000
FXUS65 KREV 130938
AFDREV

Area Forecast Discussion
National Weather Service Reno NV
238 AM PDT Thu Aug 13 2020

.SYNOPSIS...

Drier air will keep thunderstorms at bay today with typical
westerly afternoon breezes expected. Chances for thunderstorms
return Friday and persist into next week. A warm up is on track,
with hot temperatures for the weekend into next week.

&&

.SHORT TERM (through Saturday night)...

Very dry air remains in place across the region this morning with
excellent radiational cooling leading to some temps dropping into
the 30s in the Sierra. Enjoy the cooler weather while we can,
because we are looking at a major warming trend going into the
weekend. A strong ridge begins expanding across the Desert
Southwest with high temperatures returning to upper 90s to low
100s for lower valley locations. We`ll start to see this trend
the start of the weekend, but the ridging really doesn`t peak
until the early part of next week. Please see the long term
section below for additional details.

Moisture will begin to seep northward under the ridge with
thunderstorms returning the forecast by Friday, and likely
continuing into next week. Storms may begin as a hybrid of wet and
dry, which could bring concerns for new fire starts, but should
transition to wetter based on ensemble PWAT guidance. The other
concern right now is for cloud cover and increased moisture to keep
the overnight lows relatively mild with potential heat impacts to
sensitive populations. This is likely to be a bigger problem
going into next week. -Dawn

.LONG TERM...Sunday onward...

The biggest change was to take thunderstorms out of the forecast
next Wednesday and Thursday. Other than this, no large changes were
made to the long term forecast as both deterministic and ensemble
guidance continue to show well above average temperatures and
typical afternoon zephyr breezes for our region through at least the
middle part of next week.

A ridge currently over southern Arizona and New Mexico will begin to
build northward and amplify considerably through the early part of
next week. This translates to a warming trend with highs into the
upper 90s to near 100 degrees for western Nevada valleys and mid-to-
upper 80s in the Sierra Sunday through at least next Thursday.
Although these temperatures are well above normal (5 to 10 degrees
or so), only a few isolated records look possible. High level clouds
from decaying convection and remnant tropical moisture look to also
keep nights warmer than average, with lows close to 70 in some of
the lower elevations of western Nevada. Past next Thursday, some
ensembles are hinting at the strong ridge moving east and
weakening. However, there still is much uncertainty to determine
when temperatures will return to near normal.

As far as thunderstorm chances go, the potential exists each
afternoon/early evening Sunday through Tuesday mainly along the
Eastern Sierra and portions of western Nevada south of US 50 where
favored areas of moisture convergence look to take place along the
higher terrain. Minor variations in thunderstorm coverage could
occur on one or more of these days as smaller scale shortwave
impulses rotate around the periphery of the ridge over the Great
Basin. -Johnston

&&

.AVIATION...

Mostly clear skies expected today. The one exception may be around a
new wildfire, the Poodle Fire, which is located just west of the
Black Rock Desert. This may bring smoke/haze restrictions, but is
also dependent on how actively the fire burns.

Otherwise, anticipate typical westerly afternoon breezes from 1p-9p.
Thunderstorm chances will return to the Eastern Sierra/Western
Nevada Friday afternoon, likely continuing and possibly expanding in
coverage by the end of the weekend into the start of next week.
-Dawn

&&

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

$$

For more information from the National Weather Service visit...
http://weather.gov/reno