655
FXUS65 KREV 122113
AFDREV

Area Forecast Discussion
National Weather Service Reno NV
213 PM PDT Sun May 12 2024

.SYNOPSIS...

Isolated showers and thunderstorms will bring gusty outflow
winds, small hail and brief heavy downpours through early week
with best chances in the Sierra. Otherwise, it will be drier and
much warmer this week with temperatures more like early summer.
Streams will be running fast and cold! Exercise caution if
venturing out on area rivers.

&&

.DISCUSSION...

* THIS AFTERNOON/TONIGHT: Flat cumulus developing underneath upper
  ridge this afternoon with 12Z KREV sounding showing things
  capped. HREF and model soundings continue to show just enough
  instability along the Sierra and far northern areas for a 10-20%
  chance of showers and thunderstorms late in the afternoon and
  early evening. Otherwise, some brief clouds and WSW breezes this
  evening then light winds and clearing late evening/overnight.

* MONDAY/TUESDAY: Weak trough will swing through the northern
  Great Basin Monday and exit to the east Tuesday as a ridge
  begins to build into the West Coast. This should result in a bit
  more coverage to storms along the Sierra Monday afternoon and a
  better potential for a few storms to push off into far western
  NV (areas near and west of Hwy 89). Best coverage (20-30%
  chance) will be along the Sierra from South Lake Tahoe to Lee
  Vining and Mammoth Lakes. Farther north into the Reno area, we
  could end up just seeing some showers with gusty winds, but we
  went ahead and stretched the thunder potential a bit farther
  north. Small hail, gusty outflows up to 45 mph, brief downpours
  and lightning will accompany stronger cells. A drier northerly
  flow will push convection to the Sierra crest for Tuesday with
  most of the activity likely drifting to the west side.

* WEDNESDAY TO FRIDAY: Drier and warming up some more. High
  temperatures will climb well into the 70s Sierra and 80s for
  lower valleys with a 30-50% chance for some warmer valleys
  topping 90 degrees Thu/Fri! This is 15+ degrees above average
  and more typical of early Summer. Stream flows will be on the
  increase due to the warmer temperatures and increased snowmelt.
  So if you have plans to be near area streams, be prepared for
  fast and cold waters.

* NEXT WEEKEND: Ensemble clusters point to a general trough and
  cooling. There is a lot of model spread, so confidence in how
  these pattern change will evolve remains low. If you have plans
  next weekend, keep an eye to the forecast and be prepared for an
  uptick in wind (as early as Friday afternoon) as well as a
  potential for showers/storms.

Hohmann

&&

.AVIATION...

* 10-20% chance of thunderstorms at Sierra terminals late this
  afternoon/early evening, increasing to 20-30% chance Sierra and
  spreading into KRNO-KCXP-KMEV Monday afternoon (10-20% chance).
  Gusty/erratic outflow winds to 35-40 kts and lightning will be
  the main impacts although some small hail cannot be ruled out.

* Storms Tuesday will be limited mainly to the Sierra crest south
  of Lake Tahoe, then dry and very warm Wed-Fri with a return to
  afternoon WSW breezes Friday ahead of a weak trough/front.

Hohmann

&&

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

$$