445
FXUS65 KREV 102057
AFDREV

Area Forecast Discussion
National Weather Service Reno NV
157 PM PDT Fri May 10 2024

.SYNOPSIS...

A warming trend continues across the Sierra and western Nevada
with above average temperatures through next week. Isolated
showers and thunderstorms may make a return to the Sierra this
afternoon, with a slight increase in thunder chances mainly near
the Sierra from Sunday through Tuesday. However, most areas will
remain dry for the upcoming week.

&&

.DISCUSSION...

Key Points:

* Warming trend will continue through this weekend, with highs
  10-15 degrees above average from Sunday through late next week.

* Isolated shower/thunder chances for today limited to southern
  Mono-Mineral counties, with no thunder expected Saturday.

* Chances for afternoon showers and thunderstorms return mainly
  near the Sierra for Sunday-Tuesday.

The lingering effects of an elongated upper low over the Great
Basin continue to show up with east flow persisting across much of
the region, and scattered cumulus buildups mainly in southern
Mono-Mineral counties. Most of the guidance leaves open a small
10-15% chance for isolated showers and perhaps a couple of
lightning strikes in these areas between 3-8 PM.

Otherwise as this low finally departs to the east tonight through
Sunday morning while a ridge of high pressure builds into CA,
this period will be free of any shower or thunderstorm chances.
Temperatures will warm up several degrees on Saturday, reaching
80 degrees in some western NV valleys and near 70 degrees for
Sierra communities.

By Sunday afternoon, increased heating along with weak terrain
convergence along the Sierra crest will bring back isolated
shower/thunder chances mainly near the Sierra (near 20% chance)
while a few short lived cells could also develop across northeast
CA and far western/northwest NV during the late afternoon. Anyone
planning Sierra backcountry activities should keep extra
attention to the sky Sunday afternoon and have access to shelter
or a vehicle if/when storms develop.

Monday brings a bit higher chance (up to 25%) for afternoon
thunderstorms in the eastern Sierra south of Tahoe, and western
NV south of US-50 and west of US-95, due to a weak upper
disturbance extending from an upper low off the southern CA
coast. This system is projected to drift southward by Tuesday,
limiting isolated thunder chances to southern Mono County. For the
remainder of next week, the potential for afternoon thunder is
low (less than 10%), although subtle small scale features within
the warm air mass could eventually be resolved by higher
resolution guidance. Therefore we can`t completely rule out a
couple of cells forming during the mid-late afternoon especially
near higher terrain.

From Sunday through late next week, confidence is high for daytime
temperatures generally 10-15 degrees above average, bringing highs
of lower-mid 80s to lower elevations and lower-mid 70s for Sierra
communities. Slight fluctuations of these temperatures and
resulting wind directions remain possible for mid-late next week,
as ensemble guidance scenarios vary from a flatter zonal flow
aloft to a more amplified ridge centered over the Pacific
Northwest. MJD

&&

.AVIATION...

E-NE wind gusts of 15-25 kts will diminish after 00Z, with
lighter winds prevailing through Saturday. By Sunday afternoon a
modest zephyr breeze brings more typical SW-W winds with gusts
15-20 kt across the main terminals.

VFR conditions will prevail over the main terminals for the
majority of the upcoming week. Only exception may be the return
of patchy FG/FZFG to KTRK by early Sunday AM, and each morning
into early next week.

As for precip/thunder chances, for today only KMMH has a modest
10-15% chance for a cell coming near the terminal thru 01Z. Then
after a dry Saturday, the next chance (15-20%) for showers/thunder
returns to the Sierra/Tahoe area terminals Sunday afternoon, then
the highest potential (near 25%) shifts to KMMH Monday afternoon.
Main impacts expected to include isolated lightning, brief
rainfall with lower CIGS, and outflow wind gusts up to 30 kt.

&&

.REV Watches/Warnings/Advisories...
NV...None.
CA...None.
&&

$$