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Area forecast discussion 
National Weather Service Las Vegas Nevada
910 PM PDT Wednesday Jul 9 2014

Synopsis...any storms the rest of tonight should be confined to
northwest Arizona. Gradual drying will take place from west to east
by Friday with thunderstorm chances limited to Mohave County by
Friday through Sunday. Monsoon moisture returns next week.

Update...much quieter this evening as thunderstorms over the desert
of San Bernardino County and Mohave County for the most part have
dissipated. Radar detecting light showers over east central Mohave
County along I-40 and northeast of Peach Springs. 00z GFS shows the
potential for a slight chance of a shower or thunderstorm mainly
east of line from Caliente-Mesquite-Peach Springs the rest of
tonight. West of that line skies will be partly to mostly cloudy.
Updated package out.

Aviation...for McCarran...south-southwest wind around 10 kts will
develop at the terminal shortly and persist through the rest of the
night. Winds will go light and variable Thursday morning before
transitioning more southwesterly during the afternoon. The exception
on Thursday will be the potential for gusty and erratic winds due to
thunderstorms and outflow. Broken ceilings above 10 kft tonight with a
chance of ceilings scattering out Thursday morning. Thunderstorms
mostly likely to affect Mormon Mesa and Peach Springs corridors

For the rest of southern Nevada...northwest Arizona...and southeast
California...slight chance of showers or thunderstorms mainly east
of a line from Caliente-Mesquite-Peach Springs tonight. Same GOES
for Thursday with greatest thunderstorm coverage over southeast
Nevada and northwest Arizona. Storms will lead to gusty and erratic
winds, while away from storms wind speed generally between 5 and 15

Discussion...some lingering light showers stretched from roughly
Las Vegas southward toward Essex...but are dissipating. This and
associated cloud cover have limited temperatures and will also limit
convection a bit this afternoon for the central portion of the
forecast area. However...thunderstorms have developed across the
higher terrain from Inyo eastward to northern Mohave. These areas
are the likely suspects this afternoon and there is
some interaction between the upper level high and a weak shortwave
trough to our northwest. Slow moving storms producing heavy rain can
be expected. Outflow from these storms may work to lower elevations
and force new convection later this evening. Another area to watch
will be southern Mohave and eastern San Bernardino counties...where
a remnant mesoscale convective vortex from convection last night is noticeable spinning on
satellite imagery. This has the potential for increased forcing
across that area where dewpoints and precipitable waters are elevated...but so far
things are fairly quiet down there.

Relatively dry and stable air to our southwest is projected to
gradually push east and north Thursday and Friday. The GFS seems to
be a little too eager to push the moisture out...but eventually the
vast majority of the forecast area will become dry. The only probability of precipitation we
have going Friday are mainly across Mohave County. Have continued to
back down the probability of precipitation across that area as some models that originally
lingered the moisture are now coming in dry with the southwest flow.
So Friday may be dry across the entire area.

The dry southwest flow will continue through the weekend...with just
that isolated chance across Mohave County as the upper level high
shifts east. This high pressure will begin to drift back toward the
area by Sunday. By Sunday night monsoon moisture will filter back
into the forecast area. Guidance is in fairly good agreement
bringing a better push of moisture in here Monday through
Tuesday...then decreasing a bit Wednesday. As with the previous
forecast...have increased probability of precipitation across the entire County Warning Area for Monday and
Tuesday then backed down a little for Wednesday. Still left the
western deserts dry Monday and Tuesday...but that may very well
change in coming forecasts.

As for temperatures...a warming trend is expected through the
weekend as dry air works across the region. Temperatures should push
107-110 in the Las Vegas area and along the Colorado River
Sunday...while lower 120s in Death Valley will be common. As
moisture increases late Sunday and into the new work week...temperatures
will trend cooler. Temperatures next week should be similar to what
we have experienced the last few days.

Spotter information statement... spotter activation is not expected
at this time. However...spotters are encouraged to report any
significant weather conditions according to Standard operating


discussion/aviation: paddock

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