Area Forecast Discussion
Issued by NWS Grand Junction, CO

Current Version | Previous Version | Text Only | Print | Product List | Glossary Off
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

FXUS65 KGJT 261102

Area Forecast Discussion
National Weather Service Grand Junction CO
502 AM MDT Sat May 26 2018

.SHORT TERM...(Today through Sunday)
Issued at 122 AM MDT Sat May 26 2018

Everything is still supporting the critical fire weather
conditions later this morning into this evening, as increasing
southerly winds aloft mix down to the surface in a very dry
airmass. H7 temperatures today expected to be about the same as
yesterday. However, usually the stronger the surface winds the
more likely there will be a slight damper on surface temperatures
being as warm as yesterday at most locations. Nonetheless, will be
expecting max temperatures today to be close to record highs in a
few places.

Surface winds should begin to decouple from the winds aloft around
sunset this evening, and with the very dry air and few clouds
would expect good radiational cooling overnight. Therefore, min
temperatures tonight are likely to be slightly below normal at
most locations.

The main upper level low will be slowly pushing eastward across
northern Utah on Sunday. Still seeing very dry conditions ahead
of the trough up across our CWA on Sunday. Locally breezy
conditions will continue with little change in temps south of a
line from Blanding northeast to Gunnison. Noticeable cooling
anticipated sunday due H7 temperatures expected to drop 4-6C
lower than today, along with a little increase of mainly high
clouds. Max surface temperatures on Sunday should be 6 to 10
degrees F lower than today across our CWA.

.LONG TERM...(Sunday Night through Friday)
Issued at 325 PM MDT Fri May 25 2018

Gradients continue to weaken Sunday night into Monday with
moisture profile slowly improving from northwest to southeast.
This will result in isolated convection on Monday with activity
increasing Monday night and Tuesday as we see a cold front and
upper level trough swing through from the northwest. Moisture
lingers on the backside of this exiting system to keep low pops in
the forecast through Wednesday. Then we take another turn back
towards the hot, dry and windy weather to close out the week as
another low pushes into the intermountain west.

Temperatures will be running 5 to 10 degrees above normal Sunday
with readings dropping back early in the week, only to return to
the much above normal readings by the end of the week.


.AVIATION...(For the 12Z TAFS through 12Z Sunday morning)
Issued at 448 AM MDT Sat May 26 2018

A southerly flow aloft and dry air will result in VFR conditions
across the area through at least the next 24 hours. Southerly
surface winds will increase by late this morning or early
afternoon at all TAF sites, with gusts of 25-30 knots or greater
after 18z. Surface winds will be decreasing around sunset this
evening and drop to less than 10 knots at most airports by 04Z.


Issued at 122 AM MDT Sat May 26 2018

Still expecting widespread critical fire weather conditions across
western CO and SE/E-Central UT later this morning and into this
evening, with strong winds aloft mixing down to the surface under
a 60-70 knot upper level jet, low relative humidities, near record
high temperatures, and dry vegetation.

As mentioned above, surface winds should begin to decouple from
the winds aloft around sunset this evening and significantly
decrease by late evening. Then on Sunday expect surface winds much
less than today as surface pressure gradient should be weaker and
winds aloft should have about 50 percent lower velocities.
Although low RH values are expected to persist across the area on
Sunday, weaker surface winds will not support critical fire weather

It`s looking like a return to critical fire weather conditions
by Thursday of next week and perhaps continuing into Friday as
another Pacific low is expected to approach our area from the


CO...Red Flag Warning from 10 AM this morning to 10 PM MDT this
     evening for COZ200-202-203-205-207-290>295.

UT...Red Flag Warning from 10 AM this morning to 10 PM MDT this
     evening for UTZ490-491.



FIRE WEATHER...JRP is the U.S. government's official web portal to all federal, state and local government web resources and services.