320
FXUS65 KVEF 142329
AFDVEF

Area Forecast Discussion
National Weather Service Las Vegas NV
429 PM PDT Sun Sep 14 2025

.KEY MESSAGES...

* High pressure building across the Southwest will keep conditions
  warm and dry through midweek.

* Increasing shower and thunderstorm activity is anticipated
  Thursday through the weekend, though details such as coverage
  and rainfall amounts remains uncertain.

&&

.DISCUSSION...through this weekend.

High pressure ridge will continue to build across the region
through Wednesday, with dry conditions continuing as well as a
warming trend over the next few days. The average last 100 degree
day of the year in Las Vegas is around September 18th, and by
Wednesday NBM probabilities climb to 10% for reaching 100. As
moisture and cloud cover increases on Thursday, temperatures will
begin to trend downward through the weekend. While temps will be
above normal, heat risk remains pretty firmly in the minor
territory outside of the lower reaches of Death Valley and the
Colorado River Valley.

Meanwhile, Tropical Storm Mario has regenerated this morning in
the Eastern Pacific and will gradually trek northwest over the
next couple days before eventually dissipating. As its remnants
drift northward they will become entrained in the flow thanks to a
weak low lurking off the SoCal Coast, and eventually spread north
into the Mojave Desert and southern Great Basin by late week.
Overall, forecast guidance remains in pretty agreement on this
general concept of moisture advancement into the region. What`s
less certain is if there will be favorable forcing features (jet
streak, shortwaves, boundaries, etc) present to act on this
moisture. This makes details like precipitation coverage and
amounts less certain, but for now the fairly widespread 20-50
percent PoPs late in the week and into the weekend look pretty
good and are in agreement with our general messaging. Stay tuned
over the coming days as we better hone in on the potential for
heavier rainfall and areas of more concentrated activity.

&&

.AVIATION...For Harry Reid...For the 00Z Forecast Package...This
afternoon through early evening, prevailing winds are expected to
be southeasterly with sustained speeds under 10KT. However, some
variability and intermittent thermally-induced gusts to around
10-15KT can be expected until sunset. Thereafter, winds become
light with speeds under 8KT, following typical diurnal directional
patterns. VFR conditions prevail, with temperatures under 100
degrees.


For the rest of southern Nevada, northwest Arizona and southeast
California...For the 00Z Forecast Package...Across the region,
winds will generally follow typical diurnal directional patterns
the next 24 hours. Intermittent gusts to around 10-20KT are
possible through sunset today, with sustained speeds dropping to
around 10KT or less after sunset areawide. Winds Monday are
expected to be lighter than today, though gusty up-valley winds to
around 20KT are expected through portions of the Owens Valley
Monday afternoon, including at KBIH. VFR conditions prevail.

&&

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

&&

$$

DISCUSSION...Outler
AVIATION...Phillipson

For more forecast information...see us on our webpage:
https://weather.gov/lasvegas or follow us on Facebook and Twitter