679
FXUS65 KGJT 281745
AFDGJT

Area Forecast Discussion
National Weather Service Grand Junction CO
1145 AM MDT Sun Apr 28 2024

.KEY MESSAGES...

- A disturbance will move over the area today bringing some
  showers and a few storms this afternoon and evening.

- High temperatures start warming up day by day.

- The next chance for more widespread precipitation looks to
  occur Wednesday afternoon through Thursday afternoon.

&&

.UPDATE...
Issued at 614 AM MDT Sun Apr 28 2024

Some light snow will continue over the mountains this morning
but any snow that will fall on roads or pavements will quickly
melt. With impacts decreasing, allowed all advisories to expire.

&&

.SHORT TERM /THROUGH MONDAY/...
Issued at 254 AM MDT Sun Apr 28 2024

The system that brought all the snow and rain yesterday has
shifted to the Plains where severe weather is ongoing. Some
light snow continues at the highest elevations of the CO
mountains though it looks to have really died down for the
Uintas. Went ahead and cancelled the advisory there but will
keep them going through 12Z for the CO mountains. The next
question for the overnight hours will be fog. Dewpoint spreads
for many locations are fairly close together and local obs are
showing low broken to overcast skies so some fog is very likely.
Will be interesting to see if we get any sunrise surprises this
morning. Sunday will bring one more day of unsettled weather as
a shortwave drops in from the northwest. This shortwave will
work on cold air aloft and with plenty of midlevel instability
across the area, another round of showers and storms will be
possible this afternoon and evening. Another inch or two of snow
is also possible along the higher terrain of the Continental
Divide. Variable cloudiness will be the rule with more cloudy
skies over and around the mountains with clearing skies for
eastern UT and far western CO through the day. With less precip
and cloud cover, high temps should rebound about 4 to 8 degrees
from yesterday.

Zonal flow sets up across the CWA Monday as the next system
moves across the PacNW. Favorable windflow may allow some
showers to form over the northern mountains during the day but
that should be about it. Heading towards the late
afternoon/evening hours, said system to our north will drag a
cold front far enough south that it could bring some showers to
our northern valleys/mountains. Elsewhere, dry conditions
expected with some of the usual afternoon gusts of 20 to 25 mph
with higher gusts up north. Clouds will also increase in the
afternoon in response to the approaching front but they should
remain partly cloudy...with plenty of sun south of the San
Juans. The warmup continues as highs jump another 4 to 8
degrees.

&&

.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
Issued at 254 AM MDT Sun Apr 28 2024

A broad area of cyclonic flow stretching from the PACNW all the way
to the Northern Plains will continue to play a part in this week`s
extended forecast. Kicking off the period Monday night is a pocket
of northeast Pacific moisture working through the Intermountain West
on the shoulders of a strong jet streak digging out a trough into
the north of the Great Basin. As this feature works east, it is
expected to clip our northern Mountains early Tuesday with enough
moisture to drop additional snowfall on the Flat Tops, Elk Heads,
and Park Range. This clipper will be an afterthought though, as most
of its moisture is gone before your second cup of coffee Tuesday
morning. Temperature advection will remain neutral to warm
Tuesday afternoon and afternoon highs will rebound into the 70`s
for our warm desert valleys and perhaps 80`s for our southeast
Utah deserts. Reinforcements to the low pressure occupying the
Intermountain West up north arrive Wednesday, as another pulse
of the jet digs deeper into the Great Basin. Gradients tighten
and southwesterly winds kick up Wednesday afternoon in front of
a pending cold front. Presently, some additional moisture
wrapping around the low to our north will generate some cloud
cover and a shower or two across our northern counties Wednesday
afternoon. This will likely check afternoon highs down a bit
and hopefully take a bite out of fire weather concerns in the
gusty regime ahead of the incoming front. The passing front
early Thursday morning will send us back below climatology for
temperatures Thursday through Friday morning. It will also bring
some more valley rain and mountain snow to much of the northern
half of the CWA. Post-frontal showers and thunderstorms will
likely present themselves Thursday afternoon before we scour out
the remaining moisture late Thursday night. Model solutions are
not in lockstep with the depth of the trough on this late week
system. There is a chance this system fails to dig south enough
for any impacts beyond far north Colorado. Mean flow flattens
out Friday and Saturday ahead of a weak transitory ridge models
are trying to paint over the Great Basin. This looks good enough
for another warm up next weekend. Still time to rework this
forecast, given spring time model discontinuities.

&&

.AVIATION /18Z TAFS THROUGH 18Z MONDAY/...
Issued at 1145 AM MDT Sun Apr 28 2024

Just as this morning`s low clouds and fog started clearing out,
daytime heating and a weak wave moving overhead have allowed
clouds to start filling back in. Ceilings will hover between
VFR/MVFR across most mountain terminals this afternoon with ILS
breakpoints being reached at times as well. Scattered showers
and a few storms will be around but will start to diminish after
the sun sets. Any shower or storm can produce erratic and gusty
winds. More widespread VFR returns late this evening with skies
becoming partly cloudy overnight. Quiet weather then prevails
through the day on Monday with light, terrain driven winds.

&&

.GJT WATCHES/WARNINGS/ADVISORIES...

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

&&

$$

UPDATE...TGR
SHORT TERM...TGR
LONG TERM...LTB
AVIATION...TGJT