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000
FXUS65 KGJT 212322
AFDGJT

Area Forecast Discussion
National Weather Service Grand Junction CO
522 PM MDT Sun Apr 21 2024

.KEY MESSAGES...

- Warm and breezy conditions will lead to near critical fire
  weather conditions Monday with low relative humidities and
  winds gusts of 25-35 mph across much of the region.

- Temperatures will remain around 15-20 degrees above
  climatology through midweek, before another disturbance cools
  things off toward the end of the week.

- Unsettled and cooler conditions are expected Thursday onward,
  with precipitation chances becoming more widespread, as a
  series of storms move through.

&&

.SHORT TERM /THROUGH MONDAY NIGHT/...
Issued at 236 PM MDT Sun Apr 21 2024

A flattened ridge of high pressure sits over the Great Basin this
afternoon southward of an area of low pressure tracking over the
northern Rockies. This dirty ridge will see a few parcels of
moisture trickle across the northern portion of the CWA today and
tomorrow. A stray shower on the mountains up north can`t be ruled
out, but mostly just some scattered cloud cover on the terrain is
the best we`ll do. Afternoon heating will continue to be productive
for winds, as temperatures climb well above normal under the
amplifying ridge. High temperatures on Monday will be around 15
degrees over climatology. Low relative humidity values and gusty
winds(25-35 mph) will lead to near critical fire weather conditions
Monday afternoon in portions of eastern Utah and western Colorado.
Fuels remain sub-critical and thus Red Flags weren`t considered at
this time. Overnight lows tonight and Monday night will remain warm
as well. A pulse of upper level moisture turns up Monday and likely
brings up dewpoints, thereby keeping temperatures warmer Tuesday
morning and adding additional cloud cover southward in the CWA.

&&

.LONG TERM /TUESDAY THROUGH SUNDAY/...
Issued at 236 PM MDT Sun Apr 21 2024

Weak ridging tries to build into the CWA Tuesday and as this occurs
an increase in moisture also occurs. Weak disturbances will ride
through the mean flow, and despite the ridging, models continue to
highlight some light precip along the UT/CO border and Continental
Divide. The NBM is putting a 30 to 50% chance of some rain showers
and slight chance storms over those areas and this seems reasonable.
Nothing widespread, mind you, much more isolated in nature. Similar
conditions are possible Wednesday though coverage does look to be a
bit less, for those same areas. While all this occurs, a Pacific
trough will be coming ashore and as it moves eastward, will carve
out a low at the base of the trough by Thursday morning. Ahead of
this feature, winds will increase thanks to a tightening surface
pressure gradient and clouds will increase as moisture continues to
stream in from the southwest. Despite the cloud cover, highs will
remain above normal for this time of year though will be around 5
degrees cooler than those seen on Wednesday. As the trough moves
across our region during the day Thursday, isolated to scattered
showers will occur with a few storms possible as well. Snow levels
will setup around 10K feet and with it being almost May, any snow
that falls on road surfaces will very quickly melt.

By Friday morning, the trough will have shifted to the Plains but we
will continue to see unsettled weather as a shortwave moves through.
This wave will bring another round of rain and mountain snow through
Friday evening. This wave will favor areas north of I-70 and
portions of the central mountains. Not done yet as the next deep
trough drops down from the PacNW and brings another round of precip
to the region starting Saturday morning and possibly persisting
through the weekend. Mountain snow and valley rain continues. As
always, this far out we`ll see some changes with regards to how this
pattern evolves but models remain consistent that a prolonged period
of unsettled weather will start Thursday and continue through the
weekend. Enjoy the beginning of the week as the end will be
drastically different.

&&

.AVIATION /00Z TAFS THROUGH 00Z TUESDAY/...
Issued at 522 PM MDT Sun Apr 21 2024

VFR conditions will prevail for the next 24 hours with
occasional mid and high level clouds passing overhead. Gusty
winds will diminish this evening and become light and terrain
driven through Monday morning. Winds increase again Monday
afternoon with gusts of 25 to 35 kts likely for most terminals.

&&

.GJT WATCHES/WARNINGS/ADVISORIES...

CO...None.
UT...None.

&&

$$

SHORT TERM...LTB
LONG TERM...TGR
AVIATION...TGJT