Grand Junction, Colorado 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

698
FXUS65 KGJT 250529
AFDGJT

Area Forecast Discussion
National Weather Service Grand Junction CO
1129 PM MDT Thu Apr 24 2025

.KEY MESSAGES...

- A weak disturbance will bring scattered showers and a few
  thunderstorms to northeast Utah and northwest Colorado this
  afternoon through early this evening.

- Critical fire weather conditions featuring warmer than normal
  temperatures, low relative humidity and strong winds are
  expected to develop Friday, potentially redeveloping each day
  this weekend.

- Red Flag Warnings and Fire Weather Watches are in place for
  portions of central and southwest Colorado this weekend.

- A cooler, showery pattern will follow this weekend`s
  disturbance bringing higher relative humidities and lower
  temperatures across the region.

&&

.SHORT TERM /THROUGH FRIDAY NIGHT/...
Issued at 333 PM MDT Thu Apr 24 2025

Modest moisture in conjunction with a low amplitude mid-level
short wave trough was responsible for scattered showers and
embedded thunderstorms over northeast Utah and northwest
Colorado. Elsewhere, skies were mostly sunny to partly cloudy
and unusually mild.

Subsidence settles over the area by 00Z/Fri, so showers will
dissipate fairly quickly this evening. High clouds will stream
overhead during the night while cumulus/altocumulus decrease
with diurnal cooling. Overnight lows are expected to continue
to run above normal in the lingering mild airmass over the
region.

Flow continues out of the southwest and increases on Friday
ahead of a closed low circulation drifting southward off the
California coast. Strengthening winds aloft mix down from late
Friday morning through Friday evening resulting in breezy
conditions. This combined with unusual warmth and low relative
humidity will lead to critical fire weather conditions. A Red
Flag Warning is in effect from noon until 8 PM for portions of
west-central and southwest Colorado. Meanwhile, mostly sunny
skies combined with mixing will allow above normal temperatures
to continue for much of the region. Modest moisture over the
northern Colorado mountains along the Divide may be sufficient
for isolated/widely scattered showers/thunderstorms.

Showers die off with diurnal cooling, while at the surface
winds relax and shift to a downslope/downvalley regime in the
evening. A broad cirrus shield over the area in the evening
moves off to the northeast overnight. Despite clearing,
overnight lows will be unusually mild for this time of year.

&&

.LONG TERM /SATURDAY THROUGH THURSDAY/...
Issued at 333 PM MDT Thu Apr 24 2025

Saturday afternoon, the approaching closed low will be situated
over central California, thus maintaining a warm air advecting
southwesterly flow over the CWA. This continues to fuel the
heightened fire hazard we are seeing both throughout the short
term and this early period of the long term forecast. As a
result, a Fire Weather Watch is in effect from noon through 8pm
on Saturday. As the low pushes further into the Great Basin,
surface pressure gradients tighten across Utah and Colorado. As
a result, strong winds are expected region-wide over the
weekend. While most locations will exceed 25 mph gusts on
Saturday, winds will peak on Sunday. Most valleys should expect
30-35 mph gusts, and higher elevations (particularly over the
San Juans) are on tap for 40-50 mph gusts. With relative
humidity in the single digits for much of the CWA, Sunday is on
track to be a potentially critical fire weather day as well.

As the trough axis pushes into eastern Utah overnight Sunday
into Monday morning alongside the passage of a cold front,
temperatures cool off and a mild surge of moisture brings us
relief from fire concerns. High temperatures should drop 5 to 10
degrees below normal on Monday before steadily rising
throughout the mid-week amidst deformation in the flow aloft.
While the uptick in moisture will be moderate at best, this
upper-level support and lift from the accompanying cold front is
expected to bring a bout of precipitation primarily across the
northern CWA. During the cooler Monday conditions, snow is
likely at high elevations with valley rain. However, as things
warm up into Tuesday and Wednesday, precipitation will be
predominantly rain. Wherever snow does present itself, snow-
liquid ratios will likely be very low and accompanied by rain.
Winds shouldn`t be as impactful during this mid-week period, but
some 20+ mph gusts may continue to be seen during afternoons
throughout the week. Models diverge significantly after this, so
it is difficult to say if this active pattern will persist
later into the week or not.

&&

.AVIATION /06Z TAFS THROUGH 06Z SATURDAY/...
Issued at 1119 PM MDT Thu Apr 24 2025

High clouds will continue to stream over the area tonight
through tomorrow. The big concern will be gusty winds for all
TAF sites in the afternoon with gusts of 25 to 40 mph expected.
VFR conditions will continue.

&&

.FIRE WEATHER...
Issued at 333 PM MDT Thu Apr 24 2025

Critical fire weather conditions are expected Friday afternoon
and evening, and potentially, through the weekend. Wind gusts
on Friday are expected to range from 25 to 35 mph and possibly
a bit higher at times for some locales. Meanwhile, humidity
drops to the single digits/low teens for much of the region.
Since green up has yet to occur for Colorado Fire Weather Zones
207, 292 and 203 and 205 below 7000 feet, fuels have been
deemed critical in those areas. Therefore, a Red Flag Warning
remains in effect on Friday from noon through 8PM for the
previously listed zones. Similar conditions are expected on
Saturday so a Fire Weather Watch remains in effect for the same
zones and times. Since there`s a very good chance that critical
fire weather conditions will redevelop on Sunday with winds
strengthening ahead of an approaching cold front, a Fire
Weather Watch for Sunday afternoon/evening has been added to the
existing highlights.

&&

.GJT WATCHES/WARNINGS/ADVISORIES...

CO...Red Flag Warning from noon to 8 PM MDT Friday for COZ203-205-
     207-292.
     Fire Weather Watch from Saturday afternoon through Saturday
     evening for COZ203-205-207-292.
     Fire Weather Watch from Sunday afternoon through Sunday
     evening for COZ203-205-207-292.
UT...None.

&&

$$

SHORT TERM...NL
LONG TERM...BW
AVIATION...TGJT
FIRE WEATHER...TGJT