194
FXUS65 KVEF 041038
AFDVEF

Area Forecast Discussion
National Weather Service Las Vegas NV
338 AM PDT Mon Aug 4 2025

.KEY MESSAGES...

* Above-normal temperatures, afternoon southwesterly breezes, and
  dry conditions continue through the forecast period.

* Extreme Heat Watch in effect for southern zones Wednesday and
  Thursday.

&&


.DISCUSSION...Today through Monday.

Dry southwesterly flow will persist over our forecast area through
the week into next weekend. This is the result of persistent
troughing over the Pacific Northwest and ridging over the Four
Corners region. Over the next couple of days, the Pacific Northwest
trough will push inland across the Intermountain West, which will
work to deamplify the Four Corners ridge somewhat. Heights will
decrease slightly across the region, which will maintain afternoon
high temperatures 1 to 3 degrees above seasonal normals. Formerly,
we expected the Intermountain West trough to push the Four Corners
high eastward enough to allow monsoonal moisture to surge up the
Colorado River Valley. While PWATs will increase to 50-75% of normal
along the CRV, it will not be enough to translate to mentionable
PoPs in our forecast area. Expect sunny skies and breezy south-
southwesterly winds each afternoon. These southwesterly winds will
result in hazy-to-smoky conditions across portions of southeastern
California and southern Nevada over the next few days from the
Gifford Fire, which is around 65,000 acres and is situated north of
Santa Barbara.

Through the week, the Four Corners ridge of high pressure will
continue to build over the Desert Southwest. There is some
uncertainty regarding how westward this ridge will retrograde mid-to-
late week, resulting in some MaxT model spread. Regardless, expect
widespread Moderate (Level 2 of 4) HeatRisk Wednesday and Thursday,
with Major (Level 3 of 4) HeatRisk spread across southern Mohave,
southern San Bernardino County, and the Colorado River Valley. As a
result, there remains an Extreme Heat Watch for these areas on
Wednesday and Thursday.
&&


.AVIATION...For Harry Reid...For the 12Z Forecast Package...South-
southeasterly gusts will continue at least intermittently through
the remainder of the overnight period, with gust speeds 10-15 kts.
Late-morning into early-afternoon, southwesterly gusts will pick up
to 20-25 kts, with gusts decreasing in speed and frequency after
sunset. South-southwesterly winds will remain elevated overnight.
Slantwise visibility restrictions expected in the Daggett corridor
from smoke from the Gifford Fire in southeastern California.
Greatest instance of smoke/haze will be between 15 and 19Z today,
with possible surface visibility restrictions. Temperatures will
increase above 100 degrees between 19 and 03Z.

For the rest of southern Nevada, northwestern Arizona and
southeastern California...For the 12Z Forecast Package...Late-
morning into early-afternoon, southwesterly gusts pick up in Las
Vegas Valley and Colorado River Valley TAF sites around 25 kts. KDAG
will gust from the west with speeds 25-30 kts. KBIH will experience
isolated gusts from the south-southeast before shifting from the
northwest. Gusts decrease in speed and frequency after sunset.
Slantwise visibility restrictions expected in the Daggett corridor
from smoke from the Gifford Fire in southeastern California.
Greatest instance of smoke/haze will be between 15 and 19Z today,
with possible surface visibility restrictions at all TAF sites
except KBIH.
&&


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

&&

$$

DISCUSSION...Soulat
AVIATION...Soulat

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