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000
FXUS65 KGJT 211714
AFDGJT

Area Forecast Discussion
National Weather Service Grand Junction CO
1114 AM MDT Sun Apr 21 2024

.KEY MESSAGES...

- Warm, quiet, and breezy conditions will prevail through
  Tuesday, with temperatures climbing 10-15 degrees above
  normal.

- A few weak passing waves will bring a return to mountain
  showers and storms Wednesday afternoon.

- Late week looks to bring a pattern shift to cooler and more unsettled
  weather.

&&

.SHORT TERM /THROUGH MONDAY/...
Issued at 246 AM MDT Sun Apr 21 2024

As expected, afternoon showers have tapered off and skies have
largely cleared out across eastern Utah and western Colorado. These
clear skies along with drier air aloft will allow morning low
temperatures to bottom out near to a few degrees above normal. The
morning chill won`t last long, however, as temperatures quickly
begin to climb thanks to abundant sunshine and some increased warm
air advection associated with the transient ridge passing overhead.
Highs this afternoon will run around 10 degrees above normal,
topping out in the upper 70s for the desert valleys, mid 60s to low
70s for the higher valleys, and upper 50s to low 60s for the
mountain towns. All in all, today is shaping up to be a lovely
spring day.

A trough tracking through the Northern Rockies today will flatten
the ridge overhead, with flow aloft turning more westerly. A 60-70
knot jet at the base of the trough will just brush the northern half
of the CWA beginning late tonight into tomorrow, with winds
gradually increasing. Modest moisture entrained in this flow will
move into the region tonight as well, leading to increasing cloud
cover. Between the clouds and the increasing winds, look for low
temperatures tonight to run 5-10 degrees above normal once more.
Deep mixing during the day on Monday will not only tap into the
higher winds aloft and bring afternoon gusts of 25-35 mph, but will
also tap into a pool of +6C to +8C air at 700mb. Mixing down these
already warm temperatures will help afternoon highs climb 15, and in
some spots nearly 20, degrees above normal for late April. Desert
valleys are looking at mid-80s, with higher valleys expected to see
70s, and mountain towns low to mid 60s. Dry surface air will remain
in place, with minimum RH values less than 15% across much of the
area. With warm temperatures, dry air, and breezy conditions
expected on Monday, please be mindful of campfires or any other open
burning. While fuels remain sub-critical, under these conditions it
would not take much for a small fire to get out of hand. Otherwise,
be sure to get out and enjoy this unusually nice spring weather.

&&

.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
Issued at 246 AM MDT Sun Apr 21 2024

A very warm and mainly dry forecast will be in place Tuesday and
Wednesday. There will be just enough moisture for isolated
convection in the afternoons and an outside chance of lingering
showers overnight due to passing jet dynamics across the North.
Temperatures in this early to mid week period will be running some
10 to 15 degrees above normal equating to low to mid 80s over the
desert valleys and solid 60s to near 70 in some of the mountain
towns. Unfortunately these temperatures mean deep mixing leading to
gusty afternoon winds and low humidity. If fuels are in a ready to
burn state wildfire concerns will be elevated. The latter part of
the forecast brings a lot more uncertainty though the big picture is
cooler and wetter conditions will be arriving to end out the week
and likely linger well into next week according to the latest CPC 1-
2 week outlooks. This will be good news for the snow pack in several
ways. We will melt some and then slow it down and then add some back
to the high elevations. Taking a little here and a little there is
good for keeping river levels in check and minimizing flooding
concerns. The first storm looks to arrive by Thursday though cluster
ensembles of what time Thursday is not quite clear yet. We then
continue to cycle low pressure systems though a general trough
pattern in the West which will eject somewhere across the Rockies as
they head into Plains. The strongest of these are just outside this
forecast but models fairly clear this happens to end out the weekend
and bring some interesting weather from the Great Basin to the Great
Plains into early next week.

&&

.AVIATION /18Z TAFS THROUGH 18Z MONDAY/...
Issued at 1112 AM MDT Sun Apr 21 2024

A few high clouds will move overhead today. Afternoon gusts up
to 20 kts are possible, especially for KASE and KEGE. Outside of
that, VFR conditions remain in place through tomorrow.

&&

.GJT WATCHES/WARNINGS/ADVISORIES...

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

&&

$$

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