Scientific Forecaster Discussion
fxus65 kvef 210912
Area forecast discussion
National Weather Service Las Vegas Nevada
212 am PDT Wed Aug 21 2019
Synopsis...sunny and dry conditions continue as we hit midweek and
will continue into the weekend. Temperatures expected to Max out
today, though temperatures between 5 and 8 degrees above seasonal
averages are expected to persist through the forecast period. No
clear sign of a monsoonal moisture return at this time, though
modest moisture is expected to creep back into the area next week.
Discussion...today through Wednesday.
As mentioned in previous discussions, we are sitting under a pretty
expansive ridge whose center slowly drifts west from New Mexico.
Through the remainder of the work week, this ridge is expected to
push further westward, resulting in a continuation of above-average
temperatures. Afternoon highs are expected to Max out today with a
high temperature at McCarran International Airport forecast at 109f;
the average this time of year is 101f.
Thursday Onward, temperatures are expected to dip slightly, though
will remain 5-8 degrees above average for the remainder of the
forecast period. No changes have been made to the excessive heat
warning issued for much of the area that extends through Thursday
evening. Though temperatures have trended slightly downward and look
to be about borderline-warning-criteria for Thursday, high
temperatures will still classify as "extreme" and precautions and
preventative heat-impact measures should still be taken.
The most "heat relief" through the weekend will take place in
eastern San Bernardino County and southern Mohave County where a
modest moisture flux will help bring high temperatures below the
century mark - albeit, briefly.
Temperatures next week are expected to approach extreme values once
again, particularly along the Colorado River valley and lower
elevations of Inyo County Tuesday. Will continue to monitor and
issue heat-related headlines as we get closer and confidence
Concurrently, dry conditions area-wide expected for the start of the
work week, though some models are hinting at an increase in moisture
up the Colorado River valley by mid-week. Will this moisture be
enough to revamp monsoon season 2019? It's still too far out too
know for certain, but will be interesting to see how models resolve
this reserved increase in moisture moving forward.
Fire weather...dry conditions with above-average temperatures will
continue through the week and into the weekend. Minimum humidities
expected to remain in the single-digits with poor overnight
recoveries. The exception will be southern Mohave County and eastern
San Bernardino County this weekend which will see minimum relative humidity values
in the teens thanks to a modest moisture flux with area-wide
overnight recoveries between 30 and 40%.
Aviation...for McCarran...very little change in the weather pattern
will provide hot and dry weather. A light easterly wind will develop
late this morning. Brief period for southeast winds possible
between 22-23z as winds shift more southerly in the late
For the rest of southern Nevada, northwest Arizona and southeast
California...very little change in the weather pattern will provide
hot and dry weather. Typical daily wind cycles with sustained speeds
generally less than 15 knots at all taf sites. The exception would
be around kdag where wind gusts may gust up to 25 kts this
Spotter information statement...spotters are encouraged to report
any significant weather or impacts according to Standard operating