448
FXUS65 KBOU 221132
AFDBOU

Area Forecast Discussion
National Weather Service Denver/Boulder CO
532 AM MDT Wed May 22 2024

.KEY MESSAGES...

- Warmer and drier today and Thursday, with elevated to critical
  fire weather conditions possible by Thursday.

- Scattered showers and storms each afternoon from Friday into the
  weekend.

&&

.SHORT TERM /Through tonight/...
Issued at 417 AM MDT Wed May 22 2024

Satellite this morning shows a much quieter picture across the
state compared to the last couple of days, with the shortwave
trough axis now off to the north and east of our forecast area.
There was a briefly amplified mountain wave which produced some
50-60mph gusts over the higher elevations of Boulder/Gilpin
counties earlier that was aided by the subsidence immediately
behind the departing s/w, but wind gusts have diminished
significantly in the last hour or two. Across the plains, most
locations in the Frost Advisory have dropped into the mid 30s with
a few sites closer to freezing... and that headline will remain in
effect through the mid-morning.

The rest of the day should be quiet as much drier air remains over
the region. Temperatures should rebound nicely compared to
yesterday, with highs back to near normal values (low/mid 70s) in
the Denver metro. Can`t rule out an isolated shower or storm
across the far eastern plains later where guidance shows just
enough moisture and meager CAPE.

&&

.LONG TERM /Thursday through Tuesday/...
Issued at 417 AM MDT Wed May 22 2024

An somewhat more active weather pattern is expected through the
extended forecast period, however, it will kick off with a brief
warm and dry period on Thursday. A mostly zonal flow aloft will
turn slightly southwesterly over Colorado as an upper level low
traverses to the north. Guidance continues to agree on the track
and intensity of the disturbance as well as its main forcings
staying north of the forecast area. 700 mb temperatures look to be
roughly four degrees warmer for Thursday than that seen on
Wednesday, which will assist in bringing maximum temperatures up
to the high 70s or even low 80s across the plains. The foothills
will be in the mid to high 60s, and the mountains will be high 50s
to low 60s. Colorado will be on the west side of a dryline, and
with increasing winds and southwesterly surface flow, it is
possible for elevated/critical fire weather conditions to develop
over portions of the plains, Palmer Divide, and South Park
Thursday afternoon. For Thursday night, a cold front will pass
through northeastern Colorado that will help subdue any of the
elevated fire weather concerns for Friday.

Friday will be roughly 10 degrees cooler than Thursday behind the
cold frontal passage. An approaching shortwave trough to the west
will help increase moisture and there will be a chance for daily
afternoon isolated to scattered showers and thunderstorms through
the weekend and even some light snow showers for the mountains.
Solutions begin to diverge slightly with regards to the next upper
level low dropping into the PNW Saturday night that could impact
our forecast area, but there is better agreement that a ridging
pattern will build over the western CONUS in the Monday/Tuesday
timeframe bringing warmer and drier conditions.

&&

.AVIATION /12Z TAFS through 12Z Thursday/...
Issued at 530 AM MDT Wed May 22 2024

VFR through the TAF period. Drainage winds are expected to turn
more to the southeast later this morning into the afternoon as a
Denver Cyclone develops. As the cyclone forms and drifts
northeastward, the terminals may see a brief shift to a
northwesterly wind later this afternoon. Still not great
confidence in the timing of any wind shift or the predominant
direction the winds will turn to, but previous TAF captured the
general thinking. Drainage winds are expected again tonight.

&&

.FIRE WEATHER...
Issued at 417 AM MDT Wed May 22 2024

Warm and dry conditions are expected for Thursday that will bring
elevated to critical fire weather conditions to portions of the
urban corridor, Palmer Divide, and South Park. With recent
precipitation and greenup occurring in spots throughout these
locations, fuel status will play an important role in whether
or not Fire Weather Watches/Red Flag Warnings would be necessary.
As of now, relative humidities are expected to drop to below 15%
as winds increase through the morning and afternoon, surpassing
Red Flag Warning criteria in some locations. Updated fuel
conditions will be helpful today to get a better idea on whether
any highlights will be needed.

&&

.BOU WATCHES/WARNINGS/ADVISORIES...
Frost Advisory until 8 AM MDT this morning for COZ038-041>047-
049.

&&

$$

SHORT TERM...Hiris
LONG TERM...Bonner
AVIATION...Hiris
FIRE WEATHER...Bonner