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739
FXUS65 KGJT 250421
AFDGJT

Area Forecast Discussion
National Weather Service Grand Junction CO
1021 PM MDT SAT SEP 24 2016

.UPDATE...
Issued at 841 PM MDT Sat Sep 24 2016

Precipitation across northwest Colorado into the I-70 corridor has
been a little slower than expected in winding down. IR satellite
images still show moisture upstream across southern WY. Therefore
have upped pops/clouds somewhat for the next few hours. Do not
expect much in the way of additional snow accumulations along the
Park, Elkhead and Flat Tops mountains as snow seems to be on the
light side based on the few observations and web camera shots
available. Conditions are still expected to improve by late
tonight with precipitation ending before dawn. Otherwise no other
changes to the grids.

&&

.SHORT TERM...(Tonight through Monday)
Issued at 252 PM MDT Sat Sep 24 2016

A few rain and snow showers hanging on late this afternoon in
wrap-around flow as the main upper low continues to lift northeast
into the North Dakota. HRRR and RAP keep the light showers rolling
through late this evening, before shutting things down as mid
level flow becoming more north to northeasterly introducing more
of a downsloping component for much of our forecast area. Cloud
cover will be the big factor with potential freezing temperatures
overnight with our higher valleys the biggest concern. Steamboat,
Craig and Gunnison have all had hard freezes earlier this month
and other guidance in remaining high valleys holds temps up a bit
with clouds and higher surface moisture in place. Will hold off
on an highlights for freezing temps at this time with expectation
that any run to or slightly below freezing will be very late and
short-lived. Secondary concern will be areas of fog in the
valleys late tonight and have this covered in the latest forecast
package.

Sunday and Monday will be dry with high pressure building
overhead. This will result in light winds, seasonal daytime highs
and cool overnight lows.

.LONG TERM...(Monday night through Saturday)
Issued at 252 PM MDT Sat Sep 24 2016

Upper level ridging will be migrating east Monday night and
Tuesday with southwest flow returning by midweek. Pattern looks to
remain dry through Tuesday before moisture starts lifting back
north into the southern zones on Wednesday as the remnants of
another tropical system get caught up in the flow. ECMWF and GFS
in decent agreement with kicking a wave out across the forecast
area Thursday with additional energy to follow through the
weekend. So after a slow start to this extended period, things
will become more interesting as we close out the week with rain
and mountain snow returning to the forecast.

&&

.AVIATION...(For the 06Z TAFS through 06Z Sunday night)
Issued at 1021 PM MDT Sat Sep 24 2016

Clouds with some showers will continue to stream into the area
from the north late this evening and into the late night hours.
However moisture will diminish with a general clearing trend
becoming more apparent by around 08z. The cloud deck is mostly
mid level, but north of and along the Colorado Tavaputs Plateau
and the Flat Tops clouds will be lower until around 09z with MVFR
or even IFR conditions possible. Mountain obscurations in fog, low
clouds or snow will be likely along the Divide from the central
Colorado mountains northward becoming more spotty towards dawn. In
addition, a few valley areas may see fog develop late tonight and
then persist until the daylight hours. Airfields most likely to be
affected will be KCAG, KHDN, KSBS and TAF site KASE. Otherwise VFR
conditions are expected and will spread area wide by mid morning.
Mostly clear skies will then dominate through Sunday evening.

&&

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

$$

UPDATE...EH
SHORT TERM...JDC
LONG TERM...JDC
AVIATION...EH