Area Forecast Discussion
Issued by NWS Las Vegas, NV

Home |  Current Version |  Previous Version |  Text Only |  Print | Product List |  Glossary Off
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42
029
FXUS65 KVEF 030515
AFDVEF

Area Forecast Discussion
National Weather Service Las Vegas NV
1014 PM PDT Wed Jul 2 2025

.KEY MESSAGES...

* Widespread showers and thunderstorms are will continue through the
  evening as a low pressure system moves through. Sudden strong wind
  gusts will again be a concern.

* Drier conditions resume by Friday with a warming trend heading
  into next week.

* Breezy conditions and low humidity will lead to elevated fire
  danger for the 4th of July.

&&

.DISCUSSION...Today through the Middle of Next Week.

Scattered showers and thunderstorms will continue to develop across
the region and stream north through the day. The forecast for day
remains on track from previous thinking with no significant chances
in the expected impacts and thunderstorm areas. Instability
increases this afternoon with CAPE over 500-1000 J/Kg developing
across southern Nevada and western Arizona. This combined with upper
level forcing with an incoming upper level low will result in more
widespread and organized thunderstorms versus yesterday. PWATs have
increased in the past 24 hours, which inherently would decrease the
wind threat compared to yesterday. However, yesterday`s set up
lacked instability and organized thunderstorm structure, so even
though low levels have moistened per the 12Z Las Vegas sounding,
there is still an inverted-V signature on the sounding and added
instability means there is still a threat for sudden gusty downburst
winds today. HREF has a high chance (70%) for wind gusts over 40 MPH
with areawide thunderstorms, and a low chance for wind gusts up to
60 MPH centered over southern Nevada. In addition today, with
increased moisture and training thunderstorms, heavy rain and
isolated flash flooding is possible. The highest risk for heavy
rain should be in northern Mohave County where better moisture and
instability overlap as well as far southern Clark County where HRRR
model radar output suggests training storms. As instability wanes
after sunset, precipitation will also diminish. The latest HRRR runs
does hang on to precipitation through much of the night in Mohave
County which is the outlier compared to other hi-res model runs.
However, the HRRR solution does have some meteorological support as
the upper level low will be moving into Nevada and increased forcing
could allow for additional overnight develop. Later shifts will need
to monitor trends as a solution like the HRRR would result in
continued heavy rain and isolated lash flood threat overnight.

As the low moves eastward and weakens Thursday, drier air will
gradually work east. This will result in some lingering activity
Thursday afternoon across Mohave County and perhaps Lincoln and
Clark Counties. Thunderstorms on Thursday could produce sudden gusty
winds but the threat would be lower and more isolated than today.
Drier air will sweep through area wide by Friday with temperatures
hovering near to slightly below normal over the weekend before a
warming trend begins next week.

Thunderstorm activity will trend wetter today which should limit the
coverage of Dry lightning, though western areas of the Great Basin
and parts of the Mojave Desert may still see relatively little
rainfall with the storms. Nonetheless, surface dewpoints will keep
minimum RH values elevated and help to improve the fire danger
somewhat. However, breezy southwesterly winds on Friday will return
with much drier air pushing in, and will result in elevated fire
danger Friday, just in time for the 4th of July.

&&

.AVIATION...For Harry Reid...For the 06Z Forecast Package...A few
lingering thundershowers will continue through midnight, mainly near
and west of the Spring Mountains.  Another area of convection over
northwest Arizona will impact the Peach Springs corridor for a few
more hours before also decreasing. Winds will turn westerly around
midnight, and then become light and variable before sunrise.  East
to southeast winds are expected by late morning, and a few gusts to
20 knots will be possible after 19Z.  After a dry morning,
additional showers and thunderstorms are expected to develop in the
afternoon across southern Nevada and northwestern Arizona.
Thunderstorms should be more isolated than today, but could still
produce lightning, gusty outflow winds, brief heavy rain, and CIGs
below 10kft

For the rest of southern Nevada, northwest Arizona and southeast
California...For the 06Z Forecast Package...Conditions at the Las
Vegas area TAF sites will be similar to those described above for
Harry Reid.  Elsewhere, scattered convection is expected on Thursday
afternoon, with additional thunderstorm impacts possible across
southern Nevada and northwestern Arizona. However, these impacts are
expected to be more isolated than those seen today.  Convection is
expected to end across southern Nevada by early evening and across
northwest Arizona by late evening tomorrow.  Winds will generally
follow typical diurnal patterns in the Owens Valley and western
Mojave Desert. In the Colorado River valley, southerly winds are
expected, although they will be more subject to convective
influences during the afternoon and evening.


&&

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

&&

$$

DISCUSSION...Nickerson
AVIATION...Planz


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