Mountain Pass, California Weather Forecast Discussion

815
FXUS65 KVEF 221233
AFDVEF
Area Forecast Discussion
National Weather Service Las Vegas NV
532 AM PDT Mon Sep 22 2025
.KEY MESSAGES...
* Low chance for showers and isolated thunderstorms in far southern
  Mohave County through the morning and afternoon, however impacts
  should be minimal.
* Precipitation chances linger each day through the upcoming week
  due to anomalous moisture and periodic disturbances moving
  across the region.
&&
.DISCUSSION...Through the Weekend.
Through the morning, radar showed light returns streaming through
southern Mohave County in response to a weak southwesterly upper
level jet ahead of an upper level low off the Southern California
Coast. Little to no rain was reported with these showers so far In
general, expecting scattered showers to continue through the morning
and afternoon as weak forcing sits over as modestly moist
environment. The better forcing and highest moisture will remain
outside of the forecast area though, so overall impacts and chances
for rain are low. Probabilities for over 0.10 inch of total rainfall
through today are 20% or less. HRRR and HREF do show some lightning
flashes this afternoon with the precipitation this afternoon in
southern Mohave County, so isolated thunderstorms are also possible
but would be limited in impacts as instability will remain low. By
this evening, hires models show any showers that do develop shifting
south and ending and a dry night is expected.
Looking ahead, the aforementioned low off of the California Coast
will remain the primary feature of concern, though uncertainty
regarding its evolution somewhat muddles the forecast. Anomalous
moisture (roughly 100-150% of normal) will remain over the region
ahead of this low, with any subtle shortwaves embedded in the
southwesterly flow aloft warranting at least a slight chance mention
of precipitation across the area each day through the upcoming week.
Ensembles continue to differ on the timing and trajectory of this
low as it eventually moves inland toward the latter half of the work
week, though once it finally translates eastward, precipitable water
values are progged to ramp up closer to 150-200% of normal. However,
uncertainty regarding its evolution as well as uncertainty regarding
how much moisture will be sapped by the windward side of the Sierra
lends to a lower confidence forecast. Regardless, the continued
presence of moisture will keep rain chances in the forecast, as well
as serve to keep temperatures near and below normal through the
forecast period.
&&
.AVIATION...For Harry Reid...For the 12Z Forecast Package...Light
and variable winds will persist through this morning before turning
easterly with sustained speeds under 8 knots after 18Z.  Typical
southwesterly winds will return after sunset this evening.  VFR
conditions will prevail through the TAF period, with SCT to FEW
clouds with bases around 15kft AGL through early evening, then
becoming SKC overnight.  No precipitation is anticipated in the Las
Vegas Valley, though a few isolated showers are possible well south
and east of the area along the Peach Springs corridor through 23Z.
For the rest of southern Nevada, northwest Arizona and southeast
California...For the 12Z Forecast Package...Winds across the region
will generally follow typical diurnal patterns through the TAF
period.   A band of light showers will continue moving across
southeastern San Bernardino County and central and southern Mohave
County into this afternoon.  VCSH has been included for KEED but
removed for KIFP.  Expect SCT to BKN skies with bases around 15kft
AGL near any showers.  Away from precipitation, VFR conditions will
prevail with FEW to SCT clouds through the afternoon, becoming SKC
from northwest to southeast overnight.
&&
.SPOTTER INFORMATION STATEMENT...Spotters are encouraged to report
any significant weather or impacts according to standard operating
procedures.
&&
$$
DISCUSSION...Nickerson
AVIATION...Planz
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NWS VEF Office Area Forecast Discussion