612
FXUS65 KGJT 270920
AFDGJT

Area Forecast Discussion
National Weather Service Grand Junction CO
320 AM MDT Mon May 27 2024

.KEY MESSAGES...

- Isolated showers and thunderstorms are possible over the San
  Juan Mountains this afternoon with mostly dry and warmer
  conditions area wide.

- Drier and warmer conditions expected this week with
  temperatures warming to five to ten degrees above normal by
  mid week.

- Precipitation chances remain low through most of the week with
  any storm activity favoring the high terrain during the
  afternoon period.

&&

.SHORT TERM /THROUGH TUESDAY/...
Issued at 319 AM MDT Mon May 27 2024

A mid-level high pressure ridge develops over the Rockies today
ahead of a trough over the eastern Pacific. Modest moisture in
the 700 to 500 mb layer combines with jet divergence to generate
isolated to low end scattered showers and thunderstorms over
the San Juan Mountains with lesser chances over the central
Colorado mountains. Driven largely by instability resulting from
daytime heating, this activity should diminish by early evening.
As the eastern Pacific trough approaches the West Coast on
Tuesday the ridge axis is forced east of the Continental Divide
by late afternoon. The resultant shift in flow aloft to the
southwest carries moisture northward and as a result, afternoon
moist convection spreads into the central and northern Colorado
mountains and the eastern Uinta Mountains Tuesday afternoon.

The warming trend continues early this week with readings near
or a couple of degrees warmer than normal today with around 5
degrees of additional warming on Tuesday.

&&

.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
Issued at 319 AM MDT Mon May 27 2024

The upstream trough will continue to push onshore Tuesday night
before swinging through the Intermountain West on Wednesday.
Southwest flow will deepen across eastern Utah and western Colorado
in response with Wednesday`s high temperatures jumping to 5 to 10
degrees above normal. In fact, the first 90 degree day looks
possible for some of the lower valleys across southeast and east-
central Utah as well as the Grand Valley. Of course, this is subject
to change and will be dependent on how far south the approaching
trough dives. At the moment, dry weather looks to prevail for most
areas through the midweek point with just some passing clouds into
Thursday. The higher terrain along the Divide could some isolated to
scattered showers and thunderstorms both Wednesday and Thursday
afternoons as the trough continues to lift northeast into
Saskatchewan. A strong ridge of high pressure amplified over Hudson
Bay will keep the low stalled over central Canada on Friday
resulting in persistent zonal flow across the Western Slope. A
secondary embedded wave looks to push through the flow late in the
week, resulting in slightly better shower coverage along the higher
terrain. This will also knock temperatures back down closer to the
normal for this time of year but overnight lows will continue to
trend slightly above normal through the period. Drier weather is
projected to return for the weekend.

&&

.AVIATION /06Z TAFS THROUGH 06Z TUESDAY/...
Issued at 1114 PM MDT Sun May 26 2024

Look for light, terrain driven winds and VFR conditions over the
area through the next 24 hours as a ridge of high pressure
builds over the region.

&&

.GJT WATCHES/WARNINGS/ADVISORIES...

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

&&

$$

SHORT TERM...NL
LONG TERM...MMS
AVIATION...TGJT