Area Forecast Discussion
Issued by NWS Grand Junction, CO

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FXUS65 KGJT 221658

Area Forecast Discussion
National Weather Service Grand Junction CO
1058 AM MDT Mon Jul 22 2019

.SHORT TERM...(Today through Tuesday)
Issued at 401 AM MDT Mon Jul 22 2019

Possibly aided by the cold pool from the robust early morning lee
side convection...low level moisture is making a push back north
into our southern CWA. This will help fuel thunderstorms later
today across our southern mountains which will be drifting
southward through the evening thanks to the upper high building
into Redrock Country. Would expect at least isolated activity over
most mountain ranges today as we bring in more moisture aloft as
well. However there is this subsidence ridge aloft so confidence
not strong at all. Fully expect convection to settle down by
midnight but that may depend on outflow boundary interaction.
Surface high pressure to our East and deepening low pressure to
our Northwest leads to another surge of moisture from the south
per ~315K theta surface. PWATs again jump on Tuesday and models
are painting the best coverage of storms over the southern and
eastern hills. Temperatures remain above normal to hot the next
few afternoons with lows staying mild to warm overnight.

.LONG TERM...(Tuesday night through Sunday)
Issued at 401 AM MDT Mon Jul 22 2019

Models continue to spike PWAT over our CWA during the mid week
period as the northern amplification of the ridge is squashed and
the moisture plume to our West is carried our way by increasing
westerlies. This will lead to better storm coverage...more
cloudiness and hence cooler temperatures. Still expect a trend
downward to or below normal Wednesday and Thursday but blended
models are not quite biting on this yet. Deep warm and moist
profiles suggest very efficient warm rain processes going into
this period which brings a heavy rain rate threat into the
picture. The jet stream is dipping farther into the mid latitudes
by the weekend which pushes the subtrop high and moisture to our
south drying things back out. Expect temperatures to push back
upward as a result. Luckily swamp coolers should be working a bit
better by then as dewpoints decrease.


.AVIATION...(For the 18Z TAFS through 18Z Tuesday afternoon)
Issued at 1058 AM MDT Mon Jul 22 2019

Isolated to scattered showers and thunderstorms will develop along
the Continental Divide and across the Eastern Uinta Mountains
between 18Z and 20Z. Convection will persist this evening before
ending by 06Z tonight. KTEX, KDRO and KGUC are most likely to see
storms at/in the vicinity with KASE and KMTJ having the potential
as well. In storms, expect brief MVFR CIGS/VIS and gusty outflow
winds. Widespread VFR conditions are expected from 06Z tonight
through at least 15Z Tuesday.




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