Area Forecast Discussion
Issued by NWS Grand Junction, CO

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FXUS65 KGJT 142052
AFDGJT

Area Forecast Discussion
National Weather Service Grand Junction CO
152 PM MST Sat Jan 14 2017

.UPDATE...
Issued at 151 PM MST Sat Jan 14 2017

Dense fog has persisted in Hayden early this afternoon. Dense Fog
Advisory has been extended for this zone until 5pm. ALl other
zones previously in the Dense Fog Advisory have been allowed to
expire.

&&

.SHORT TERM...(Today through Sunday)
Issued at 333 AM MST Sat Jan 14 2017

The closed low responsible for the clouds and precipitation over
the last few days has managed to reach the west coast of the Baja
Peninsula at this hour and will continue to drift to the southeast
over the next few days. Ample moisture remains across our area as
PWATs and specific humidities remain elevated. Like yesterday, not
much advection taking place aloft or at the surface and with
clouds still in the picture, temps will remain very similar to
yesterday. Before getting into the precip forecast, important to
mention the moisture is also causing plenty of fog, some dense,
across eastern Utah and western Colorado. Many sites are reporting
fog with visibilities varying from 5 miles to 1/4 mile. No brainer
to keep the dense fog advisories going through the mid-morning
hours.

As far as precipitation is concerned, models continue to
highlight widespread precipitation for the CWA for the overnight
becoming focused over the San Juans from about noon time onwards.
Local observations and webcams do show rain and snow for many
areas this morning but generally light. Short range models are
also in agreement with this widespread precip ending, or becoming
much lighter, shortly after daybreak and then the San Juans get
the next shot. The winter highlights look to be in good shape so
will leave as is for this mornings package. So, a few showers
possible outside of the San Juans with clouds continuing for most
of the forecast area.

By this evening and into Sunday, the low pressure will have moved
to just south of New Mexico and will start moving towards the
northeast. The location of the low and easterly flow will start
favoring the Colorado Plains and southern portions of the Front
Range as our precipitation finally starts winding down. The
mountains along the Continental Divide will see some snowshowers
continuing but the heavier precipitation will be just about done.
Would like to say the sun returns but that doesn`t look to happen
until Monday so one more day of some grey skies though the sun
will peek through from time to time. Also, temperatures will drop
a few degrees, 3 to 5, Sunday afternoon and into Monday as winds
become northerly allowing some cooler air to move in.

.LONG TERM...(Monday through Friday)
Issued at 315 PM MST Fri Jan 13 2017

The models are in good agreement that we will finally see a break
from this steady stream of moisture and active weather beginning
Monday afternoon and lasting through Wednesday night as high
pressure moves in over the Great Basin and lays over the region,
with a much drier airmass in place. As this occurs though, another
low pressure system will be moving into the Pacific Northwest with
moisture increasing across eastern Utah and western Colorado by
Thursday morning. So, after our brief dry spell Monday through
Wednesday, the weather will become more active again Thursday
through at least the weekend as Pacific storms barrel across the
region bringing more Pacific moisture which in turn means more
snow for the mountains, with a mix in the valleys.

&&

.AVIATION...(For the 18Z TAFS through 18Z Sunday afternoon)
Issued at 1100 AM MST Sat Jan 14 2017

A Pacific storm passing to the south will continue to generate
precipitation south of the I-70 corridor through the next 24
hours. This will result in prolonged periods where CIGS are below
ILS breakpoints at KTEX due to snow, possibly mixed with rain
later this afternoon. In addition, IFR/LIFR VSBY and CIGS will
exist through the early part of the afternoon. In contrast, KDRO
will experience VFR conditions behind the band of showers which
moved through this morning. This will change later tonight as the
next wave of moisture arrives driving CIGS into the MVFR range and
below ILS breakpoints. Warmer temperatures at KMTJ has resulted in
rain and CIGS below ILS breakpoints which will persist through the
early part of the afternoon. It`s likely that vsby will not be
degraded below VFR, however.

Lingering moisture should result in CIGS below ILS breakpoints at
KEGE and KASE. KASE may also see brief snow showers during the
afternoon. Meanwhile, KGJT, KMTJ, and KRIL face little chance for
precipitation through the next 24 hours with VFR conditions
likely, though there will be fog in the vicinity late tonight
through midmorning Sunday.

Finally, moisture trapped beneath a weak 7H level inversion over
the eastern Uinta Basin will keep low stratus in the picture over
KVEL through the next 24 hours.


&&

.GJT WATCHES/WARNINGS/ADVISORIES...
CO...Winter Weather Advisory until 5 PM MST this afternoon for COZ009-
     012-017-018.

     Winter Storm Warning until 5 PM MST this afternoon for COZ019.

     Dense Fog Advisory until 5 PM MST this afternoon for COZ002.

UT...Winter Storm Warning until 5 PM MST this afternoon for UTZ028.

&&

$$

UPDATE...MAC
SHORT TERM...TGR
LONG TERM...MDA
AVIATION...NL



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