Cema, California 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

875
FXUS65 KVEF 191623
AFDVEF

Area Forecast Discussion
National Weather Service Las Vegas NV
923 AM PDT Thu Sep 19 2024

.SYNOPSIS...An area of low pressure will slowly move south along
the California coast today before turning inland and moving across
the southern Great Basin tomorrow. This will keep temperatures
several degrees below normal through Friday as well as bringing
the threat of precipitation to the region. Drier and warmer
conditions will return over the weekend and continue into next
week as a high-pressure ridge builds over the western US.

&&

.UPDATE...The latest infrared and water vapor satellite imagery show
the low pressure system spinning off the coast of central
California. This system will continue to dig south before moving
inland and through our forecast area on Friday. Precipitation today
will be limited to the Sierra crest, with the mountains expected to
block most of the moisture from spilling over into our forecast
area. The northern portion of the Owens Valley and White Mountains
of Inyo County have around a 25% chance of seeing light
precipitation from the little moisture that manages to get past the
Sierra. As the low pressure system moves through our forecast area
tomorrow, we will see more widespread precipitation chances across
the southern Great Basin and Mojave Desert. Precipitation chances
will linger into Saturday morning for the far eastern portions of
our forecast area as the low pressure system exits the region.

The biggest change to the short term forecast is the introduction of
a Marginal Excessive Rainfall Outlook (ERO) to San Bernardino and
Mohave Counties on Friday due to the convective potential as the
center of the cut-off low moves overhead. Essentially, pockets of
heavier precipitation will be possible with isolated thunderstorms
embedded within scattered showers. Outside of the addition
of this Marginal ERO, the current forecast remains on track with no
major changes necessary at this time.

&&

.SHORT TERM...Today through Saturday.

A deepening upper-level low-pressure center off the central
California coast this morning will drift southward towards SoCal
today before turning east and moving inland across our area on
Friday. Precipitation will remain limited to northern Inyo and
Esmeralda counties today as the Sierra will block most of the
moisture. Any moisture that is able to make it over the crest will
be light, and less than .15" of rain is expected around Bishop
through this evening. Snow is likely in the higher elevations of
the Sierra, where up to 4 inches may fall. However, snow levels
will generally be 9500 feet or higher, so significant impacts are
not expected.

As the low turns inland tonight and Friday, showers will spread
across the southern half of the region. Given the cold-core nature
of this system, there is the potential for weak convection to
develop as the center of the low passes across San Bernardino,
southern Clark, and Mohave counties, where CAPE values of 200-400
J/kg are forecast. However, moisture associated with this system
will continue to be limited, and the probability of any area
seeing .25" or more of rain is less than 30%. The chance of seeing
.50" of rain is nearly zero in all areas except for far eastern
Mohave County where there is a 10% chance of that occurring. It is
still not out of the question that the Spring Mountains could see
their first dusting of snow with this system Friday, although
snow levels will be around 10,000 feet, so any that does fall will
be limited to the highest peaks. The low will also deliver a
reinforcing shot of cooler air, keeping temperatures 10 to 15
degrees below normal through Friday. Winds are not expected to be
impactful with this system.

By Saturday, the low will shift east of the area, and only a few
isolated showers are expected across far eastern Mohave County
early in the day. As high pressure builds in the wake of the low,
most areas will see temperatures rebound back to near-normal
levels.


.LONG TERM...Sunday through Wednesday.

By Sunday morning, the low should be long gone, with rising
heights as high pressure noses in from the Pacific. There are
differences in the details as usual, but there is strong consensus
among the models that ridging will set up residence over the West
through (and beyond) the long term period. Thus, we can expect
dry weather and above normal temperatures areawide. The 01Z/19 run
of the NBM gives Las Vegas a 13% chance of reaching 100F on
Wednesday, with slightly higher chances later in the week.

&&

.AVIATION...For Harry Reid...Light winds expected overnight with
mostly clear skies.  Winds will remain light through the morning
hours before trending easterly after noon, then more southeasterly
in the mid-afternoon and evening hours with speeds of 8-12 knots.
Winds will shift back to the southwest after dark. Skies will remain
mostly clear through the period.

For the rest of southern Nevada, northwest Arizona and southeast
California...Generally light winds are favored through midday across
the regional TAF sites across the Mojave Desert and Colorado River
Valley, with more southeasterly winds of 8 to 12 knots filling in
during the afternoon and evening hours. Further north, SCT-BKN cloud
cover between 6-8kft AGL along with periodic shower activity is
expected near KBIH with localized mountain obscuration possible
through the period.

&&

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

&&

$$

UPDATE...Stessman
SHORT TERM...Planz
LONG TERM...Morgan
AVIATION...Outler

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