207
FXUS65 KGJT 280914
AFDGJT

Area Forecast Discussion
National Weather Service Grand Junction CO
314 AM MDT Tue May 28 2024

.KEY MESSAGES...

- Conditions mainly dry and breezy, with chances for isolated to
  scattered showers and thunderstorms over the higher terrain
  each afternoon/evening throughout the week and into early next
  week.

- Aside from a brief dip to near normal temperatures Thursday,
  expect above normal warmth this week.

&&

.SHORT TERM /THROUGH WEDNESDAY/...
Issued at 313 AM MDT Tue May 28 2024

A mid-level ridge moved over the Rockies during the night, but
its axis will shift east of the Continental Divide this
afternoon as an eastern Pacific trough approaches the West
Coast. This allows modest levels of moisture in the 700 to 500
mb layer to spread north which, when combined with daytime
warming, is expected to generate another round of isolated to
low end scattered showers and thunderstorms this afternoon.
However, this activity will also include the central and
northern ranges in addition to the San Juan Mountains. In the
absence of dynamic forcing, diurnal cooling will bring an early
end to moist convection this evening. On Wednesday, flow aloft
increases from the southwest as the trough to the west sweeps
across the Great Basin driving a cold front to northeast Utah
late in the afternoon. This strengthens the pressure gradient at
the surface and aloft resulting in moderately breezy conditions,
especially across the north. Models indicated little moisture
entrained in the southwesterlies, so expect another round of
isolated/low end scattered shower/thunderstorm activity
Wednesday afternoon, mainly driven by instability.

Temperatures continue to rise today with afternoon highs on
average 5 degrees above normal with a degree or two of warming
indicated for Wednesday.

&&

.LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
Issued at 313 AM MDT Tue May 28 2024

Wednesday evening the low will be slowly tracking east across
northern Alberta with the associated trough extending southeastern
Utah and western Colorado. With the subtropical leaf of the jet
well to the south over northern Mexico and little organization
of the polar jet over the Rocky Mountains from Canada to
Arizona and New Mexico, no real activity accompanies this
trough. The region can expect generally isolated showers and
thunderstorms over the mountainous terrain mostly due to diurnal
heating and orographic lift favoring the western slopes of
rising terrain under the zonal flow in the base of the trough
with the best chances along the Divide. With the low`s slow
eastward progression, troughing remains across the northern
states through the remainder of the week keeping eastern Utah
and western Colorado under a generally dry zonal flow aloft.
This favors mostly clear skies, low humidity, and warm
temperatures, around five degrees above normal, punctuated by
afternoon scattered clouds and isolated mountain showers and
thunderstorms. Weak upper-level disturbances pass Saturday and
again Sunday with little impact to the region, but will spin up
stronger storms as they move out onto the Plains. As the low
settles in over the Hudson Bay early next week, strong ridging
starts building in over the Intermountain West bringing an
extended period of very warm and dry weather.

&&

.AVIATION /06Z TAFS THROUGH 06Z WEDNESDAY/...
Issued at 1117 PM MDT Mon May 27 2024

Expect VFR conditions with light terrain driven winds through
the TAF period. There is a slight chance for a shower near the
mountain TAF sites between about 18Z and 03Z, but chances are
too low to even mention vicinity.

&&

.GJT WATCHES/WARNINGS/ADVISORIES...

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

&&

$$

SHORT TERM...NL
LONG TERM...DB
AVIATION...DB