clouds will lower and linger into
Tuesday morning.

&&

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

&&

$$

DISCUSSION...66
AVIATION...12

NWS BOU Office Area Forecast Discussion