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000
FXUS65 KGJT 220904
AFDGJT

Area Forecast Discussion
National Weather Service Grand Junction CO
304 AM MDT Mon Apr 22 2024

.KEY MESSAGES...

- Much above normal temperatures and breezy conditions the next
  few afternoons with bring elevated fire weather concerns.

- Unsettled and cooler conditions arrive Thursday onward, with
  precipitation chances becoming more widespread by the weekend,
  as a series of storms move through.

&&

.SHORT TERM /THROUGH TUESDAY/...
Issued at 304 AM MDT Mon Apr 22 2024

Upstream split flow along the Western CONUS coastline is merging
downstream over the Northern Great Basin/Central Rockies. This
zone of confluence will once again be the focus for
precipitation over the next 24 to 36 hours besides what ever isolated
mountain convection develops. The stronger system is moving
through the northern stream as expected and will move through
the Canadian Prairies to the Western Great Lakes region today
through tonight. The passage of this system looks to drop an
very weak and ill defined surface front across our northern
border today where it lingers overnight before lifting back
North tomorrow. The bulk of more focused forcing for ascent
will be coming from mid level frontogenesis tonight near the
Highway 40 corridor as the southern stream ridge builds in and
tightens the thermal gradient up north. Isentropic upglide over
the stalled front...helps connect lower level forcing to this
mid level circulation which just happens to be in a plume of
higher PWAT caught in the confluent flow. Now this all sounds
dramatic but in reality there should just be a narrow band of
nocturnal showers over our northern CWA through sunrise before
things settle down a bit. This also looks to be rather low QPF
event to go along with the limited coverage. As the ridge bulges
northward on Tuesday the forcing also looks to lift back
northward. More of a concern will be the hot and windy
conditions developing in the high mixed atmosphere under this
ridge. Afternoon highs will be some 10 to 15 degree above normal
the next few days leading to afternoon humidity in the lower
teens to single digits in the desert and lower valleys. Gusty
winds and low humidity means elevated fire danger and if fuels
were available critical fire weather conditions. Outdoor burning
is not recommended the next several days as windy and dry
conditions remain in place until late week when more significant
moisture arrives.

&&

.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
Issued at 304 AM MDT Mon Apr 22 2024

Aside from a few stubborn mountain showers, Tuesday night will be
fairly quiet across eastern Utah and western Colorado with high
pressure still in control. Southwest flow aloft will be gradually
strengthening through the day Wednesday as the next Pacific trough
moves onto the West Coast. This will begin pumping increasing
moisture into the region over the course of day Wednesday, with
increasing cloud cover and maybe a few mountain showers and storms.
Wednesday is shaping up to be the last warm, breezy, and quiet day
for the foreseeable future, as by Thursday unsettled and cooler
conditions take control.

Thursday morning will see a cutoff low at the base of the
approaching trough located over the California/Arizona/Nevada border
and poised to move into the Four Corners region by the end of the
day. This will bring scattered to widespread shower activity, with
rain in the valleys and snow generally above 10000 feet, and
overcast skies that will work to keep temperatures 5-10 degrees
cooler than at the same time on Wednesday. A break in shower
activity may come about on Friday morning as this first wave ejects
into the plains and a transient ridge moves through briefly, but a
second wave is close on its heels, bringing an upturn in activity
during the afternoon and evening hours Friday. Models are indicating
this second wave will be a bit stronger and a bit slower moving,
keeping widespread rain and snow showers over eastern Utah and
western Colorado all the way into Sunday. This second wave will also
be bringing some significantly colder air into the region, with snow
levels lowering to between 9000 and 9500 feet. Even this far out,
model guidance is hinting at some substantial (for late spring)
mountain snow accumulations with this second wave Friday through
Sunday. Models do seem to agree on the overall evolution of the
pattern, although discrepancies in timing remain at this point.
These should clear up in the coming days. Late Sunday into Monday
there is some indication that a more substantial ridge will move in
and bring a period of quieter weather, but another Pacific storm is
waiting in the wings for next week. So be sure to enjoy the nice
weather while you can.

Temperatures will start out warm for Wednesday, with highs running
around 15 degrees above normal. Increasing clouds and showers
Thursday will initiate a pronounced cooling trend for the end of the
week and into the weekend. Highs on Thursday will run 5-10 degrees
above normal, by Friday look for near-normal values, and by Saturday
current guidance has temperatures running around 5 degrees below
normal! Overnight lows will also exhibit something of a cooling
trend, but the increased clouds and moisture will temper that
somewhat, so look for lows starting out around 10 degrees above
normal Wednesday night and cooling to near normal by Saturday
night.&&

.AVIATION /06Z TAFS THROUGH 06Z TUESDAY/...
Issued at 1110 PM MDT Sun Apr 21 2024

VFR conditions under light winds will hold through the mid
morning hours. Winds will increase with gusts of 25 to 35 mph
through the late morning and early afternoon hours at most TAF
sites on Monday...however cigs should be above ILS levels.

&&

.GJT WATCHES/WARNINGS/ADVISORIES...

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

&&

$$

SHORT TERM...15
LONG TERM...BGB
AVIATION...TGJT