Scientific Forecaster Discussion
fxus65 kvef 252154
Area forecast discussion
National Weather Service Las Vegas Nevada
254 PM PDT Mon Sep 25 2017
Synopsis...decreasing northerly breezes with gradually increasing
temperatures into mid-week for the region. Expect dry weather for
most with any shower and storm chances limited to northwest
Arizona on Wednesday.
Not much if any changes in ongoing forecast.
The focus for the next few days will be low closing off over the
lower Colorado River valley. The pressure gradient (and associated
winds) along the River Valley is expected to maintain or weaken
through tomorrow. Given the borderline nature of the winds today,
opted to leave the Current Lake Wind Advisory as-is, expiring this
evening. For Wednesday, as the low lingers in the lower Colorado
River valley, moisture is wrapped around, bringing shower and
thunderstorm chances to northern Mohave County before the low
begins to lift out of the region on Thursday.
As heights rebound, temperatures should as well through the end
the of the week. The only item of note that could force some
changes to the extended was disagreement between operational and
ensemble runs regarding how warm temperatures get at the end of
the week. Quite a few gefs members are trending cooler and both
the operational runs of the GFS and European model (ecmwf) actually lie on outside
their respective ensembles on the hot side.
Fire weather...expect decreasing northerly winds and gradually
increasing temperatures over the next several days. Afternoon
humidities will fall near 5-15 percent for the deserts, 20-30
percent for the mountains; and recover to 25-30 percent for the
deserts and 50-60 percent for the mountains. No critical fire
weather is expected through the period.
Aviation...for McCarran...north to northeast winds are expected to
gradually decrease through the afternoon/early evening hours, then
transition to a northwest direction overnight. Occasional gusts 15-
20 kts possible. There is a chance that if speeds diminish enough
tonight they could take on a southwest direction. Very similar
conditions are expected Tuesday and Wednesday.
For the rest of southern Nevada, northwest Arizona and southeast
California...north winds of 5-12 kts continue to dominate across the
region today, with isolated areas along the Colorado River valley
seeing gusts of 20-30 kts. Winds will taper off somewhat during the
overnight hours. Similar conditions are expected Tuesday and
Spotter information statement...decreasing northerly breezes and
a warming trend are expected through the week. Spotter activation
will not be needed through the end of the week.