119
FXUS65 KREV 251928
AFDREV

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.

&&

$$