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FXUS65 KVEF 260520

Area Forecast Discussion
National Weather Service Las Vegas NV
1020 PM PDT Sun Aug 25 2019

.SYNOPSIS...Extreme heat is likely through at least midweek under
a strong ridge of high pressure. There are signs of moisture 
moving into the area by midweek, which may limit heat impacts. Dry
conditions are expected to persist through the week along with 
another potential period of hot temperatures next weekend.


.UPDATE...Another quiet evening is in store to round out the 
weekend. Gusts have ceased with a few spots still seeing sustained 
winds of 10 to 15 mph this evening. High clouds will continue to 
stream northward across the area tonight through much of the day 
tomorrow with temperatures reaching several degrees above normal. 
Dew points in the mid 50 to even low 60s remain in the Colorado 
River Valley and adjacent areas, but with little upper level 
support, should continue to have little noticable effect during the 
day other than folks feeling more of the humidity in the air. 

Previous Discussion 233 PM PDT Sun Aug 25 2019

.DISCUSSION...Heat will be the main concern through midweek. Under 
the influence of high pressure temperatures will to near record 
temperatures Monday through Wednesday. Lower valleys across southern 
Nevada (i.e. Pahrump valley, Las Vegas valley) will see highs 
between 106-110 on Tuesday and Wednesday; the Colorado River is 
expected to see highs between 110-115 over the same period. Moisture 
could be the limiting factor. That is, if enough moisture funnels 
in, temperatures would be moderated and are unlikely to reach full 
heating potential. All that said, heat risk and impacts will elevate 
this week, so an Excessive Heat Watch has been issued for the 
aforementioned areas covering Tuesday and Wednesday. 

Other than heat impacts, there will be a slight chance for isolated 
thunderstorms across the southern Sierra Tuesday afternoon/evening 
as remnants energy from Ivo ejects into northern California. 
Elsewhere, chances for showers/storms is very low. The best chances 
for southern Nevada will be Tuesday/Wednesday over the higher 
terrain, though this will depend on the depth of moisture spread 
into our area and the degree of warmth aloft. Most areas will likely 
see only increased cumulus due to the increased moisture and 
continued capping.

The ridge dominating the southwest will begin to shift westward 
later in the week, centering the dome of high pressure over SoCal. 
This pattern would favor hot and dry conditions as dry west to 
southwest flow is aimed across the Mojave Desert and southern Great 
Basin. This may end up as one of the hottest August on record.&&

.FIRE WEATHER...Continued hot temperatures and lighter winds 
expected through the week under high pressure influence. 
Exceptionally dry conditions will continue across the southern Great 
Basin, while moisture funneled into the Mojave Desert will keep 
humidities slightly above critical. Uncertainty exists in deeper 
moisture surges and thunderstorm potential for much of the upcoming 

.AVIATION...For McCarran...Light and variable winds will return in 
the morning, eventually becoming easterly in the afternoon hours. 
Due to the light nature of the winds in the afternoon, a high amount 
of variability is expected, likely between 020-160 degrees but 
generally below 8 kts. Skies should remain mostly clear with minimal 
impacts expected. 

For the rest of southern Nevada, northwest Arizona and southeast 
California...Minimal impacts expected again for the 06Z TAF period. 
Some initial wind gustiness tonight at KDAG will gradually diminish 
by the morning hours becoming light through much of the day 
tomorrow. Otherwise, no significant aviation concerns expected. 


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



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