Severe Thunderstorm Warning 11, NWS Reno, NV

Area Forecast Discussion
National Weather Service Reno NV
1228 PM PDT Fri Jul 25 2025

.KEY MESSAGES...

* Thunderstorm activity continues today through Sunday. Potential
  impacts include heavy downpours and flooding, strong outflows,
  small hail, and lightning.

* Cooler than normal temperatures expected for the rest of the
  week and the weekend.

* A gradual warming and drying trend returns early next week,
  bringing highs up to near or slightly above normal. Showers
  linger into early week.

&&

.DISCUSSION...

Today's setup is going to provide plenty of moisture and instability
to kick up some afternoon storms, similar to yesterday, but with
higher chances and more widespread coverage. The placement of the
low circulation over central California is creating upper level
flow that will induce faster storm motions toward the north over
the Sierra for storms that initiate south of US-50. To the north
of the Tahoe Basin, storm motions will be slower and move to the
west, allowing for more opportunity for heavy raining storms to
induce flooding. Reports from yesterday's storms rolling through
left 0.25-0.50 inches of rain for some locations. Areas that have
not yet dried out are expected see more showers and storms today,
so we are watching for flooding potential, especially over recent
burn scars and flood prone areas. Storms may produce more rain
today, with PWAT yesterday around 0.6 inches and today's checking
in higher at 0.8 inches. Similar to yesterday, other hazards are
to include gusty outflow winds, frequent lightning, and small
hail. Keep your eyes to the skies this afternoon if you have
outdoor plans today, and remember, When Thunder Roars, Go Indoors!
Showers that initiate over/near lakes could cause increasing wave
heights as the gusty outflows have been producing winds of 30-40
mph.

Saturday, we stick with our scheduled program of widespread storms
with chances ranging 30-60%. Saturday's showers will have shifted
slightly eastward, so leeside valleys that remain dry today have
another opportunity to catch a few drops in their rain gauges.
Similar to today's storms, the risks will still include heavy rain,
flooding, frequent lightning, small hail and gusty outflow winds.

Shower and storms stick with us for Sunday, as the slow-moving low
circulation waits to be swept eastward by the upper level trough
that will drop southward along the Pacific Northwest coast as it
deepens and intensifies. This feature currently is moving off the
Alaskan coast into the Gulf of Alaska, and will become more
influential as it draws nearer. Chances for Sunday drop to around 15-
35%, with the greatest chances south of the Tahoe Basin, along US-
50. In fact, the influence will continue through early week as
showers appear in long range guidance well into midweek. Around the
midweek timeframe, potential develops for some high-based
thunderstorms that could produce dry lightning. Warming
temperatures early next week will help to support instability as it
increases along the Oregon border in to NE California and NW Nevada.

HRICH

&&

.AVIATION...

* VFR conditions this morning will give way to MVFR conditions for
  some terminals as afternoon storms return to the region. Be
  aware of rapidly changing conditions as storms form, including
  LLWS, turbulence and mountain obscuration due to heavy rains.
  Showers today arrive in earnest around 21z, although some
  showers could develop as early as 20z. Storms should wrap up
  around 03z or until sunset, with the later showers hanging
  around Tahoe basin terminals KTVL and KTRK. Chances today around
  40-60% for all terminals.

* Storms return Saturday, with similar chances, timing and hazards.

 HRICH

&&

.FIRE WEATHER...

* Widespread thunderstorm chances today and Saturday, with chances
  ranging 30-60%. Humidity will remain elevated through Saturday,
  however a lightning strike outside of the wet cores of storms may
  ignite receptive fuels. Frequent lightning is expected through
  Saturday.

* Sunday, lowering relative humidity at the surface along with
  instability aloft will provide an environment that could produce
  dry lightning. HRICH

&&

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

&&

Special Weather Statement
National Weather Service Reno NV
131 PM PDT Fri Jul 25 2025

CAZ071-252100-
Lassen-Eastern Plumas-Eastern Sierra Counties CA-
131 PM PDT Fri Jul 25 2025

...A STRONG THUNDERSTORM WILL IMPACT PLUMAS COUNTY THROUGH 200 PM
PDT...

At 131 PM PDT, Doppler radar was tracking a strong thunderstorm near
Grizzly Campground, or 7 miles northwest of Beckwourth, moving
northwest at 5 mph.

HAZARD...Wind gusts up to 40 mph and nickel size hail.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around
         unsecured objects. Minor hail damage to vegetation is
         possible.

Locations impacted include...
Beckwourth, Grizzly Campground, Lake Davis, Mohawk Vista, Lightning
Tree Campground, Grasshopper Flat Campground, and Cromberg.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

If on or near Lake Davis, get out of the water and move indoors or
inside a vehicle. Remember, lightning can strike out to 10 miles
from the parent thunderstorm. If you can hear thunder, you are close
enough to be struck by lightning. Move to safe shelter now! Do not
be caught on the water in a thunderstorm.

&&

LAT...LON 3991 12034 3980 12064 3996 12078 4010 12043
TIME...MOT...LOC 2031Z 151DEG 5KT 3992 12053

MAX HAIL SIZE...0.88 IN
MAX WIND GUST...40 MPH

CJ

Special Weather Statement
National Weather Service Reno NV
141 PM PDT Fri Jul 25 2025

CAZ072-073-NVZ003-252115-
Greater Lake Tahoe Area CA-Mono CA-Greater Reno-Carson City-
Minden Area NV-
141 PM PDT Fri Jul 25 2025

...A STRONG THUNDERSTORM WILL IMPACT NORTHERN MONO...ALPINE AND
DOUGLAS COUNTIES THROUGH 215 PM PDT...

At 141 PM PDT, Doppler radar was tracking a strong thunderstorm 8
miles west of Coleville, moving north at 15 mph.

HAZARD...Wind gusts up to 40 mph and nickel size hail.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around
         unsecured objects. Minor hail damage to vegetation is
         possible.

Locations impacted include...
Topaz Lake, Coleville, Woodfords, Alpine Village, Mesa Vista,
Junction CA 89 And CA 4, Junction U.S 395 And CA 89, Indian Creek
Campground, Holbrook Junction, Monitor Pass, Turtle Rock Campground,
Indian Creek Reservoir, Alpine County Airport, Topaz Lake Campground,
and Markleeville.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

Persons in campgrounds should consider seeking sturdy shelter until
this storm passes.

&&

LAT...LON 3853 11978 3855 11981 3856 11981 3880 11983
      3877 11941 3850 11952
TIME...MOT...LOC 2041Z 188DEG 14KT 3860 11966

MAX HAIL SIZE...0.88 IN
MAX WIND GUST...40 MPH

CJ