Scientific Forecaster Discussion

Return to Local Conditions & Forecast

Without Abbreviations
With Abbreviations

fxus65 kgjt 291750 
afdgjt

Area forecast discussion
National Weather Service Grand Junction Colorado
1150 am MDT Wed Mar 29 2017

Short term...(today through thursday)
issued at 415 am MDT Wed Mar 29 2017

Skies are clearing across the County Warning Area this morning as yesterday's
storm system continues to slide east into the Great Plains. The
0600z nam12 and gfs20 have initialized well with the synoptic
scale weather pattern and indicate that a ridge of high pressure
will reside over the intermountain west today and tomorrow morning
maintaining dry weather through at least tomorrow afternoon.

A short term weather concern is present along Highway 550 through
the San Juan Mountains where gusty northerly winds are occurring.
Winds have been gusting to 35 mph all night with a few higher
gusts to 65 mph observed over higher terrain. These wind gust
values are below our thresholds for wind advisories but can make
travel difficult, especially for high profile vehicles. High
resolution forecast models indicate that these conditions will
continue through approximately 1000 am MDT to 1200 PM MDT.

Warm southerly winds are anticipated for Thursday ahead of an
approaching storm system. These warm southerly winds will aid
afternoon temperatures increasing 5 to 10 degrees over those
observed today. This additional warming will result in a pleasant
day, however the warming may also help to destabilize the
atmosphere supporting showers and afternoon thunderstorms on
Thursday.

Long term...(thursday night through tuesday)
issued at 415 am MDT Wed Mar 29 2017

The satellite water vapor image is showing a developing storm
system approaching the coast of British Columbia. The 0600z gfs20
and 0000z European model (ecmwf) have initialized well with this synoptic scale
weather feature and move it into the Pacific northwest later
today. This cold weather system will begin to impact eastern Utah
and the western slope Thursday afternoon, bringing rain to the
valleys and mountain snows to the area.

Snow levels are anticipated to drop to 5,000 to 6,000 feet Friday
morning with the mountains expecting to see 5 to 10 inches of snow
with locally higher amounts possible. Lapse rates are anticipated
to increase as cold air moves in aloft resulting in a possibility
of afternoon thunderstorms Friday afternoon. Moderate to heavy
snow fall rates will be possible with these thunderstorms. At this
point in time we have issued a Special Weather Statement as a
heads up for this storm system. Please keep an eye out for
forecast updates including the possibility of winter weather
advisories and maybe even winter storm warnings.

The previously mentioned storm system will slowly exit the area
Saturday night/Sunday morning. A brief period of dry weather is
anticipated on Sunday before the next next storm system moves in
on Monday.

&&

Aviation...(for the 18z tafs through 18z Thursday afternoon)
issued at 1150 am MDT Wed Mar 29 2017

VFR conditions are expected to prevail over the next 24 hours as
drier air moves in from the north behind the departing storm
system. Some low and mid level clouds will still linger over the
higher terrain along the western Colorado Divide through mid
afternoon, affecting taf sites like kase, kege and ktex. However,
overall sky conditions will be partly to mostly sunny across the
region. Some breezy conditions will occur this afternoon at
times, but this should lessen this evening with typical diurnal
terrain-driven winds taking hold. High clouds will increase
Thursday morning ahead of the next storm system.

&&

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

National Weather Service Glossary of Abbreviations