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Area forecast discussion
National Weather Service Grand Junction Colorado
354 PM MDT Wed Oct 16 2019

Short term...(tonight through friday)
issued at 354 PM MDT Wed Oct 16 2019

Critical fire weather then a cooler pattern is shaping up for
Thursday into the late week period. The upper ridge over The Spine
of The Rockies this afternoon will be shifting eastward and
replaced by the upstream trough currently bringing rain/snow to
the pacnw. We can expect some precipitation to occur over our County Warning Area
but not before we get another breezy and warm afternoon on
Thursday. High cloudiness could hamper temperatures a bit but good
mixing ahead of an approaching cold front should push
temperatures up some 5 to 8 degrees above normal in most areas.
Moisture transport into this extremely dry airmass is subtle
early on Thursday with isentropic surfaces showing an initial feed
from the south. Moisture will then increase later in the day as
the better Pacific feed moves in with the jet ejecting from the
upstream trough. There could be some elevated convection forming
ahead of the cold frontal passage late tomorrow afternoon but see
very little chance of any precipitation to the ground. The
stronger forcing remains north of our County Warning Area but ascent from the cold
front and instability aloft will bring somewhat widespread
precipitation to all but the southeast County Warning Area. Rainfall will be the
main ptype below all but the highest elevations through late
evening. Colder air filtering in will drop snow levels down to as
low as 7000 ft Friday where it will stall through the daylight
hours. A fairly good punch of snow could be occurring over the
higher peaks down to 9000 feet over the northern and central
Colorado mountains Friday morning...maybe Red Mountain also. The
passes may be a bit sketchy early but sun angle and temperatures
should limit impacts by early afternoon. Overall expecting 2 to 3
inches from the west elks up to the park with isolated 4 to 6
inch measurements possible. Temperatures will drop back below
normal on Friday.

Long term...(friday through wednesday)
issued at 354 PM MDT Wed Oct 16 2019

Temperatures will rebound back toward normal on Saturday ahead a
much colder system diving into The Rockies Saturday night. Again
the strongest ascent is trending north of of our County Warning Area and moisture
at the moment is not quite as robust. However colder temperatures
and strong cold air advection could bring conditions more favorable for the
champagne snow we expect in this area. Will leave the finer
details for a later discussion but this could be a decent storm
from the northern San Juans up through the northern Colorado
Mountain ranges through Monday afternoon. A stronger cool down
will occur behind this second system before a gradual warmup
begins through midweek.


Aviation...(for the 18z tafs through 18z Thursday afternoon)
issued at 1118 am MDT Wed Oct 16 2019

Minimal concerns for aviation over the next 24 hours as skies
remain mostly clear with just passing high cloudiness. Winds will
be increasing late Thursday morning with gusts over 25 mph likely
at many taf sites after this 18z forecast.


Fire weather...
issued at 354 PM MDT Wed Oct 16 2019

Widespread critical fire weather conditions are expected Thursday
afternoon across much of northwest Colorado and east-central
Utah...with localized areas possible elsewhere. The upper ridge
will be breaking down as an upstream system approaches
Thursday...a known pattern for creating windy and dry conditions
as temperatures remain well above normal. Much cooler conditions
follows the passage of the cold front which should decrease fire
weather concerns. Most of the precipitation will be in the
Colorado central and northern mountains with only small chances of
wetting precipitation elsewhere.


Gjt watches/warnings/advisories... flag warning from noon to 7 PM MDT Thursday for coz200>203-
205-290-292. flag warning from noon to 7 PM MDT Thursday for utz487-490.



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