Tecopa, California Weather Forecast Discussion

077
FXUS65 KVEF 271112
AFDVEF
Area Forecast Discussion
National Weather Service Las Vegas NV
412 AM PDT Sat Sep 27 2025
.KEY MESSAGES...
* Chances for isolated to scattered showers and thunderstorms will
  continue through the weekend across southern Nevada, northwest
  Arizona, and southeastern California.
* Moisture will gradually decrease next week as a low pressure
  system approaches West Coast, bringing breezier winds and
  helping cooler than normal temperatures hang around through the
  week.
&&
.DISCUSSION...through next Friday.
The low pressure system responsible for the showers and
thunderstorms of the past few days will continue to sit and spin
over southern California, southern Nevada, and western Arizona
through the weekend. This system, combined with above normal
moisture, will drive isolated to scattered showers and thunderstorms
across the region today and tomorrow. Moderate-to-heavy rain, flash
flooding, strong outflow winds, hail as big as 1 inch, and frequent
lightning will be hazards with any storms that develop. Storms will
begin to push into southern San Bernardino and Mohave Counties early
this morning with additional storm development spreading later in
the morning and into the afternoon as daytime heating gets going.
The greatest risk for flooding will be across southern San
Bernardino County into Mohave County where stronger storms will be
capable of producing 1.0+ inch per hour rain rates. Convection will
weaken after sunset, however, some areas will see weak, isolated
showers and thunderstorms continue into the overnight hours as the
low remains stationary to our south. Another round of storms is
expected on Sunday, but coverage will be less expansive as we find
ourselves on the back side of the low as it starts to exit the
region.
The low pressure system will begin its slow exit from the Desert
Southwest on Sunday, lifting out of the region on Monday as a trough
pushes into the Western US. This will result in breezy winds across
the region with isolated showers possible on Monday and Tuesday
across northwestern Arizona and the Great Basin as this system
pushes in. As we find ourselves under southwesterly flow aloft, we
will see moisture gradually scoured out. However, it is important to
note there remains some uncertainty regarding how quickly we will
dry out as it will depend on how much moisture from Hurricane Narda
in the East Pacific ends up getting advected into the area during
the second half of the week. Regardless of what happens with
moisture from Narda, the lower than normal 500 mb heights will allow
cooler than normal temperatures to stick around through the end of
the week.
&&
.AVIATION...For Harry Reid...For the 12Z Forecast Package...Outside
of convective influences, expecting light winds that follow typical,
daily patterns. However, another round of scattered showers and
storms are expected this afternoon and evening, with the best
chances between 21z and 03z. Storms will likely contain erratic and
gusty outflow winds, frequent lightning, and brief MVFR/IFR
conditions within heavy rain. Thunderstorm potential should wane
after sunset, but vicinity showers may linger into the night. Cloud
bases generally 8-12kft throughout the period, with SCT-BKN
conditions this afternoon and evening.
For the rest of southern Nevada, northwest Arizona and southeast
California...For the 12Z Forecast Package...Outside of convective
influences, expecting light winds that follow typical, daily
patterns. However, scattered showers and storms are likely today,
especially across the Mojave Desert during the daytime hours.
Already seeing some isolated convective activity in southern San
Bernardino County, and this should continue through the morning
before becoming more widespread in later today. Storms will likely
contain erratic and gusty outflow winds, frequent lightning, and
brief MVFR/IFR conditions within heavy rain. Thunderstorm potential
should wane after sunset, but isolated to scattered showers may
linger into the night. Cloud bases generally 8-12kft throughout the
period, with periods of SCT-BKN conditions.
&&
.SPOTTER INFORMATION STATEMENT...Spotters are encouraged to report
any significant weather or impacts according to standard operating
procedures.
&&
$$
DISCUSSION...Stessman
AVIATION...Woods
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NWS VEF Office Area Forecast Discussion