169
FXUS65 KVEF 012300
AFDVEF

Area Forecast Discussion
National Weather Service Las Vegas NV
400 PM PDT Mon Sep 1 2025

* Monsoonal moisture returns tomorrow with scattered thunderstorms
  possible across western and southern portions of the CWA.

* Thunderstorm chances linger into the second half of the week as
  increased moisture levels remain in place over the eastern third
  of the CWA.


.DISCUSSION...This afternoon through Sunday.

A ridge of high pressure building eastward across the area will
maintain above normal temperatures and widespread "Moderate" Heat
Risk levels, with pockets of "High" Heat Risk in the lower desert
valleys, including Death Valley, Pahrump Valley, the southern
portions of the Las Vegas Valley, and the Colorado River Valley. The
one exception to this will be in the higher elevations of Mohave
County, where isolated thunderstorms capable of producing gusty
winds are possible into this evening.  As the ridge shifts further
east into the more traditional Four Corners location tomorrow, an
increase in a southerly moisture influx is expected.  At the same
time, a shortwave will push into the California Coast.  The forcing
from the shortwave, along with PWATs increasing to over 1.00" across
the southern two-thirds of the CWA, will increase storm chances and
coverage tomorrow and Wednesday, with moderate-to-heavy rainfall,
isolated flash flooding, and frequent lightning being the primary
hazards.

By the second half of the week, the ridge will weaken and shift to
the east, scouring the moisture out in a northwest-to-southeast
direction.  Precipitation will generally be confined to our eastern
zones by Friday, but may linger in these areas through the weekend.
Temperatures will also fall to below normal levels by mid-week and
remain cooler than normal into the weekend.

&&

.AVIATION...For Harry Reid...For the 00Z Forecast Package...Quiet
conditions continue into tonight as winds largely remain below 10
knots and follow typical patterns. Early Tuesday morning, some
showers/virga may be in the vicinity as moisture surges in. The
extent of morning cloud cover and precipitation will influence the
chances of additional convection Tuesday afternoon and evening,
which will pose a threat of gusty outflow winds should it develop.
Increasing clouds tonight and tomorrow, with scattered to broken
conditions expected between 10-12kft. Temperatures fall below 100F
by 04z tonight, potentially exceeding this threshold once again
tomorrow between 22z and 02z.

For the rest of southern Nevada, northwest Arizona and southeast
California...For the 00Z Forecast Package...Mostly clear skies
across the region with just some isolated convection in eastern
Mohave County this evening. Any elevated breezes today will wane
after sunset. Overnight, moisture will surge in from the southeast,
bringing increased cloud cover and scattered showers/virga with it.
The extent of this activity will influence the odds of additional
convection Tuesday afternoon and evening. Best chances for afternoon
showers/storms seem to be across the Mojave Desert and along the
Sierra. Gusty outflow winds are likely with any storms that develop.
Lowest cloud bases generally 10-12kft.

&&


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

&&

$$

DISCUSSION...Planz
AVIATION...Woods

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