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000
FXUS65 KBOU 220246
AFDBOU

Area Forecast Discussion
National Weather Service Denver/Boulder CO
846 PM MDT Sun Apr 21 2024

.KEY MESSAGES...

- Warmer on Monday with a slight chance of afternoon showers
  and isolated thunderstorms.

- Potential for stormier weather pattern starting late Thursday
  into next weekend.

&&

.UPDATE...
Issued at 845 PM MDT Sun Apr 21 2024

Minimal updates this evening. Made minor refreshments to the sky
grids to better reflect current stream of high clouds pushing into
northeast Colorado.

&&

.SHORT TERM /Through Monday/...
Issued at 221 PM MDT Sun Apr 21 2024

After multiple days of continuous cloud cover, skies have finally
cleared out this aftn. Tonight, mid and high level moisture will
move in from the NW with some mtn wave cloud cover overnight. Will
see gusty winds overnight in the normal windy areas but cross
barrier flow is only in the 30-35 kt range.

On Mon, WNW flow aloft will remain over the area with additional mid
level moisture embedded in the flow.  Lapse rates by aftn will be in
the 8-9 c/km range with MLCAPE up to 200 j/kg.  Overall, expect some
widely sct high based showers and isold tstms in the aftn.  This
activity will produce mainly wind with very little rainfall as
lower levels will remain rather dry.  Outside of the showers, it will
be windy across the higher terrain but speeds will stay below high
wind criteria.

Highs on Mon will be much warmer as 850-700 mb temps rise 8-10
degrees from today`s levels. This would lead to highs in the 70s
across nern CO.

&&

.LONG TERM /Monday night through Sunday/...
Issued at 221 PM MDT Sun Apr 21 2024

West-northwest flow aloft to prevail Monday night and Tuesday. An
upper level low will track southeast across the Northern Plains
staying well northeast Colorado. A cold front associated with this
system pushes south through eastern Colorado Monday night. This
will usher in cooler temperatures for Tuesday. Expect some stratus
clouds Tuesday morning, which will slow warming. Highs look to be
in the upper 50s to lower 60s Tuesday. Scattered showers and few
thunderstorms will be possible over the higher terrain where it
will be unstable. A few could survive onto the plains, late
Tuesday afternoon and evening. If any convection makes it onto the
plains, it is expected to be weak.

Temperatures warm back up for Wednesday as an upper level ridge
moves over the state. Highs are expected to reach the mid to upper
70s over northeast Colorado. Can`t rule out a stray shower or
storm over far northern Colorado Wednesday afternoon/evening.
However, overall dry and warm conditions are expected. The warm
temperatures are expected to continue into Thursday as the ridge
shifts east of Colorado. On the heels of the ridge will be a quick
moving upper level trough. This will bring a better chance for
showers and thunderstorms Thursday and Thursday night.

Weak ridging will replace the trough for Friday, though models
are hinting there may be enough moisture embedded in the westerly
flow aloft to produce rain/snow showers over the mountains. Models
also hinting at a few showers late in the day across the lower
elevations, though any activity should be weak.

For next weekend, a large upper level low/trough will be across
the western half of the country. With this system nearly a week
away, not surprising there are differences on the timing,
placement, and strength. Good chance temperatures will trend
cooler. Precipitation amounts (1-2 inches) are possible if this
system takes the right track. This system looks to be warmer,
which should keep precipitation mostly to all rain across the
lower elevations.

&&

.AVIATION /00Z TAFS through 00Z Monday/...
Issued at 528 PM MDT Sun Apr 21 2024

VFR conditions will prevail for all terminals through the TAF
period. Expect increasing high clouds this evening at/above FL180,
persisting through the forecast period.

Current southeast winds should turn to southerly drainage within
the next 1-3 hours for KDEN/KAPA, with sustained speeds likely
remaining above 10 kts and with occasional gusts near 20 kts
possible in the evening before relaxing some during the early
morning hours.

Winds will shift more southwesterly Monday morning, before
transitioning to WNW flow near midday. Afternoon gusts should
exceed 20-25 kts for all areas. SCT-BKN mid-level clouds at/above
080 appear likely, along with isolated high-based showers/virga
over the low elevations in the afternoon. Precipitation isn`t
favored, but virga could produce brief higher gusts closer to 30
kts at times.

&&

.FIRE WEATHER...
Issued at 221 PM MDT Sun Apr 21 2024

Elevated fire conditions will be in place over southern Lincoln
county Monday afternoon due to low humidity and gusty west
to southwest winds.

&&

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

&&

$$

UPDATE...Rodriguez
SHORT TERM...RPK
LONG TERM...Meier
AVIATION...Rodriguez
FIRE WEATHER...RPK