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fxus65 kvef 192130 
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Area forecast discussion
National Weather Service Las Vegas Nevada
230 PM PDT Sat Oct 19 2019

Synopsis...dry and seasonable weather is expected through the
week. Periodic northerly breezes are likely, especially down the
Colorado River valley, Sunday and Thursday.

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Discussion...through next Saturday.

A shortwave trough is moving into the central Idaho mountains this
afternoon. Surface observations and radar continue to detect light
rain showers along the I-80 corridor from Salt Lake City west to
Winnemucca Nevada. The precipitation is forecast to sag as far south as
Highway 50 and the central Utah mountains this evening and
overnight. Likely see some lower ceiling below 10 kft in the
Panhandle of Lincoln County tonight. Otherwise, ceilings expected to
stay above 12 kft across the rest of southern Nevada and the Mojave
Desert tonight.

Surface high pressure building in behind the exiting shortwave
trough across northeast Nevada/northern Utah will shift winds out of
the north later tonight and Sunday. Those winds will be strongest
within the Lake Mead National Recreation Area and lower Colorado
River valley. Won't be the best day to venture onto Lake Mohave but
no wind products will be issued as forecast speeds/gusts look to
stay just shy of thresholds.

Near normal temperatures today will fall some 4-6 degrees below
normal Sunday.

Area will lie under a dry northwest flow aloft during the first half
of the week with a strong ridge of high pressure situated over the
eastern Pacific. Temperatures will warm back to normal while the
northerly winds within the lower Colorado River gradually relax.

During the second half of the week, we see the longwave pattern
undergo amplification. As ridge builds northward, models in good
agreement showing downstream shortwave trough diving south through
the Rocky Mountain states Wednesday/Thursday. This will send another
dry cold front our way leading to a resurgence of north wind and
cooler temperatures Thursday. Ensemble and deterministic solutions
showing support for a deeper/colder trough developing in the
intermountain west downstream of the strong Pacific Ridge early in
the week of October 27.

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Fire weather...westerly breezes and low relative humidity will make for elevated
fire danger into this evening across the southern Great Basin,
however winds look below red flag criteria. Those elevated fire
conditions shift into the lower Colorado River valley Sunday due to
gusty northerly winds and low relative humidity values. A resurgent period of north
winds is expected Thursday following the passage of another dry cold
front.

&&

Aviation...for McCarran...light and variable winds are expected
to continue through the afternoon, favoring an easterly direction.
Some breezy west to southwest winds may develop later this evening
but confidence is low that these winds will make it to klas. More
likely, winds will follow typical drainage southwest winds through
the evening. By 09-11z tonight, winds will shift to a northerly
direction as a cold front moves through the region, but winds will
generally remain below 10 knots. By 16-17z tomorrow morning,
occasionally breezy northeast winds will move through the valley,
with some gusts to 20 knots. Scattered to bkn aoa 25 kft expected through
tomorrow.

For the rest of southern Nevada, northwest Arizona and southeast
California...light and variable winds are expected across much of
the region this afternoon. Though, some breezy to gusty west to
northwest winds will develop across central Nevada and southeast California
later this afternoon and early this evening, mainly impacting kbih
and kdag with gusts to 20-25 knots. Through Sunday, occasionally
breezy northerly winds will move through the region before funneling
down the Colorado River valley. This will impact kifp and keed where
gusts to 30 knots are possible tomorrow afternoon. No operationally
significant clouds expected through tomorrow.

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Spotter information statement...spotters are encouraged to report
any significant weather or impacts according to Standard operating
procedures.
&&

$$

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