Area Forecast Discussion
Issued by NWS Grand Junction, CO

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FXUS65 KGJT 260903
AFDGJT

Area Forecast Discussion
National Weather Service Grand Junction CO
303 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 12Z TAFS through 12Z Saturday morning)
Issued at 242 AM MDT Fri Aug 26 2016

Another active day in store as a trough and shortwave move over
the area. Currently, mountain obs show IFR conditions with low
ceilings while TAF sites remain VFR though some mid level clouds
are getting close to MVFR for TEX. Once the sun rises, expect VFR
for all sites though this will be short-lived as convection fires
again increasing chances for stronger showers and thunderstorms.
VCTS looks a safe bet for all TAF sites from about noon through
the evening hours. Gusty outflow winds and heavy rain will be the
biggest concerns.

&&

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

$$

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


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