Area Forecast Discussion
Issued by NWS Grand Junction, CO

Home | 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 37 38 39 40 41 42 43 44 45 46 47 48 49 50

000
FXUS65 KGJT 261702
AFDGJT

Area Forecast Discussion
National Weather Service Grand Junction CO
1102 AM MDT FRI AUG 26 2016

.SHORT TERM...(Today through Saturday)
Issued at 242 AM MDT Fri Aug 26 2016

A few showers continue at this hour but these are very few and far
between. Plenty of convection continues, however, over Arizona and
New Mexico due, in large part, to a weak jet streak moving over
their area. We remain under the right entrance region of the jet
stream so increasing showers and storms are not out of the
question this morning. Pops reflect this possibility.

An upper level trough remains situated over the northern Rockies
down to the Great Basin and today models depict another short wave
moving through this trough. Lapse rates and cold air advection
are not `too` impressive so forcing from the shortwave and
orographics will be the kickers to this afternoon`s convection. A
rather sloppy V-profile shows up in forecast Skew-Ts so some gusty
outflow winds are possible again with some heavy rainers mixed in
as well. The San Juans look favored at this time though areas from
the Roan/Tavaputs southward will likely see some convection this
afternoon and evening.

As has been the case over the last few nights, a few stray showers
and storms will persist overnight but with the loss of daytime
heating, not much to be concerned about.

The main trough that has remained to our west will finally move
over the area Saturday on its way to the Plains. Both the NAM and
GFS are highlighting a closed low forming over southern NV, CA,
and western AZ with convection again for our CWA favoring the same
areas as today. So, expect another variably cloudy day with
cooler than normal temperatures and some showers and storms across
the region.

Interesting to note that some snow has fallen at the highest
elevations (mostly a dusting) of the San Juans over the last few
days and expect this trend to continue today and possibly
Saturday.  Quite early for the `S` word!

.LONG TERM...(Saturday night through Thursday)
Issued at 157 PM MDT Thu Aug 25 2016

The longwave pattern changes little over the weekend with a large
area of low pressure over the western and central states and high
pressure over the SE U.S. and the Gulf of Mexico. This will allow
a small monsoon feed from west of the Big Bend area through New
Mexico and into southern CO. The northern half of the forecast
area will remain drier and under the col between the westerly flow
over the northern tier states and the trough over the Great Basin
and the southwest. Monday through Thursday should be drier as the
weak monsoonal feed collapses to the south and east and no systems
move in from the west.

&&

.AVIATION...(For the 18Z TAFS through 18Z Saturday afternoon)
Issued at 1102 AM MDT Fri Aug 26 2016

A quieter morning is on tap behind a departing system which
brought snow to much of the timberline region overnight. Isolated
to scattered storms will again develop as the afternoon progresses
but confidence not quite as high as days past on location and
timing. Hi-res models suggest kvel/kcny may have the best
probability in the first six hours as storms move off the wasatch.
Storms and showers look likely to continue into the early morning
hours. Gusty winds and lightning will remain threats with many
storms today with small hail also possible with the stronger
storms in the valleys and many areas of the high country.

&&

.GJT Watches/Warnings/Advisories...
CO...None.
UT...None.
&&

$$

SHORT TERM...TGR
LONG TERM...CC
AVIATION...TGJT


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