558
FXUS65 KVEF 160716
AFDVEF

Area Forecast Discussion
National Weather Service Las Vegas NV
1216 AM PDT Wed Sep 16 2026

.KEY MESSAGES...

* Isolated-to-scattered showers and thunderstorms expected today
  and Thursday across our eastern zones.

* Elsewhere, expect breezy south-southwesterly wind gusts through
  the week with dry conditions and near-normal temperatures.

&&

.DISCUSSION...Today through Tuesday.

Expecting isolated-to-scattered showers and thunderstorms this
afternoon across Lincoln and Mohave counties, with chances
spreading into Thursday morning. While the southern Great Basin
remains situated under a dry southwesterly flow aloft, the
southern Mojave Desert will experience a south-southeasterly flow,
which will usher in 1.25 to 1.75 inches of PWAT into the region -
specifically southeastern Nevada and northwestern Arizona. In
addition to the moisture, there is a disturbance riding up the
Baja California that is currently highlighted by the NHC as having
a 10 percent chance of tropical storm formation in the next 48
hours. While this disturbance is unlikely to become a cyclone, as
it pushes northward, the vorticity maxima associated with it will
lead the development of showers and thunderstorms across southern
Mohave County / the lower Colorado River Valley this afternoon.
Additionally, energy riding along the upper-level trough across
the western CONUS has closed off over northern California this
morning and will begin its meander eastward across Nevada this
afternoon. The enhanced jet associated with this closed low will
combine with daytime heating to facilitate convection across
eastern Lincoln, eastern Clark, and Mohave counties, which is in-
line with the latest CAM guidance. That said, there is a noticable
PWAT gradient across the center of our forecast area, which could
act as a dryline, resulting in convection developing a bit
further west than guidance currently suggests. Will continue to
keep an eye on locations along and west of Interstate 15 as the
day progresses. As a result of ample instability and moisture,
thunderstorms that form are expected to be efficient rain- makers
with frequent lightning, which will elevate the risk of flash
flooding, particularly across Mohave County and underneath
training storms. Forecast HRRR soundings in south-central Mohave
County show over 1750 J/kg of SBCAPE, 750-1000 J/kg of DCAPE, 1.50
inches of PWAT, and 500 mb cooling (LIs around -4 degrees C), so
severe thunderstorms are likely as well.

The trough axis associated with the aforementioned closed low will
push through the forecast area today and Thursday, resulting in
elevated south-southwesterly winds with gust speeds generally
between 25 and 35 mph. Cannot rule out occasional gusts to 40 mph
in the higher terrain. Otherwise, persistent troughing over the
western CONUS will result in afternoon high temperatures near-
normal for mid-September. Cloud cover heading into overnight
periods may result in elevated morning lows, however.

&&

.AVIATION...For Harry Reid...For the 06Z Forecast Package...Light
southerly winds tonight give way to another round of gusty south-
southeast breezes Wednesday morning, gradually turning to a true
south direction in the afternoon. On average, wind direction during
from 16z-22z will be ~160, but brief periods as far east as 120 are
possible. Gusts of 20-30 knots are likely (70%) from 17z - 04z.
Winds weaken after sunset. Few to scattered clouds around 10kft with
temperatures remaining below 100F.

For the rest of southern Nevada, northwest Arizona and southeast
California...For the 06Z Forecast Package...Light winds tonight with
another round of gusty south-southeast breezes on Wednesday in most
locations. Gusts generally 20-30 knots, but would not be surprised
to see a few ~35 knot readings in the Owens Valley and lower
Colorado River Valley. The latter will likely be induced by outflow
from thunderstorms expected in western AZ. Best storm chances (40-
60%) are in far southern and northern Mohave County Wednesday
afternoon and evening. The more robust convection will be capable of
producing strong outflow winds, hail, and heavy rain. Few to
scattered clouds around 10kft, with greater coverage in locations
with the best storm chances.

&&

.SPOTTER INFORMATION STATEMENT...Spotters are encouraged to report
any significant weather or impacts according to standard operating
procedures.

&&

$$

DISCUSSION...Soulat
AVIATION...Woods

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