883
FXUS65 KGJT 311135
AFDGJT

Area Forecast Discussion
National Weather Service Grand Junction CO
535 AM MDT Sun Aug 31 2025

.KEY MESSAGES...

- Showers and thunderstorms expected this afternoon, favoring
  the San Juans, tapering off this evening.

- Temperatures surge upward today to near normal, then a few
  degrees warmer in the coming days.

- Isolated showers and storms are possible in the San Juans each
  afternoon through mid week.

&&

.SHORT TERM /THROUGH MONDAY/...
Issued at 335 AM MDT Sun Aug 31 2025

Mostly clear skies have taken over the region this morning. Drier
northwesterly flow and the building ridge continue to shunt moisture
southward. A few stray clouds linger along the west side of the
Divide, but nothing blocking a mostly starry night. That dry air is
showing up in area dewpoints with values back down in the 30`s and
low 40`s. This will come in handy for evaporative coolers this
afternoon as we warm back into the upper 80`s and 90`s in our desert
valleys. Clouds will also be hard to come by today, unless you`re in
the San Juans, where a few isolated showers will seize on the
available moisture there this afternoon. A few showers will likely
fire along the Divide northward of there in eastern Gunnison County
too. A few gusty outflows, some small hail, and brief downpours can
be expected. Outdoor recreationists will want to keep track of
lightning above treeline too. Showers will quickly taper off early
this evening at the close of afternoon heating and peak instability.

Tonight, clear skies and the lower dewpoints will usher in pleasant
conditions again across the region. Overnight lows will bottom out
at near normal. Monday afternoon, the ridge amplifies further over
the West in a vaguely blocking pattern. Temperatures will shoot up a
few degrees above normal Monday, feeling quite warm, given the
recent cool trend. Lower relative humidities will at least take a
bite out of the heat. Afternoon showers and thunderstorms continue
on the San Juans Monday. The moisture pool will continue to deplete
itself, so more of the short-lived up and down storms can be
expected. Lightning and gusty outflows will remain a threat. Quiet
high pressure conditions will quickly return Monday evening.

&&

.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
Issued at 1252 PM MDT Sat Aug 30 2025

Dry conditions return to the area and will persist through much of
the week as PWATs remain at or just below normal through the period.
Synoptically speaking, an area and ridge of high pressure will be
centered over Utah as a deep, stationary low spins off the PacNW
coast. The high won`t move much through Wednesday so our weather
will be very similar day to day. That being said, some isolated
convection is expected over the San Juans as daytime heating
releases enough instability for a brief shower or storm to fire.
Elsewhere, plenty of sunny skies with some Cu buildup over the
higher terrain and light winds are expected. During this
timeframe, deep monsoonal moisture will have been streaming up
into Arizona and Nevada thanks to the location of the ridge. For
the rest of the long term period, ensembles are suggesting an
approaching trough may force the ridge eastward allowing some of
this moisture to work into our region. While chances are low
(<30%) for convection on Thursday and Friday, coverage does
begin to increase and by Saturday chances jump to 30 to 50% for
the higher terrain for much of the CWA. This is a ways out,
however, so the usual caveats apply. Let`s wait and see how
things work out. Highs through the period will run about 3 to 5
degrees above more usual early September (it`s September
already? What happened to August?) values.

&&

.AVIATION /12Z TAFS THROUGH 12Z MONDAY/...
Issued at 532 AM MDT Sun Aug 31 2025

VFR conditions will prevail the next 24 hours beneath high
pressure. A few clouds will form on the terrain this afternoon.
Some isolated showers and thunderstorms will develop in the San
Juans and up the Divide. Included PROB30 TSRA in KTEX. These
will be pretty isolated and short-lived. Some gusty outflows,
brief MVFR ceilings, and perhaps small hail are possible.
Showers will taper by late afternoon and mostly clear skies will
close out this TAF period. Winds will remain light and variable
this afternoon with some terrain influence.

&&

.GJT WATCHES/WARNINGS/ADVISORIES...

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

&&

$$

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