National Weather Service Forecast Discussion

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011
FXUS65 KBOU 082333
AFDBOU

Area Forecast Discussion
National Weather Service Denver/Boulder CO
533 PM MDT Wed Apr 8 2026

.KEY MESSAGES...

- Scattered showers Thursday afternoon/evening. Rainfall amounts
  will be light (less than 0.10").

- A brief cool down Friday with a 20-30% chance for light rain.

- Warm and mostly dry for the weekend. Scattered showers possible
  Saturday, mainly over the mountains. Dry Sunday.

- A spring storm possible Tuesday/Wednesday with heavier
  precipitation amounts possible.

&&

.DISCUSSION /Through Wednesday/...
Issued at 201 PM MDT Wed Apr 8 2026

Cold front has back southwestward much quicker thanthe models
indicated. High temperatures lowered a few degrees earlier for
areas behind the front. Isolated, high-based showers are still on
track for this afternoon and early evening. Low level moisture
increased behind the front, but it`s shallow and won`t help with
wetting rainfall. Chances for measurableprecipitation remain low,
less than 10 percent. Gusty outflow winds up to 30 mph will be
possible under and near the high-based showers.

Thursday`s forecast is tricky regardingPoPs. We have an upper
level ridge building over the region, but it appears a weak wave
passes underneath it. This combined withsteep lapse rates is
expected to result in scattered showers during the afternoon and
evening. A weak front tracks southward duringthe evening, which
could increase activity. Moisture is again limited, so any
rainfall reaching the ground is expected to be light, with
precipitationamounts less than a tenth of an inch, and in most
cases less than 0.05 (in).Gusty outflow winds around 35 mph will
be possible with the showers. Northeast low level flow behind the
front continues to increase low level moisture through Thursday
night. Low clouds (and possibly drizzle and fog) are expected to
develop over the eastern plains late Thursday night and into
Friday morning.

It will be cooler Friday over the northeast plains where low
clouds are expected to persist through the day. Gusty south to
southeast winds will develop over eastern Colorado. This should
lead to the development of a Denver cyclone. Northerly flow on the
backside of it will pull cooler air southwestward, so northern
parts of the I-25 corridor may struggle to reach 60 degrees.
Another round of high-based isolated/scattered showers will be
possible during the afternoon, though any rainfall will likely be
light.

On Saturday, southwest flow aloft will prevail. A lee-side
surface trough forms over eastern Montana, eastern Wyoming, and
far northeast Colorado. This, combined with the increasing
southwest flow aloft will lead to gusty south winds. A shortwave
trough embedded in the southwest flow aloft lifts northeastward
across the central Rockies. Given the current projected track,
western and centralColorado will see scattered to numerous
showers with this system. Farther east, scattered high-based
showers are expected for the Front Range and eastern plains.
Temperatures rebound under this pattern with highs reaching the
70s across northeast Colorado.

Southwest flow aloft continues Sunday around an upper level low
slowly moving east across northern California. Subsidence behind
Saturday`s system will prevail bringing dry conditions to the
area. Isolated high- based showers are possible over the higher
terrain during the afternoon, but little to no rainfall is
expected. South to southwest winds are expected to increase during
the day as flow aloft increases. Depending on the strength of
the winds and how low relative humidity falls, fire weather may be
a concern. Temperatures remain warm with highs expected to reach
the 70s again.

For Monday through Wednesday, the upper level low to the west
will slowly progress eastward. Southwest flow aloft continues
Monday ahead of the system. Moisture begins to increase with a
the best chance for showers over the mountains. The best chance
for precipitation with this system comes Tuesday as it tracks
across the Four Corners. There is still considerable uncertainty
regarding this system as models vary on the strength, timing, and
track. However, models generally agree that this upper level low
will track over or near the Central Rockies on Tuesday. A subset
of the ensemble still shows it cold enough for snow across the
lower elevations. The chance for precipitation decreases Wednesday
as the upper level low is expected to move east of the region.
Temperatures begin to recover with highs reaching the 60s across
northeast Colorado.

&&

.AVIATION /00Z TAFS through 00Z Friday/...
Issued at 527 PM MDT Wed Apr 8 2026

VFR conditions are expected to prevail for all terminals through
the TAF period.

Gusty winds have largely subsided at this hour, and winds will
continue to veer E to SE to S through the evening at KDEN/KAPA
with drainage flow continuing overnight. KBJC will be light and
VRB during this period.

Daytime mixing is expected to favor development of relatively
light 08-11kt NE/NNE winds beginning 18-19Z Fri at all of the
terminals. Between 19-20Z, mid-level cumulus development and
associated virga and -SHRA is anticipated, with this scattered
activity persisting through at least 01Z, and possibly as late as
03Z, being most numerous and consistent in the vicinity of KDEN
and KBJC, for which TEMPO groups have been introduced.
Convective-induced gusts of 18-22 kts will be possible with and
near passing -SHRA. An isolated TS cannot be ruled out with
marginal instability in place. With the bulk of the activity
expected to favor the northern half of our forecast area, wind
directions should thus tend to favor NW/N/NE components, but some
variability is likely nonetheless.

&&

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

&&

$$

DISCUSSION...12
AVIATION...BRQ

NWS BOU Office Area Forecast Discussion