273
FXUS65 KGJT 070546
AFDGJT

Area Forecast Discussion
National Weather Service Grand Junction CO
1146 PM MDT Tue May 6 2025

.KEY MESSAGES...

- Another active weather day is on tap today with mountain snow
  and afternoon storms providing another opportunity for some
  much-needed precipitation.

- Unsettled weather with warming temperatures highlight the
  forecast Wednesday into the weekend.

&&

.SHORT TERM /THROUGH WEDNESDAY NIGHT/...
Issued at 211 PM MDT Tue May 6 2025

Low pressure system is currently located over eastern New
Mexico and clockwise flow is giving us winds generally out of
the east to northeast aloft. A few locations are gusting 30-45
mph and that may continue through the day. This system is
advecting highly anamolous moisture into the Divide and
providing lift for portions of the area. The result is
precipitation making it over the Divide into our area especially
the southern San Juan and foothills as well as the Sawatch.
Daytime heating has forced snow levels to about 8-9 kft
impacting Monarch and Wolf Creek passes. Instability is
increasing on the edge of the cirrus shield, which should
support showers and storms this afternoon and evening.
Unfortunately, the models have not handled this well so precip
chances may be overdone. Pockets of light to moderate rain,
small hail and gusty winds are possible with the strongest
cells. This shower activity will move westward and exit the area
around midnight. Continues dry out tonight as the low lifts out
over the Southern Plains. Skies will clear and places with
recent rain could see fog overnight. Moisture lingers tomorrow
although there will not be much lift. Therefore heating tomorrow
afternoon should result in orographic showers and storms over
most of the mountains. While some of these showers could leave
the terrain a bulk of the QPF is in the mountains.

&&

.LONG TERM /THURSDAY THROUGH TUESDAY/...
Issued at 211 PM MDT Tue May 6 2025

By Thursday, models are in good agreement with the low well to
the east over Missouri and a high over Minnesota in a Rex block
pattern that will slow the progress of the next system, a deep
cold low descending out of the Gulf of Alaska that won`t impact
the West Coast until early next week. Subsidence under the
ridging that sets up over eastern Utah and Western Colorado will
clear out the skies overnight allowing strong diurnal heating
to warm temperatures each day. Look for temperatures about five
degrees above normal Thursday, and about ten degrees above
normal Friday into early next week. With no strong flow to sweep
the moisture out of the region during this period, expect
generally unsettled weather each day with afternoon showers and
thunderstorms developing over the mountains from the residual
moisture and diurnal heating, and a few moving off the terrain
into the lower valleys. This pattern should hold through the
weekend into early next week.

The deterministic models have the low to the east shifting into the
Midwest and Appalachia, with ridging setting up across the
Plains States and the next low pressure system to the west
moving in over the West Coast to set up an Omega blocking
pattern across the CONUS. The ensembles handle the synoptic
pattern a bit differently with the Rex Block slowly shifting
east over Appalachia and the low pressure system to the west
stalling out over the West Coast and Great Basin. Either of
these scenarios will generally have the same outcome for eastern
Utah and Western Colorado with the low stalled to the west
pulling significant moisture east and north off the eastern
Pacific and Gulf of California in a monsoon-like pattern. Is
this the start of the monsoon? NO! To really get monsoonal
moisture, the Gulf of California needs to warm into the 80`s to
support the deep monsoonal moisture, and its currently quite
cool in the low 60`s. But that being said, this pattern will
tend to keep cloudy, cool and unsettled weather with diurnally
driven afternoon showers and thunderstorms in the forecast
through next week and for the foreseeable future.

&&

.AVIATION /06Z TAFS THROUGH 06Z THURSDAY/...
Issued at 1140 PM MDT Tue May 6 2025

Expect partly sunny skies for Wednesday with scattered afternoon
convection developing over the high terrain. Brief visibility
and ceiling reductions are likely if showers move over a
terminal.

&&

.GJT WATCHES/WARNINGS/ADVISORIES...

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

&&

$$

SHORT TERM...KJS
LONG TERM...DB
AVIATION...TGJT