Area Forecast Discussion
Issued by NWS Grand Junction, CO

Home |  Current Version |  Previous Version |  Text Only |  Print | Product List |  Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46
410
FXUS65 KGJT 172002
AFDGJT

Area Forecast Discussion
National Weather Service Grand Junction CO
202 PM MDT Tue Jun 17 2025

.KEY MESSAGES...

- Red Flag Warnings remain in effect for southwest Colorado
  through 8 PM this evening.

- After a seasonable day tomorrow, more hot, dry, and windy
  conditions return Thursday and persist into the weekend
  bringing widespread critical fire weather conditions.

- Triple digit highs will spread across a majority of the desert
  valleys Thursday into Friday.

&&

.SHORT TERM /THROUGH WEDNESDAY/...
Issued at 158 PM MDT Tue Jun 17 2025

Satellite imagery early this afternoon shows that the axis of
an upper-level shortwave trough has pushed east onto the Front
Range leaving behind a more stable environment in its wake.
Isolated storms remain possible (15-30% chance) over the high
terrain north of I-70 this afternoon with gusty outflow winds
and lightning being the main threats. Red Flag Warnings also
remain in effect for portions of southwest Colorado this
afternoon and evening. Please see the Fire Weather section below
for more details.

A quiet day is on tap tomorrow with seasonal temperatures and
lighter winds as an upper-level ridge begins to build in across
the Intermountain West.

&&

.LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
Issued at 158 PM MDT Tue Jun 17 2025

The main story for late this week into the coming weekend is a
return to hot, dry and windy conditions after a brief "cooldown"
following today`s shortwave trough passage with potential for
widespread critical fire weather conditions and stronger winds.

The ridge of high pressure will slide eastward Thursday as a
low pressure trough deepens over the Pacific Northwest and edges
southward into the Great Basin this weekend. This pattern
appears to remain stagnant potentially through early next week
as some sort of blocking regime sets up. The western slope will
draw more of the dry southwest flow from the Desert Southwest
with a peak in winds Friday and Saturday. Winds will pick up
across northeast Utah and northwest Colorado Thursday and become
more widespread across the entire CWA by Friday and Saturday as
a robust jet streak parks itself for a few days across western
Utah. Most model guidance is indicating southwest winds to gust
upwards of 35 to 45 mph, perhaps a bit higher where a discussion
on Wind Highlights might be necessary in addition to critical
Fire Weather concerns. Relative humidities look to be in the
single digits for a good portion of the CWA through the long
term period. There is some potential that a bit of moisture is
drawn northward early next week across the Divide and Front
Range, but low confidence in this scenario, although it could
raise relative humidity enough to move a few areas outside of
critical fire weather thresholds.

Bottom line: Thursday and beyond look to be hot, dry and
windy...especially Friday and Saturday with potential gusts to
45 mph or higher and widespread critical fire weather
conditions. Temperatures will average about 10 degrees above
normal with triple digit heat being felt once again across the
lower desert valleys of west-central Colorado and eastern Utah
Thursday through at least Friday and potentially into Saturday
given deeper mixing.

&&

.AVIATION /18Z TAFS THROUGH 18Z WEDNESDAY/...
Issued at 1147 AM MDT Tue Jun 17 2025

FEW to SCT cloud cover will be passing through the region this
afternoon and some isolated to scattered storms and BKN cloud
cover mainly across northwest Colorado and the northern
mountains. KHDN and KEGE stand the best chance to see impacts
mainly in terms of gusty winds to 40 mph and lightning, so
included VCTS through early afternoon (about 21Z). Breezy
afternoon winds will be seen otherwise at most sites with gusts
20 to 30 mph at times. Skies clear behind this system by late
afternoon/early evening and overnight. VFR conditions will
prevail despite any storm activity.

&&

.FIRE WEATHER...
Issued at 158 PM MDT Tue Jun 17 2025

Surface observations show that low RH values 5-10% and gusty
winds up to 40 mph have taken hold in parts of SW CO this
afternoon. As such, the Red Flag Warning remains in effect
through 8 PM this evening. Localized critical fire weather are
also likely north of I- 70, especially in UT Fire Zone 487 and
CO Fire Zone 200.

After a brief lull in critical fire weather conditions on
Wednesday, hotter and windier conditions return to end out the
week. Several days of critical fire weather is expected which is
likely to stress fuels across the area. The hot dry and windy
index is forecast to exceed the 90th percentile in many areas
during this time.

&&

.GJT WATCHES/WARNINGS/ADVISORIES...

CO...Red Flag Warning until 8 PM MDT this evening for COZ290>295.
UT...None.

&&

$$

SHORT TERM...KAA
LONG TERM...MDA
AVIATION...TGJT
FIRE WEATHER...TGJT