969
FXUS65 KREV 222100
AFDREV

Area Forecast Discussion
National Weather Service Reno NV
200 PM PDT Tue Sep 22 2026

.KEY MESSAGES...

* Shower and isolated thunderstorm chances are in the forecast along
  the Oregon border and in the Sierra this afternoon.

* Warmer and generally dry conditions are expected through Thursday
  with temperatures 5 to 10 degrees above average.

* Increased winds may cause potential critical fire weather
  conditions within the region on Thursday and Friday with cooler
  temperatures returning going into the weekend.

&&

.DISCUSSION...

Current radar returns show isolated light showers already popping
up in the Sierra with satellite imagery showing cumulus clouds
developing along the OR border. These are the two portions of the
region that CAMs show the "best" chances (~15%) for light showers
this afternoon. Mineral and Lyon Counties as well as the Quad
Counties also have a low (5-10%) chance for these showers.
Portions of Mono County above 11 kft may see some light snow mixed
into the showers though not anticipating much accumulation if
any. The latest run of the HRRR also forecasts pockets of
CAPE values ranging up to 100-200 J/kg allowing for some rumbles
of thunder to occur within these showers (10% chance), though
thunderstorms that develop expect to be sub-severe today.
Precipitation chances expect to taper off around 8 PM this evening.

Model guidance shows low pressure over the NV/UT border today
traveling northeast allowing for a weak ridge to move over the CWA
by Wednesday. With this feature aloft, temperatures continue a
warming trend through midweek within the region. Daytime high
temperatures will climb to around 5-10 degrees above seasonal
normals by Wednesday and Thursday with NE CA and W NV valleys
topping out in the middle to upper 80s with Sierra communities in
the 70s. Dry conditions look to prevail through midweek as well.

On Thursday, forecast guidance shows an upper trough moving into
the Pac NW. This feature will cause the surface pressure gradient
to tighten at the surface, which allows for an increase in winds
on Thursday (gusts up to 25-30 mph). The latest run of the NBM
highlights a 30-50% chance of 35+ mph gusts in Northern Washoe
County and the adjacent portions of NE CA, which would allow for
critical fire weather conditions. Models then show a dry, cold
front associated with the east-moving Pac NW trough passing
through the region on Friday. Not only will this cause
temperatures to begin a cooling trend, but it will also allow for
area winds to increase further with gusts of 30-40 mph and a
40-60% chance of gusts of 40+ mph. These winds would cause choppy
waters on area lakes and increased coverage for critical fire
weather. The latest SPC fire weather outlook highlights N NV right
now for the best potential for fire weather concerns. Sierra
ridge wind gusts up to around 60 mph are possible as well on
Friday. Please watch for forecast updates as they become available
especially if confidence in critical fire weather conditions
increases. Breezy winds are seen over the weekend with daytime high
temperatures drop around 5 degrees below seasonal averages. -078

&&

.AVIATION...

VFR conditions continue today and tonight for all area TAF sites.
Mostly dry conditions are expected though there is a 15% chance
for isolated light showers in areas near the OR border as well in
the Sierra between 22/21Z-23/03Z. There is a low chance (10% or
less) for a thunderstorm to occur within these showers. Area winds
are forecast to generally be west to northwest with gusts up to
around 15-20 kts through around 23/03Z before becoming light and
variable overnight. Dry conditions are favored through the end of
the week with increased winds expected by Thursday. -078

&&

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

$$