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000
FXUS65 KGJT 172256
AFDGJT

Area Forecast Discussion
National Weather Service Grand Junction CO
456 PM MDT Sun Jun 17 2018

.SHORT TERM...(Tonight through Monday night)
Issued at 238 PM MDT Sun Jun 17 2018

Drier air will move across our area this evening as the closed-low
continues to spin over northern Nevada. Short-range models show
activity moving east and out of the forecast area overnight with
the best focus this evening over the northern and central
mountains of western Colorado. Drying continues on Monday as the
closed-low moves slightly north into southern Idaho. Models
continue to advertise a slight tightening of the pressure gradient
gradient late tonight and early Monday. However, as the system
moves north during the day, models show a slight decrease in
gradient by the afternoon hours. As mentioned in the previous
discussion, conditions may approach critical fire weather
conditions across some areas but still looks marginal, so have
held off on any fire weather highlights at this time. See Fire
Weather section below for further details.

.LONG TERM...(Tuesday through Sunday)
Issued at 238 PM MDT Sun Jun 17 2018

The closed-low will move north to southern Montana and remain
nearly stationary and slowly weaken on Tuesday as the southwest
gradient relaxes over the forecast area. High pressure will build
over the western US as the closed-low slowly reflects east over
the northern Great Plains by later Wednesday. Expect slightly
cooler temperatures on Wednesday with isolated/chance showers and
thunderstorms across the north later Tuesday into Wednesday as
this system moves east. Mainly dry and warmer conditions are
expected for the remainder of the work week with some isolated
late-day showers and thunderstorms across the northern and central
mountains. Another trough is forecasted to drop across the
northern Great Basin region by late Friday and move east across
Wyoming by the weekend. The biggest impact from this system will
be wind at the onset, with a slight chance of showers and
thunderstorms across the northern half of the forecast area by the
latter half of the weekend.

&&

.AVIATION...(For the 00Z TAFS through 00Z Monday evening)
Issued at 453 PM MDT Sun Jun 17 2018

Drier air will continue clearing showers and thunderstorms out of
the area from SW to NE this evening. Storm will still occasionally
affect KRIL, KEGE, KASE, KTEX and KHDN until about 04z. These
airports can expect gusts to 30 kts when storms are close. After
04z VFR conditions will prevail through Monday.

&&

.FIRE WEATHER...
Issued at 238 PM MDT Sun Jun 17 2018

A disturbance over northern Nevada will shift slightly north to
southern Idaho by Monday. This system will bring breezy southwest
winds and drier conditions over the area by Monday afternoon.
Current forecasts are showing winds and relative humidity
approaching critical fire weather conditions over Utah zones
487...490 and 491 and Colorado zones 202...203...and 290. At this
time confidence is marginal for widespread critical fire weather
conditions for these areas, but stay tuned to latest forecast
overnight for any changes.

&&

.GJT WATCHES/WARNINGS/ADVISORIES...
CO...None.
UT...None.
&&

$$

SHORT TERM...MPM
LONG TERM...MPM
AVIATION...CC
FIRE WEATHER...MPM