Flash Flood Warning 18, NWS Las Vegas, NV

113 
WGUS75 KVEF 220845
FFSVEF

Flash Flood Statement
National Weather Service Las Vegas NV
145 AM PDT Mon Jul 22 2024

AZC015-221015-
/O.CON.KVEF.FF.W.0018.000000T0000Z-240722T1015Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Mohave AZ-
145 AM MST Mon Jul 22 2024

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 315 AM MST EARLY THIS 
MORNING FOR WESTERN MOHAVE COUNTY...

At 145 AM MST, Doppler radar indicated thunderstorms producing heavy 
rain in Archibald Wash at Pierce Ferry Road have weakened. However, 
flash flooding will continue in Archibald Wash as runoff continues 
to move downstream toward Stockton Hill Road.

HAZARD...Life-threatening flash flooding. Thunderstorms producing
         flash flooding.

SOURCE...Radar.

IMPACT...Life-threatening flash flooding of low-water crossings,
         creeks, normally dry washes and roads.

Some locations that will experience flash flooding include...
  Pierce Ferry And Antares Roads.

This includes the following highways...
	Pierce Ferry Road between mile markers 16 and 22.
	Stockton Hill Road between mile markers 38 and 43.
	Antares Road between mile markers 31 and 32.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Turn around, don't drown when encountering flooded roads. Most flood 
deaths occur in vehicles.

&&

LAT...LON 3577 11411 3575 11411 3573 11410 3572 11410
      3570 11410 3570 11412 3569 11416 3570 11419
      3573 11420 3576 11421 3577 11422 3579 11414
      3578 11412

FLASH FLOOD...RADAR INDICATED
FLASH FLOOD DAMAGE THREAT...CONSIDERABLE

$$

BKP

993 
WGUS75 KVEF 221010
FFSVEF

Flash Flood Statement
National Weather Service Las Vegas NV
310 AM PDT Mon Jul 22 2024

AZC015-221020-
/O.EXP.KVEF.FF.W.0018.000000T0000Z-240722T1015Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Mohave AZ-
310 AM MST Mon Jul 22 2024

...FLASH FLOOD WARNING WILL EXPIRE AT 315 AM MST EARLY THIS MORNING 
FOR WESTERN MOHAVE COUNTY...

The heavy rain has ended. Flooding is no longer expected to pose a 
threat. Please continue to heed remaining road closures.

&&

LAT...LON 3577 11411 3575 11411 3573 11410 3572 11410
      3570 11410 3570 11412 3569 11416 3570 11419
      3573 11420 3576 11421 3577 11422 3579 11414
      3578 11412

$$

BKP

Area Forecast Discussion
National Weather Service Las Vegas NV
825 PM PDT Sun Jul 21 2024

.SYNOPSIS...High pressure continues to meander across the Desert
Southwest, resulting in diurnal rounds of showers and
thunderstorms, and a continuation of extreme heat. This pattern
looks to hold through the majority of the upcoming week.

&&

.UPDATE...
Ongoing showers and thunderstorms will gradually wane into the
late evening and overnight hours. Activity has generally
underperformed compared to what many of the convective-allowing
models would suggest. The latest hi-res ensembles are a bit closer
to what is currently transpiring, showing widely scattered
activity struggling to persist much beyond about 11pm to midnight.
Still, a low probability of a few showers and a stray storm will
persist through the next few hours, mainly across the Las Vegas
Valley and portions of Mohave County in Arizona. The main
consideration from any storms has been gusty outflow winds as
storms collapse within a deeply mixed and hot environment. At
times, wind gusts have exceeded 40 mph, though the potential for
strong downdrafts will generally diminish as daytime heating is
lost further into the evening. Once activity ends, expect another
very warm night with lows generally in the 80s and 90s most areas.

&&

.PREV DISCUSSION...

.DISCUSSION...Today through Saturday.

Convection expected again this afternoon across the region. PWATs
range from 0.75 to 1.25" across the southern Great Basin and
northern Mojave Desert this afternoon, though instability is limited
with a 500 mb area of high pressure directly overhead. Instability
will rely on daytime heating with a convective temperature in Las
Vegas at 113 and orographic lift with storms favoring the higher
terrain. Storms that form in southern Nevada and southwestern Utah
will likely kick out strong outflow winds between 30 and 40 mph with
over 2000 J/kg of DCAPE. HRRR runs have been consistent since 24
hours ago in showing an outflow from afternoon storms in southern
Nevada pushing southward and riding the northerly steering flow into
eastern San Bernardino County and southwestern Mohave County this
evening. Convection is expected to form along this outflow as the
air moves into a region of CAPE values exceeding 1000 J/kg and PWATs
approaching 1.50". SPC has a Marginal Risk of severe thunderstorms
in the southern Colorado River Valley surrounding Needles and Lake
Havasu City to reinforce this forecast.

PWATs will range from 100 to 200 percent of average across the
region through the week, which will return chances of precipitation
to the forecast area each afternoon through Friday.

Friday through the weekend, there is good agreement that the area
will dry out with the approach of an upper-level trough that will
effectively squash the monsoonal high overhead. ECMWF ensemble
members show a stark drop in PWATs between Thursday afternoon and
Saturday afternoon.

In addition to moisture, above-average temperatures will persist
through the work week. There is an Excessive Heat Warning out for
the Mojave Desert including Las Vegas, Mesquite, Pahrump, Laughlin,
Lake Havasu City, Kingman, Barstow, and Death Valley that originally
went through 9pm tonight. However, this Excessive Heat Warning has
just been extended through Wednesday at 11pm for all aforementioned
locations. Morning low temperatures will flirt with daily records
across all climate sites (for more details, see the CLIMATE section
below), which will result in minimal relief. Additionally, monsoonal
moisture in place will result in hot and muggy conditions - rather
than hot and dry. Despite temperatures being cooler than experienced
a few weeks ago when several climate sites across our forecast area
observed all-time hot temperatures, it is likely that conditions
this week will feel worse due to the increased humidity. Moisture
allows the air to retain heat for longer, which also means that
shaded locations will provide less relief than normal. HeatRisk
values are likely to underestimate this heat wave, as humidity is
not directly taken into account during the calculation. It is
important to take frequent breaks in air conditioning and drink
plenty of water and electrolytes.

There remains high confidence in an upper-level trough dropping from
the Pacific Northwest late-week into the weekend, which will work to
squash our monsoonal high. Temperatures will moderate and dry
conditions will return to the region.
&&

.AVIATION...For Harry Reid...Light easterly components should become
southwest around 23-00Z this afternoon. Showers and thunderstorms
building over the mountains to the north of the Las Vegas Valley
late this afternoon and evening may move to the south and impact the
terminal area with gusty northeast and erratic winds between 02Z and
05Z. Thunderstorm potential will diminish after 05z with loss of
daytime heating and once storm influences abate, winds will revert
to light overnight southwest components and easterly components
during late Monday morning into the afternoon. Thunderstorms will
likely develop again over the mountains west and north of the
terminal area Monday afternoon with the potential for erratic
outflow late in the afternoon and evening.

For the rest of southern Nevada, northwest Arizona and southeast
California...Isolated to scattered thunderstorms will develop this
afternoon/evening, bringing erratic winds, heavy rains and
lightning. The Las Vegas Valley airports and Lower Colorado River
Valley sites from IFP to EED and HII may see gusty and erratic winds
from thunderstorms between 02Z and 06Z this evening as storms move
toward the south. Showers and thunderstorms near KBIH and KDAG could
also impact those areas with gusty and erratic winds between 00Z and
03Z.
&&

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

&&

DISCUSSION...Austin
AVIATION...Salmen

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