953
FXUS65 KVEF 010311
AFDVEF

Area Forecast Discussion
National Weather Service Las Vegas NV
811 PM PDT Sun Jun 30 2024

.SYNOPSIS...Hot and breezy conditions will continue across most
of the region today. Monsoonal moisture will move back into
northwest Arizona today, bringing slight chances for thunderstorms
in eastern Mohave County through the middle of the upcoming week. A
strong ridge of high pressure will build Wednesday through the
Independence Day weekend, with temperatures climbing to dangerous
levels for several days.
&&

.UPDATE...Winds continue to decrease this evening as the sun sets,
thus the Red Flag Warning for Lincoln County has been allowed to
expire at 8 PM. With today`s high and low temperatures pretty much
locked in at this point, we can do a little number crunching to get
June`s numbers for our climate sites. Long story short, it was a hot
one. All 7 climate sites recorded a top-5 warmest June, with Las
Vegas shattering its June records. Coming back to the forecast,
we`ll be monitoring the potential for some showers/storms creeping
into southern Mohave County tonight. Should convection reach this
area, the main concerns would be isolated heavy downpours, but the
chance of flash flooding is less than 10%. Rain chances through mid-
week will be confined to Mohave County as the edge of monsoonal
moisture noses in. Otherwise, our forecast area remains dry and hot,
with temperatures running 3-6 degrees above normal. During the 2nd
half of the week, heat becomes more excessive as high pressure
builds. Many locations will likely be flirting with daily records,
and it`s possible a few all-time highs could be challenged. Stay
cool out there.
&&

.SHORT TERM...tonight and Through Tuesday Night.

Will need to watch the moisture pool that is situated over the
Sonoran Desert this afternoon and how it may influence the weather
in southern Mohave County tonight. The latest HREF and hi-res models
do develop showers and thunderstorms that might rotate into
southeast portions of Mohave County tonight. This is when HREF shows
30%-40% probabilities for SB CAPE over 500J/kg and a brief increase
of PWATs to 1.0-1.5 inches. The probability for dewpoints over 60F
also increases to 80%-90% this evening and tonight in areas south of
I-40 in Mohave County. Based on this change in the atmosphere since
the previous forecast and ensemble trends, ensured there was a
mention of precipitation tonight through the area. Focused on the
far southeast corner of Mohave County, will monitor trends and model
output to see if precipitation chances need to be brought further
west tonight. Even with all this, chances will be low (30% or less)
and impacts would be limited. Lightning is noted on HRRR models
tonight and with some midlevel instability seen on model soundings
in the area, lightning will be the main threat. Gusty outflow winds
and brief heavy rain will also be possible. Will need to watch for a
potential outflow winds pushing in from convection that develops
further south. A few hi-res wind models do show a south to southeast
outflow moving through southern Mohave County this evening and
tonight, but no impactful winds were noted.

Across the rest of the region, it will remain dry. Breezy winds this
evening will subside tonight but should pick up again Monday
afternoon. Winds Monday afternoon will be slightly lower than
today;s winds as the upper level system that brought breezy winds to
the area lifts north.

Most of the region will remain dry through Tuesday night. There is a
low chance for isolated showers and thunderstorms in far eastern
Mohave County at the moisture that may push in tonight lingers over
that area. PWATs start to decrease Monday afternoon through so any
precipitation will be very isolated and impacts will be limited. By
TUesday, PWATs drop enough that precipitation is not expected across
the region including Mohave County. Temperatures will begin an
upward climb on Tuesday as high pressure builds back into the region
as the shortwave lifts away. Monday`s high temperatures will be
similar to today, then on Tuesday it will warm a few degrees and a
moderate heatrisk is expected in most locations outside of the
Southern Great Basin. Anyone with outdoor plans or who are sensitive
to the heat should be aware of the heat on Tuesday, drink extra
water and take breaks in cooler areas.

.LONG TERM...Wednesday through Saturday.

The extended outlook continues to point to an excessively hot period
setting up for a large portion of our area midweek and beyond.
Wednesday looks like the start of an extended period of dangerously
hot conditions with multiple days of near record or record heat
forecast across the Western Mojave Desert including the Barstow
area, across much of Inyo and central and southern Nye counties
including Death Valley National Park, Pahrump, and Beatty, and in
the Las Vegas Valley. Major to extreme Heat Risk is forecast in
these areas through the period where temperatures could approach,
tie, or even break daily heat records. Probably the biggest forecast
challenge will be in deciphering the daily fluctuation in Heat Risk
levels across areas generally south of the I-15 and how this
information will be best relayed to emergency management officials
and to the public. Moderate to major Heat Risk is indicated
throughout the period with Friday standing out as the peak day
featuring widespread high Heat Risk.

This magnitude of heat is dangerous to everyone and proper safety
precautions are recommended including limiting time outdoors and
staying hydrated.
&&

.AVIATION...For Harry Reid...South to southwest breezes are expected
through the afternoon, with gusts over 20KT expected and a moderate
probability (60% chance) for gusts over 25KT between 20Z-02Z today.
Winds will decrease this evening with gusts ending around 03Z-04z.
Moderate confidence in the overnight wind speed forecast. Will be
southwest much of the night before transitions to the south Monday
early morning, however its a 50% chance for winds to remain elevated
at 8-10KT through the night. Kept the elevated winds in through the
night however they may be lighter overnight, especially after
09Z.1031 High confidence that winds increase again Monday morning
after sunrise with the probability for wind speeds over 10KT jumping
back to 80% or higher at 15Z. South to southwesterly breezes are
expected again Monday afternoon with wind speeds and gusts slightly
lower than today`s winds. No significant clouds or weather are
expected through the forecast period. 100F temperatures are likely
19Z to 02Z today and Monday.

For the rest of southern Nevada, northwest Arizona and southeast
California...Souther to southwest winds will gust 20-25KT across
much of the region this afternoon. Winds at KDAG will favor a more
westerly direction but like likely (80% chance) still see gusts over
20KT after 21Z. KBIH will follow typical diurnal directional
patterns through much of the afternoon until a west push moves in
around 00Z. Gusts up to 20KT are possible (60% chance) with the west
winds at KBIH. Winds will decrease this evening and should follow
typical wind patterns overnight. Elevated north to northeast winds
are possible at KBIH 03Z-06Z before typical northwest winds at 8KT
or less set up for the overnight period. Will need to watch for
outflows coming out of south-central Arizona that could push through
southern Mohave County into KEED and KIFP after 09Z, which would
turn winds southeast and bring gusts to around 20KT. No significant
clouds or weather are expected through the forecast period.

&&

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

&&

$$

UPDATE...Woods
SHORT TERM...Nickerson
LONG TERM...Salmen
AVIATION...Nickerson

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