276
FXUS65 KBOU 030937
AFDBOU

Area Forecast Discussion
National Weather Service Denver/Boulder CO
337 AM MDT Fri May 3 2024

.KEY MESSAGES...

- Isolated showers on the northeast plains tonight.

- Warmer and windy on Sunday.

- Sunday night into Monday will see a good chance of snow showers
  in the mountains. Windy and cooler over the entire area.

&&

.SHORT TERM /Through tonight/...
Issued at 336 AM MDT Fri May 3 2024

GOES-18 Mid-level Water Vapor displays showers and storms located in
Wyoming this morning. The shortwave trough axis will likely stay to
the north but our area should receive an increase in mid-level
starting late morning. Additionally, a breezy day will occur through
this evening across the region with wind gusts up to 35 mph as the
shortwave trough lifts north. 700mb temperatures reach 6-8C; this
will allow for afternoon temperatures to reach the upper 60s to
lower 70s across the urban corridor and plains. Mountains and
valleys should warm up to the mid 40s to 50s this afternoon. Weak
instability between 100-300 J/kg will likely support scattered
showers and storms this afternoon. Favorable conditions for severe
storms are mainly along the Kansas Colorado border late afternoon
and early evening. If a storm is able to develop in that
environment, expect 1 inch hail and wind gusts up to 60 mph. With
snow level roughly near 8k ft, higher elevations especially along
the Park Range could accumulate snow up to 1-4 inches through
Saturday morning.

Late afternoon, a cold front will sweep into the CWA increasing wind
gusts once more. This may produce wind gusts up to 45-50 mph. As the
cold front passes, it is possible the environment becomes too stable
to support any additional thunderstorm development. Tonight, drier
air enters our region. Low temperatures remain near normal.

&&

.LONG TERM /Saturday through Thursday/...
Issued at 336 AM MDT Fri May 3 2024

The flow aloft will become WSW on Sat as a weak sfc lee trough
develops by aftn.  This will allow for SSE low level flow to develop
across the plains. Some moisture will affect the higher terrain
by aftn with MLCAPE around 200 j/kg. As a result, there will be a
chc of aftn showers and a few tstms, especially over the higher
terrain along and south of I-70. Across the plains it will be dry
and cooler with highs in the 60`s.

By Sun, SW flow aloft will increase across the area as a storm
system moves into the Great Basin. In addition, sfc low pres will
intensify from central WY into ern CO with stg southerly flow in
the lower levels. As a result, will likely see winds gusts in the
45-55 mph range across the plains Sun aftn. As far as precip
chances, MLCAPE will rise to around 300 j/kg over portions of the
plains, however, there is a capping inversion which probably will
inhibit tstm development. Meanwhile, highs will be warmer over
most of the plains as readings rise into the 70`s. The only
exception would be over the far ern plains, where highs may stay
in the mid to upper 60s due to low level cloud cover.

For Sun night into Mon, the storm system over the Great Basin will
move quickly ENE with an intense upper level low moving into ern
WY, by Mon aftn. As the srn extent of the upper level trough
moves across nrn CO, there will be a round of snow in the mtns Sun
night into Mon morning. Across the plains, a bora type front will
move across during the day with gusty WNW winds developing by
midday. There also could be a chc of showers in the morning as a
quick shot of mid level ascent moves across. Highs across the
plains will drop back into the 60`s.

Looking ahead to Mon night into Tue, an intense storm system will be
over the nrn Plains.  This will allow for brisk WNW flow aloft
across the area.  Cross-sections, show enough moisture embedded in
the flow to bring a chc of orographic snow showers to the mtns.
Across the plains, it will be dry with gusty WNW winds continuing.

On Wed, the storm system will move slowly eastward with WNW flow
aloft remaining over the region.  Once again, there will be some
moisture embedded in the flow to bring a chc of snow showers to the
mtns.  Across the plains, it will remain dry and windy with highs
remaining in the 60`s.

By Thu, the flow aloft will become more NW as a shot of cooler air
moves into the area behind a front.  In addition, there may be a
disturbance embedded in the flow which could bring a chc of precip
to the region as well.

&&

.AVIATION /06Z TAFS through 06Z Saturday/...
Issued at 1141 PM MDT Thu May 2 2024

VFR conditions continue for the TAF period. Weak rain showers will
stay east of all terminals keeping southeast flow at all sites.
Winds increase between 14-17kts and shift southeasterly by mid
afternoon. Gusts up to 22-28kts could occur. It is possible just
before the front arrives, scattered showers and storms develop
northeast of all terminals. Outflow from these showers could lead
to stronger wind gusts up to 30-35kts and variable wind direction.

A cold front should arrive sometime between 23-01Z thus
increasing wind briefly between 20-24kts. By 03-05Z, winds will
decrease but struggle to turn back into drainage. Expect
northeasterly flow late Friday night through Saturday morning.

&&

.FIRE WEATHER...
Issued at 256 AM MDT Fri May 3 2024

It will be windy over the plains Sunday through Tuesday. Humidity
levels will gradually drop from Monday into Tuesday. However,
recent rainfall combined with greening up of vegetation could
reduce fire danger across portions of the plains. At the time,
the most likely area for increasing fire danger would be over
southern Lincoln county.

&&

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

&&

$$

SHORT TERM...AD
LONG TERM...RPK
AVIATION...AD
FIRE WEATHER...RPK