527
FXUS65 KVEF 081922
AFDVEF

Area Forecast Discussion
National Weather Service Las Vegas NV
1222 PM PDT Mon Jul 8 2024

.SYNOPSIS...Historic heat wave will persist across the Desert
Southwest through the week with numerous daily and all-time records
at jeopardy. This weekend, monsoonal moisture will usher into the
region, which will allow temperatures to gradually moderate as
precipitation chances increase across northwestern Arizona.

&&

.DISCUSSION...Today through Sunday.

Yesterday, 6 locations experienced record daily maximum
temperatures with 3 locations breaking or tying their all-time
maximum temperature records! Las Vegas broke their all-time record
of 117 - which had occurred 5 times - with 120 degrees. Bishop,
Barstow- Daggett, and Desert Rock all tied their all-time records
with 111, 118, and 114, respectively. Historic temperatures will
continue through the week as afternoon high temperatures range 10
to 15 degrees above seasonal averages.

The Excessive Heat Warning for much of the area including Heat
Advisories for the eastern Sierra slopes, White Mountains (Inyo),
Sheep Range (Clark), and Spring Mountains (Clark) have all been
extended to include Friday as well, as HeatRisk values remain
elevated into the Major and Extreme levels across the region. This
extension into Friday will result in a tie for the longest duration
Excessive Heat Warning for both Las Vegas and for Death Valley with
10 days. This has occurred 2 other times in 2022 and in 2017.

As mentioned in the previous discussion, afternoon highs today may
range a couple of degrees cooler than yesterday, as we experience a
very modest drop in 500 mb heights and marginal cold air advection.
Regardless, all 7 climate sites remain at risk of breaking or tying
their daily temperature records again today, as temperatures will
still be stifling.

20 lightning strikes were noted in the southern Sierra yesterday as
a result of pop-up convection. The HRRR and the FV3 support
convection returning to northern Inyo County into Esmeralda County
this afternoon, with strong gusty winds and frequent lightning
possible. Due to the dry low levels, heavy rain and flash flooding
are not expected.

The strong area of high pressure over the region will remain
directly over southern Nevada through the week before it slowly
meanders eastward heading into the weekend. This shift to the east
will exhibit a classic monsoon pattern, as it will allow moisture
to flux northward up the Colorado River Valley. Both the GEFS and
ECMWF ensemble means indicate over 1.00" of PWAT in Las Vegas by
Sunday. As a result of this moisture, temperatures will be allowed
to moderate, with the stretch of our heat-related headlines
coming to a close.

Precipitation amounts are currently confined to northwestern Arizona
and far southern Nevada where slight PoPs exist each afternoon
Saturday through Monday, though this forecast may be somewhat
inflated by model climatology. Will continue to assess the risk of
thunderstorms in the forecast area as we move through the week.

&&

.AVIATION...For Harry Reid...Northeast breezes of 6-9 knots through
the early afternoon, with occasional gusts to 15 knots. 20% chance
of sustained winds of 10+ knots. By late afternoon, winds weaken and
become more southeasterly, possibly becoming variable in direction.
After sunset, winds return to a typical southwest direction and
persist through the night. Temperatures remain above 100 degrees
through 07z, peaking this afternoon between 22z-00z around 115
degrees. Mostly clear skies with just a cloud or two possible over
the Spring Mountains.

For the rest of southern Nevada, northwest Arizona and southeast
California...Generally light and diurnal winds at the Las Vegas
Valley sites today, with occasional gusts up to 15 knots possible
this morning. At KBIH, light and variable conditions until breezy
west winds arrive around 00z. FEW-SCT mid-level clouds, primarily
over the high terrain. Cannot rule out a stray vicinity shower/storm
north of the airport this afternoon as rain chances stand around
20%. Light northwest breezes anticipated overnight. At KDAG, breezy
west winds arrive around 01z-02z with gusts of 20-25 knots. In the
Colorado River Valley, north winds with gusts of 15-25 knots this
morning and afternoon. Winds subside around sunset, becoming light
and variable late tonight. Very hot conditions persist, with
afternoon temps largely in the 110-120 range.

&&

.CLIMATE...Numerous climate locations have a forecast high
temperature and/or forecast warm low temperature within 3 degrees of
the daily record.

The table below shows the daily record maximum temperature and the
year the record was last set. An asterisk (*) denotes which records
are in jeopardy (within 3 degrees of the forecast).

MAX       MON, JUL 8   TUE, JUL 9  WED, JUL 10  THU, JUL 11
             Record(Yr)   Record(Yr)  Record(Yr)   Record(Yr)

Las Vegas     114(2021)*  116(2021)*  117(2021)*    116(1959)*
Bishop        109(2021)*  108(2021)*  111(2021)*    109(2021)*
Needles       120(2017)*  120(2021)*  122(2021)*    120(2020)*
Daggett       114(2021)*  113(2021)*  118(2021)*    117(2021)*
Kingman       108(2017)*  111(2021)*  111(2021)*    110(1961)*
Desert Rock   108(2017)*  111(2021)*  111(2021)*    114(2021)*
Death Valley  128(1913)*  130(2021)*  134(1913)     129(1913)*

The table below shows the daily record warm minimum temperature
and the year the record was last set. An asterisk (*) denotes
which records are in jeopardy (within 3 degrees of the
forecast).

WARM MIN      MON, JUL 8  TUE, JUL 9  WED, JUL 10  THU, JUL 11
              Record(Yr)  Record(Yr)  Record(Yr)   Record(Yr)

Las Vegas     92(2017)*   93(2021)*   94(2021)    91(2012)*
Bishop        70(1991)    72(1975)    71(1985)    70(2013)
Needles       95(2018)    95(2021)    98(2021)    96(2021)
Daggett       84(2021)*   85(2017)*   88(2021)    90(2021)
Kingman       84(2014)    82(2017)    79(1913)*   81(2021)*
Desert Rock   81(2021)*   86(1985)    82(2021)*   87(2021)
Death Valley  105(1921)   104(2021)   100(1927)* 105(1920)


&&

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

&&

$$

DISCUSSION...Soulat
AVIATION...Woods

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