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673
FXUS65 KVEF 231706
AFDVEF

Area Forecast Discussion
National Weather Service Las Vegas NV
1006 AM PDT Sun Jun 23 2024

.SYNOPSIS...Very hot conditions will remain in place through the
middle of next week with temperatures running 5 to 8 degrees
above normal each day. Entrenched moisture over central and
southern Mohave County will spread into San Bernardino and Clark
Counties today. Shower and thunderstorm coverage will increase
this afternoon for areas generally south and east of the I-15
corridor. Indications are that moisture remains anomalously high
through midweek but will show a declining trend beginning Monday.
Shower and storm activity after Sunday will be mostly confined to
Mohave County.

&&

.UPDATE...
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Moisture has arrived in Las Vegas with 0.97" inches of
precipitable water (PW) on this morning`s sounding. That`s a 0.57"
increase from yesterday`s 12Z sounding and 0.50" above average for
this time of year. Despite the anomalous PW on this morning`s
sounding the lower levels of the atmosphere remain dry as indicated
by the inverted V-shape in the lower levels of the sounding. This
inverted V-shape in the lower levels of the sounding combined with
1,900+ J/kg of DCAPE point towards an increased risk of strong
outflow winds from any storms that develop this afternoon. Speaking
of afternoon storms, the latest HiRes guidance has convection
beginning to fire in Mohave County around 18-19Z (11 am-12 pm PDT)
with southern Clark County, eastern Lincoln County, and portions of
San Bernardino County joining the party a few hours later. As was
previously mentioned, winds will be one of the primary threats with
today`s storms along with periods of moderate to heavy rain and
lightning.
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&&

.SHORT TERM...Through Monday.

Moisture will continue to increase today with better shower and
thunderstorm coverage this afternoon, primarily along and
southeast of Interstate 15, but we could possibly see a few cells
form in eastern Lincoln County as well. The primary concerns for
cells today will be gusty outflow winds and dangerous lightning.
An isolated flash flood threat cannot be ruled if cells train
over the same area. Today marks the first day of Lightning
Awareness Week so look for posts related to various lightning
topics on our social media pages later this morning. Yesterday,
temperature were very hot across the region with Las Vegas
reaching 110 degrees. In addition, it may have felt a little
muggier in parts of the area today with surface dewpoint
temperatures about 10-15 degrees higher then Friday.

There is some decrease in precipitable water overall on Monday
when compared to Sunday but still, anomalous moisture remains
entrenched with PWATs 200-250% of normal across our southern
deserts. Shower and thunderstorm chances continue across mainly
Mohave County on Monday although a few cells could develop further
west into southern and eastern San Bernardino County and southern
Nevada. No relief from the heat on Monday with temperatures
forecast to be around 7 or 8 degrees above normal with higher
humidity making it feel a little stickier.

Widespread moderate Heat Risk will continue across the region
Sunday and Monday. There are no official heat-related products in
effect but regardless, the same types of precautions should be
followed to protect yourself from heat exhaustion and heat stroke.
Limit time in the sun during the hottest part of the day, stay
hydrated, wear loose, light colored clothing, and do not leave
children or pets in the car for any amount of time.

.LONG TERM...Tuesday through Friday.

An extended period of hot weather is the main story though much of
the week as an expansive area of high pressure sets up and holds
across the Desert Southwest as is typical for this time of year.
There are indications the high flattens a little Thu-Fri in response
to a trough swinging across the Intermountain Region. The latest
NBM indicates daily high temperatures across the Mojave Desert
zones will generally be in the 108-112 degree range which is
several degrees above normal...but not uncommon for late June. The
official forecast for Las Vegas holds at 108-109 for most days
except peaks at 110 on Wednesday. Overnight lows will be in the
mid to upper 80s. While this is hot, the latest HeatRisk grids
have backed off slightly on indicating areas of major HeatRisk
(level 3) for Tue-Wed and mainly keep moderate across most of the
region.

&&

.AVIATION...
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For Harry Reid...Southerly winds up to 7 knots early
this morning will weaken becoming light and variable. Several hours
of southeast wind possible betwe.UPDATE...Moisture has arrived in Las Vegas with 0.97" inches of
precipitable water (PW) on this morning`s sounding. That`s a 0.57"
increase from yesterday`s 12Z sounding and 0.50" above average for
this time of year. Despite the anomalous PW on this morning`s
sounding the lower levels of the atmosphere remain dry as indicated
by the inverted V-shape in the lower levels of the sounding. This
inverted V-shape in the lower levels of the sounding combined with
1,900+ J/kg of DCAPE point towards an increased risk of strong
outflow winds from any storms that develop this afternoon. Speaking
of afternoon storms, the latest HiRes guidence has convection
beginning to fire in Mohave County around 18/19Z (11 am/12 pm PDT)
with southern Clark County, eastern Lincoln County, and portions of
San Bernardino County joining the party a few hours later. As was
previously mentioned, winds will be one of the primary threats with
today`s storms along with periods of moderate to heavy rain and
lightning.en 16Z and 20Z becoming more
southerly through the afternoon and evening. The one thing that
could complicate the winds would be outflow from isolated
thunderstorms that develop south and east of the terminal over the
McCullough Range. Temperatures are forecast to reach 100 degrees
around 10 am and remain above 100 degrees through at least 10 mph
this evening.

For the rest of southern Nevada, northwest Arizona and southeast
California...Generally south to southwest winds across southern
Nevada, lower Colorado River Valley and northwest Arizona. However,
isolated to scattered thunderstorms are expected primarily along and
southeast of Interstate 15, likely producing outflows which will
disrupt the winds and possibly cause poor visibility in blowing
dust. These storms will also produce isolated ceilings below 8000
feet with associated terrain obscuration. Farther west in the
western Mojave Desert and Owens Valley, expect similar winds as
yesterday, west-northwest at KDAG with afternoon gusts developing 20
to 25 knots, and at KBIH southerly direction with gusts 20 to 25
knots.
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&&

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

&&

$$

UPDATE...Stessman
SHORT TERM...Salmen
LONG TERM...Adair
AVIATION...Pierce

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