Technical Forecast Discussion

998
FXUS65 KREV 022005
AFDREV

Area Forecast Discussion
National Weather Service Reno NV
105 PM PDT Thu May 2 2024

.SYNOPSIS...

Warmer temperatures continue today through tomorrow, with periods
of showers likely along the Oregon border and breezy winds
creating choppy lakes this afternoon. Active weather returns
with a storm system bringing gusty winds along with valley rain
and mountain snow, with conditions slowly improving Sunday. Early
next week, a slow warming trend with low chances for
precipitation remain in the forecast.

&&

.DISCUSSION...

This afternoon`s radar depicts the showers along the Oregon border
as a weak trough swings across the Pacific Northwest. Plan on this
trend continuing through today, with chances for additional showers
dwindling through the afternoon.

* REST OF TODAY: Choppy waters will become a concern for anglers on
  Pyramid Lake due to gusty winds today. Sustained breezes up to 20
  mph with gusts as high as 30 mph are possible and will kick up
  choppy lake waters through this evening. Shower chances mentioned
  above will be greatest for Surprise Valley and far northern Washoe
  county, around a 30-55% chance.

* ENJOY FRIDAY: Our recent above average temperatures will settle in
  for one more day, with light winds making for a great day to get
  outdoors. But do not be fooled by this, the rest of the weekend
  will not be as ideal for outdoor recreation. A saying that comes
  to mind is, `make hay while the sun shines` for this Friday. Our
  only shot at any showers for Friday will be for the Sierra in Mono
  County, with only a slight (10-15%) chance for an afternoon
  shower.

* WEEKEND: Spring really can be fickle, and this weekend will be a
  great example of the variability we can see in this region
  during May. While this type of system would be less troublesome
  in January, the depth of the incoming trough and attendant cold
  air promises a noticeable change for May standards. Southwest
  winds will increase late Friday into the overnight, and by
  Saturday Sierra ridges will see gusts up to 90+ mph. Wind prone
  areas such as US-395 from Reno through Mono County and US-95 in
  Mineral County near Hawthorne could see gusts reaching 55 mph.
  There is a 40-60% probability for damaging winds from south of
  I-80 into Douglas, Lyon, Mineral and Mono counties. Blowing dust
  could be lofted by high winds near dry lake beds, creating
  reductions in visibility. High profile vehicle travel on north-
  south oriented roads may be difficult, while aviation travelers
  may experience bumpy plane rides. The winds will be followed
  closely by mountain snow showers and valley rains, although the
  Saturday night into Sunday timeframe will see snow levels
  crashing to 5,000-5,500 feet. The best chances for snow
  accumulations will be above 7000 feet, during the overnight
  Saturday into Sunday hours. Higher end scenarios are indicating
  messy Sierra passes are possible before daybreak, with 8-10
  inches as a first guess along Donner Pass. Spring sun angle will
  work to compete with snow accumulations first thing Sunday
  morning, so accumulations on roadways should be short-lived. All
  told, most of the region will have at least a decent chance for
  wetting rains, with a 50-60% chance for at least 0.5" of liquid
  precipitation across the Tahoe Basin. Recent ensemble
  forecasting for the snow amounts seems to struggle with these
  colder spring systems, but the overall pattern with a deep
  negative-tilted trough, and ample moisture shown in the IVT>250
  kg/ms for the weekend leans us into thinking the amounts may
  increase a bit in future iterations. For now, 1-2 inches at lake
  level in Tahoe is not out of the question, with potential for
  up to 3-4 inches on elevated surfaces. HRICH

&&

.AVIATION...

* VFR conditions through today, although westerly winds will
  increase this afternoon for western Nevada valley terminals to 25-
  30 kts.

* Friday will feature pleasant flying conditions with light winds
  and clear skies though around 03z. There is a slight (10-15%)
  chance for showers for KMMH Friday afternoon.

* SW winds will increase Friday night into Saturday morning,
  signaling the arrival of the next system. Mountain snow showers
  and valley rains are possible through Saturday, with a colder
  airmass allowing snow levels to drop to 5000-5500 feet. This may
  affect Sierra valley runways KTRK and KTVL for Sunday morning
  with snow accumulations possible before the sunrise. HRICH

&&

.REV Watches/Warnings/Advisories...
NV...Winter Weather Advisory from 11 AM Saturday to 8 AM PDT Sunday
     NVZ002.

     High Wind Watch from Saturday morning through Saturday evening
     NVZ001-003.

CA...Winter Weather Advisory from 11 AM Saturday to 8 AM PDT Sunday
     CAZ071>073.

&&

$$

NWS REV Office Area Forecast Discussion