Flash Flood Warning 1, NWS Reno, NV

Area Forecast Discussion
National Weather Service Reno NV
1226 PM PDT Thu May 4 2023

.SYNOPSIS...

A spring weather system moving inland across California and Nevada
will bring a return of shower and thunderstorm chances today and
tonight. Additional weak weather systems will maintain cooler and
unsettled weather across the region into the first half of next
week. Afternoon breezes will strike back the next several days,
with stronger gust potential in the vicinity of thunderstorms.

&&

.DISCUSSION...

* Today: The upper level low continues to strike back at the Sierra
  and western Nevada this afternoon and evening with more widespread
  potential for showers (60-70% chance) and thunderstorms (20%
  chance). Showers are already forming along the Sierra crest early
  this afternoon and are projected to migrate northward across the
  Tahoe Basin and eastward across the Reno-Carson City areas through
  the early evening. Plan on a mix of rain/pellet/snow showers with
  snow levels around 6500-7000 feet. More widespread showers will
  persist for areas east of Highway 95 and for far northern Washoe
  county overnight with a mix of rain/pellet showers possible into
  Friday morning.

* Friday - Saturday: Showers will be lingering across Churchill and
  Pershing counties through Friday morning as the main low exits to
  the east. Shower coverage in general for the rest of the region
  will be more isolated in nature, but any showers that pop up could
  put down a quick burst of rain/snow. Best potential for showers
  will remain confined across the Sierra for Friday. The next in our
  march of quick-hitting lows arrives late Friday into Saturday,
  with a return of more widespread shower potential, especially for
  areas north of I80 and along the OR border.

* Generally, Sunday is still holding out to be our break in the
  weather for the weekend and into early next week before another
  compact fast-moving low sweeps into northern CA on Monday into
  Tuesday. We will stay closer to below average temperatures
  through early next week, but by midweek we could see some
  gradual warming as high pressure attempts to build in across the
  West.

-Edan

&&

.AVIATION...

*  The persistent upper level low off the CA coast will finally
   meander inland today into Friday, bringing renewed chances for
   showers and a 15-30% chance for thunderstorms across the region,
   decreasing to 10-15% on Friday.

*  The potential for rain/snow/pellet showers hovers across the
   Sierra, northeast CA, and western Nevada today with terrain
   obscuration likely. Showers will gradually migrate towards
   northern and central Nevada overnight into Friday. Showers will
   focus along and north of I-80 and east of US-95. There will still
   be chances for showers (10-15%) elsewhere across the Sierra and
   western Nevada, but more isolated. Light slushy accumulations at
   KTRK/KTVL are possible overnight, but totals would be less than
   an inch.

*  Breezy SW-W afternoon winds return today and each
   afternoon/evening through the weekend with gusts 15-25 kts at
   terminal sites. FL100 winds are forecast to shift from the SE to
   the W today with the westerly flow lasting into the weekend and
   periods of mountain wave activity.

-Edan

&&

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

Special Weather Statement
National Weather Service Reno NV
1257 PM PDT Thu May 4 2023

CAZ071>073-NVZ001>005-042115-
Lassen-Eastern Plumas-Eastern Sierra Counties CA-
Greater Lake Tahoe Area CA-Mono CA-Greater Lake Tahoe Area NV-
Western Nevada Basin and Range including Pyramid Lake NV-
Northern Washoe County NV-Greater Reno-Carson City-Minden Area NV-
Mineral and Southern Lyon Counties NV-
1257 PM PDT Thu May 4 2023

...Isolated Thunderstorms Over Western Nevada and Northeast
California Expected this Afternoon...

At 1250 PM, Doppler radar was tracking a thunderstorm near Carson
City, moving northwest at 10 mph. Additional isolated thunderstorms
are expected to develop over the region through the afternoon. Main
threats include strong winds in excess of 40 mph, dime-size hail,
brief heavy rainfall, and dangerous lightning.

Locations impacted include...
Reno, Carson City, South Lake Tahoe, Tahoe City, Graeagle, Kings
Beach, Plumas Eureka State Park, Gardnerville, Virginia City, Boca
Reservoir, Pyramid Lake, Incline Village, Blairsden, Doyle, Alpine
Meadows, Stampede Reservoir, Squaw Valley, Herlong, Chilcoot and
Sierraville.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

Storms that develop this afternoon may intensify, so be certain to
monitor local radio stations and available television stations for
additional information and possible warnings from the National
Weather Service.

&&

LAT...LON 4069 11959 3854 11891 3850 11975 3858 11985
      3869 11998 3881 12003 3885 12016 3920 12025
      3949 12044 3960 12046 3971 12063 3968 12068
      3971 12072 3991 12075 4019 12088 4024 12104
      4034 12106
TIME...MOT...LOC 1950Z 120DEG 10KT 3922 11988

MAX HAIL SIZE...0.50 IN
MAX WIND GUST...30 MPH

BW