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Area forecast discussion 
National Weather Service Grand Junction Colorado
315 am MDT Thursday Aug 25 2016

Short term...(today through friday)
issued at 315 am MDT Thu Aug 25 2016

While moisture remains about average for this time of year, an
upper level trough will continue to slowly move over the area.
This trough will bring some cooling aloft which will cause some
destabilization this afternoon and evening so expect another day
of scattered showers and thunderstorms. Convection will begin
around noon, if not a bit before, and will increase in coverage as
the day progresses. Vorticity fields also show several maximas
moving over the area from 3pm onwards with no one area really
favored. Heavy rain can be expected under the stronger cells while
forecast skew- ts also indicating dry mid-levels which is
favorable for hail formation so some small hail can't be ruled
out either. Plenty of mid to high level clouds will also be around
which will keep temperatures relatively cool for this time of
year. Some showers and a few rumbles of thunder will carry into
the overnight hours but coverage will be much less than seen
today.

The trough doesn't move much and will remain the focus of our
weather into Friday with more of the same expected. Steering level
winds do look to be a little stronger so storms that form won't be
as stationary as they have been. Temperatures will remain on the
cool side.

Long term...(saturday through wednesday)
issued at 330 PM MDT Wed Aug 24 2016

The weakened Great Basin trough lifts out and shifts east
beginning Friday night and into Sunday. This will eventually
result in a gradual drying trend which will become noticeable on
Sunday. Until then, however, the chance of showers and
thunderstorms will persist into Saturday, mainly during the late
day periods. The southern portion of the County Warning Area will be favored but
activity will be possible over all areas.

On Sunday, drier conditions begin to take hold as high pressure
begins to build over the region and the subtropical moisture
plume will lean over into the central Continental U.S.. models indicate that
this drier and warmer pattern will then persist through the end of
the long term period. Temperatures will climb to a little above
normal for the first half of the new work week.

&&

Aviation...(for the 12z tafs through 12z Friday morning)
issued at 315 am MDT Thu Aug 25 2016

Fairly widespread convection will start firing between 16z to 18z
and become widespread from 21z onwards. Some of the showers and
thunderstorms that form will bring heavy rain, some small hail,
and gusty outflow winds. Mid level ceilings will be the rule today
but under the stronger convection, brief MVFR conditions are
possible. Tafs will indicate thunderstorms in the vicinity for airports though no tempo
groups yet. Between 03z and 06z convection will drop markedly
though some showers and a few storms may persist overnight. Expect
a repeat performance on Friday.

&&

Gjt watches/warnings/advisories...
Colorado...none.
Utah...none.
&&

$$

Short term...tgr
long term...eh
aviation...tgr

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