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Area forecast discussion
National Weather Service Grand Junction Colorado
537 PM MDT Fri Aug 23 2019

Short term...(tonight through Saturday night)
issued at 305 PM MDT Fri Aug 23 2019

After any shower or thunderstorm dissipates this evening an
extended dry period enters the picture under a persistent
northwest flow pattern. Still hoping red flag conditions become a
bit more widespread this afternoon...but the same showers we were
hoping to help push up the wind are also pushing up the relative humidity. Clear
conditions will be setting up this evening which should lead to a
decent cool down and hedged the lows down just a tad toward or
below the cooler guidance numbers. A larger scale trough will be
digging across the west.Canadian provinces on Saturday which will
push a bit of high level moisture into the region. This is bumping
up the precipitable water just a bit in the form of some passing high
cloudiness. Temperatures under this regime will stay well above
normal.

Long term...(sunday through friday)
issued at 305 PM MDT Fri Aug 23 2019

Strong negative height anomalies Will Park over c.Noam into early
next week with the expected positive anomalies hanging out along
the Pacific coastline. The main concern for our area will be gusty
afternoon winds as mixing will be deep and tapping into the
stronger thermal winds aloft. So hot and dry conditions with
breezy afternoons can only main one thing...fire weather concerns.
This first concern for widespread critical fire weather
conditions come on Sunday afternoon across northern portions of
the region and watches are now in effect. Each afternoon through
the middle of next week could be of concern as we remain on the
edge or under the jet. The pattern begins a shift toward the
latter half of the week pushing the subtrop high back toward the 4
corners region. This will slowly draw moisture back northward but
there is not a real strong signal for widespread precipitation
until Friday and beyond.

&&

Aviation...(for the 00z tafs through 00z Saturday evening)
issued at 537 PM MDT Fri Aug 23 2019

Shower and thunderstorm remnants will die out early this evening,
and this activity is not expected to impact taf sites. Thereafter,
expect decreasing clouds and light terrain driven winds after
dark. Dry weather expected on Saturday with winds becoming a bit
breezy during the afternoon. VFR conditions will persist through
the next 24 hours with no chance for ceilings below ils breakpoints.

&&

Fire weather...
issued at 305 PM MDT Fri Aug 23 2019

Gusty southwest winds associated with a trough over southern
Wyoming are occurring in localized areas over portions of
northwest Colorado this afternoon. On Sunday, northwest winds
aloft are expected to mix down leading to strong winds at the
ground over a more widespread area of northeast Utah and northwest
Colorado. These winds will combine with the continually dry
conditions to again meet or exceed critical conditions.

&&

Gjt watches/warnings/advisories...

Colorado...Fire Weather Watch from Sunday afternoon through Sunday evening
for coz200-202.

Red flag warning until 8 PM MDT this evening for coz200-202.

Utah...Fire Weather Watch from Sunday afternoon through Sunday evening
for utz486-487.

&&

$$

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