649
FXUS65 KGJT 291750
AFDGJT

Area Forecast Discussion
National Weather Service Grand Junction CO
1150 AM MDT Wed May 29 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 THURSDAY/...
Issued at 347 AM MDT Wed May 29 2024

With the ridge pushed out onto the Plains and the trough moving
ashore in the Pacific Northwest, the southwesterly flow aloft over
eastern Utah and Western Colorado is advecting a drier airmass above
550 mb into the region spelling a down turn in convective activity
this afternoon. Will still have isolated to scattered showers and
thunderstorms favoring the terrain through peak diurnal heating with
the warmest high temperatures for the week at five to ten degrees
above normal for the end of May, a little warmer than yesterday.
Look for increased winds at 20 mph gusting 30 mph this afternoon
with the tightening pressure gradient ahead of a cool front pushing
in from the northwest. Shower activity will continue into the
evening in the northern mountains as a cool front moves through.
There isn`t much moisture entrained with this front, limiting
convection in spite of the frontal dynamics. The primary threats
will be gusty outflow winds and occasional lightning. The front will
move to the southeast through the region overnight possibly kicking
off an isolated shower and dropping temperatures Thursday by about
five degrees. With the drier air in place, Thursday will see yet a
further down-tick in convective activity across the region with only
isolated showers and thunderstorms mostly along the Continental
Divide.

&&

.LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/...
Issued at 347 AM MDT Wed May 29 2024

As noted in previous discussions, there`s been a noticeable poleward
shift in the polar jet according to latest models. As a result, flow
aloft has weakened, and the influence of long wave energy appeared
markedly diminished over the forecast area in the long term. As
little moisture was indicated to move into the area with flow
largely zonal, moist convection will be the product of diurnal
warming and the resultant instability it brings. Aside from
Saturday, afternoon and early evening thunderstorms are expected to
be isolated in coverage and confined mainly to the mountains of the
Continental Divide. The main threat from this activity will be
strong outflow winds as the subcloud layer appeared very dry in
forecast soundings. The uptick in shower activity Saturday appeared
to be the result of easterly flow over the eastern Plains of
Colorado which drives moisture to the forecast area`s eastern
boundary. Aside from the aforementioned mountains, the remainder of
the forecast area will be dry with temperatures hovering near 5
degrees above normal on average.

&&

.AVIATION /18Z TAFS THROUGH 18Z THURSDAY/...
Issued at 1150 AM MDT Wed May 29 2024

VFR conditions should prevail over the next 24 hours. Isolated
to scattered showers and thunderstorms have developed late this
morning over the northern and central mountains and are expected
to favor the high terrain, although some drift into adjacent
valleys to the east-northeast cannot be ruled out. Gusty outflow
winds to 40 mph or greater are possible near any storms.
Confidence was high enough to include VCTS at KHDN, KASE, KEGE
and KGUC where convection is expected to continue. Otherwise,
breezy afternoon winds of 20 to 35 mph are possible at times
with partly to mostly sunny skies elsewhere. Gusty winds and
VCSH expected to accompany the frontal passage, especially
across the north this evening. Skies should clear and showers
dissipating overnight.

&&

.GJT WATCHES/WARNINGS/ADVISORIES...

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

&&

$$

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