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000
FXUS65 KGJT 180957
AFDGJT

Area Forecast Discussion
National Weather Service Grand Junction CO
357 AM MDT Thu Apr 18 2024

.KEY MESSAGES...

- Light snow will continue over the northern Colorado mountains
  with a couple inches at best expected above 10000 feet.

- Unsettled weather continues through the end of the week as
  additional waves brush the region.

- Temperatures will largely trend above normal through the week
  with winds gusting in the 20 to 30 mph range most afternoons.

&&

.SHORT TERM /THROUGH FRIDAY/...
Issued at 357 AM MDT Thu Apr 18 2024

Our forecast area is currently stuck between a northern stream
and southern stream with the polar and subtropical jets. To our
north, a large low pressure trough continues to gyre over the
north-central CONUS and southern Canadian border, which is
carving out a 110 kt polar jet. This jet is stretched across the
Intermountain West through Wyoming and into the Dakotas and
Minnesota. Moisture continues to stream in across the northern
and central portions of the CWA with subtle shortwaves riding
this boundary, generating some continued light scattered
orographic showers mainly affecting the northern and central
mountains. Much of the showers currently on radar seem to be
having a tough time reaching the ground as the low levels remain
dry. Expect this general pattern to continue through Friday and
into the weekend. Snowfall amounts will be minuscule though
with a couple inches at best in the northwest Colorado mountains
with some higher peaks among the central Colorado mountains
seeing a bit more but this will be above pass level with very
limited impacts if at all. So, temperatures across the north
will continue to be below normal due to the cooler air staying
north of the boundary with more clouds and showers.

To the south of this boundary, so really the central and
southern parts of the CWA, it is a different story. Warm air
advection continues as the southern sub-tropical jet tries to
push in from the south with ridging trying to take place across
Mexico into the Desert Southwest. So high temperatures will be
holding steady through the end of the week at around 10 degrees
above normal with no real change either way with this northern
stream still in place. We will see periodic clouds and sun as
mid and high level moisture traverses the area between the two
streams. The gradient also remains tighter as a result, allowing
for continued breezy conditions each afternoon with gusts in the
20s and 30s. Conditions look to remain dry in the lower
elevations through this period with really the northwest
Colorado mountains standing the best chance at any
precipitation, although amounts remain on the lighter side.

&&

.LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/...
Issued at 357 AM MDT Thu Apr 18 2024

Friday night sees the large Canadian low making its way into
the Great Lakes, with the pressure gradient over eastern Utah
and western Colorado relaxing a bit. At the same time a
shortwave trough will be moving into the southern Great Basin.
Dynamic lift and modest moisture associated with this wave will
combine with favorable orographics to keep light showers going
over mainly the northern and central Colorado mountains through
the weekend. A transient ridge will bring a break Saturday
evening before another weak wave embedded in the flow allows a
few light showers to form over the higher terrain once again
Sunday afternoon. With limited moisture and high snow levels,
snow accumulations will be less than an inch up to 2 to 4
inches at the very highest elevations, above 11000 feet,
through Monday morning. Generally zonal flow through the
midweek point will continue to keep light orographic showers in
the forecast each afternoon over the higher terrain. Ridging
builds into the West Coast on Monday, with a tight gradient
between it and the trough over the Northern Rockies leading to
another afternoon of stronger, gusty winds across eastern Utah
and western Colorado. This ridge builds in more firmly by
Tuesday, with the gradient aloft relaxing, and sticks around
through at least the midweek point. Models suggest a large
Pacific low will approach the West Coast at this point, although
they disagree substantially over almost every detail. This
feature has potential to bring some precipitation to the Western
Slope late next week.

Temperatures will remain above normal, running around 10
degrees above normal through the weekend. As the aforementioned
ridge builds in early next week, look for a gradual warming
trend allowing daytime highs to climb to as much as 15 degrees
above normal. That will put the desert valleys into the low
80s, the higher elevation valleys in the 70s, and the mountain
towns in the upper 50s to low 60s. Under these warm, dry, and
breezy conditions, caution should be used with any planned
fires, as well as being mindful of other potential spark
sources, despite fuels not yet being declared critical.
Overnight lows will also run in that 10 to 15 degrees above
normal range through the period.

&&

.AVIATION /06Z TAFS THROUGH 06Z FRIDAY/...
Issued at 1119 PM MDT Wed Apr 17 2024

VFR conditions will prevail for the next 24 hours. SCT to BKN
ceilings will linger across northwest Colorado and into the
central Colorado mountains through the period, with a few light
mountain showers possible. Winds will be generally westerly,
with afternoon gusts of 20-30 knots possible at most terminals.

&&

.GJT WATCHES/WARNINGS/ADVISORIES...

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

&&

$$

SHORT TERM...MDA
LONG TERM...BGB
AVIATION...TGJT