Area Forecast Discussion
Issued by NWS Grand Junction, CO

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FXUS65 KGJT 281015

Area Forecast Discussion
National Weather Service Grand Junction CO
415 AM MDT Fri Oct 28 2016

.SHORT TERM...(Today through Saturday)
Issued at 414 AM MDT Fri Oct 28 2016

After several days of warm and dry weather across the forecast
area, the pattern is finally shifting and becoming a bit more
active as Pacific energy rolls into the Great Basin. Fairly
vigorous upper level low remains just off the West Coast early
this morning with healthy band of showers pushing across central
California per west coast radars and satellite. Out ahead of this
activity, moisture profiles have been slowly improving with fairly
widespread mid and high level cloud decks in place. Story for
today will be how fast can we drive the deeper moisture into our
area and just how warm will we get today before the showers

High resolution models in good agreement with holding off
precipitation until very late this afternoon or more likely after
sunset. This will keep the forecast area dry today and with
increasing southwest flow, we should mix out a little better. This
will add a couple degrees to the max temps experienced yesterday,
but still under record values even with breaks in the cloud
cover. So have trimmed pops back today and nudged temps up
slightly from yesterday. Also ticked the winds up slightly for
this afternoon as any developing virga/showers will drive down a
few stronger gusts.

After sunset, the Pacific system will be ejecting northeast across
the Great Basin and filling as it arrives. This will result in an
increasing threat for showers overnight with a few rumbles of
thunder not out of the question. Precipitable water values climb
to 200 percent of normal or around three quarters of an inch
tonight. So even with the wave losing power as it arrives, have
increased pops a bit and we may still be a little low. After all,
the system is coming in at night, which fits the profile for
precipitation occurrence across our forecast area based on
numerous local studies.

By Saturday morning, this system will be exiting to the northeast
with showers ending as shortwave ridge slides overhead. Cooling
will be modest at best with this wave with max temps Saturday
afternoon still running a good 5 degrees above seasonal normals.

.LONG TERM...(Saturday night through Thursday)
Issued at 414 AM MDT Fri Oct 28 2016

The next system is moving onto the West Coast early Sunday and
quickly moves over the northern Rockies by early Monday morning.
Best chances for preciptation will be over the north Sunday
afternoon through early Monday. Again the higher elevations are
favored although this system brings in a colder air mass and
would expect snow levels to be lower, especially across the north.

Clearing after Monday with only a few lingering showers over the
higher elevations Monday afternoon. The next system slides down
the California coast Tuesday. This system is taking a more
southern track although the timing is very uncertain as models
very greatly. Temperatures will be backing down to more seasonal
values for much of the week.


.AVIATION...(For the 12Z TAFS through 12Z Saturday morning)
Issued at 414 AM MDT Fri Oct 28 2016

Moisture will continue to spread eastward over the next 24 hours
as a Pacific storm moves across the southwest U.S. Expect a few
showers to develop over the higher terrain after 18z with activity
increasing and spreading into the valleys after 00z this evening.
The showers will help to drive down stronger winds with gusts up
to 40 mph possible this afternoon and evening. As the showers
develop and increase in coverage, expect CIGS to drop with local
ILS conds expected, especially at higher terminal sites such as
KTEX and KASE. The showers will linger through the overnight




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