982
FXUS65 KREV 162039
AFDREV

Area Forecast Discussion
National Weather Service Reno NV
139 PM PDT Thu May 16 2024

.SYNOPSIS...

Unseasonably warm temperatures will persist through Saturday with
afternoon breezes. Other than low chances of showers and
thunderstorms in the eastern Sierra and far western NV south of
Highway 50 on Saturday, conditions will stay dry. Low pressure
will keep the breezes around for next week with temperatures
remaining seasonally mild.

&&

.DISCUSSION...

* Unseasonably warm temperatures through Saturday with highs
  remaining about 10 degrees above normal.

* Afternoon breezes (typical of early summer) continue into the
  weekend. Nothing crazy, but locally choppy lake waters and
  impacts to activities more sensitive to wind.

* 10% chance of thunder along the Mono County crest late this
  afternoon and a 15-30% chance of showers and thunderstorms south
  of Hwy 50 Saturday afternoon. Otherwise, dry conditions will
  prevail through the weekend.

THROUGH SATURDAY:

Warmest temperatures will be this afternoon with temperatures
atop Slide Mt in the mid 50s as of 1 pm, 6 degrees warmer from 24
hours ago. So it will be close whether we can hit 90 degrees at
the airport. Winds were also beginning to pick up on the ridges
and should mix down into the lower terrain by late this afternoon.
These breezy conditions will persist across midslopes and ridges
overnight as a weak front moves into the northern Great Basin and
turns our flow more N-NE for Friday and cools us down a few
degrees Friday afternoon. An isolated storm or two cannot be ruled
out along the Sierra crest south of Markleeville Friday afternoon
as a few ensemble members show some light QPF. Given the light
flow and very warm temperatures, we maintained a 10% chance.

For Saturday, westerly breezes will pick up again ahead of a
trough moving through the PacNW. lake waters. Strongest winds
will be north of Hwy 50 where gusts to 30-35 mph may be
sufficient for some localized choppy lake waters. Farther south
across Mono-Mineral-S Lyon counties, ECS/GEFS continue to
indicate the potential for isold-scattered showers/storms (15-30%
chance). Instability is marginal, but a few stronger cells could
produce some small hail, wind gusts to 40 mph, lightning and
brief heavy rain. Temperatures will be similar to Friday, still
about 10 degrees above normal.

SUNDAY AND BEYOND:

Ensemble clusters show a trough with afternoon breezes and
temperatures cooling back to near or slightly above normal levels.
There is still a lot of spread in the temperature field which
indicates lower confidence in the details regarding depth and
track of upper level features. Blended guidance has trended drier
overall with lower chances for showers. This overall trend of
troughiness and seasonal temperatures may persist through the rest
of May.

Hohmann

&&

.AVIATION...

* 30-HR Operating Period (through 18/06Z): VFR. W-NW winds 10-15
  kts shifting to the N-NE after 15Z Friday as a front works
  through the Great Basin. Gusts 20-25 kts through 03Z this
  evening. There is a 10-15% chance of showers/thunder near the
  Sierra crest after 21Z Friday vicinity KBAN-KMMH.

* This Weekend: A trough will drop southward into the Great Basin
  with breezy daytime W-NW winds, gusts 20-30 kts at times. There
  remains a 15-30% chance of showers/thunderstorms eastern Sierra
  Saturday afternoon, potentially impacting KMMH-KBAN-KHTH. A few
  model scenarios indicate a 10% chance of a storm drifting as
  far north as KTVL/KMEV.

Hohmann

&&

.HYDROLOGY...

Unseasonably warm daytime temperatures and mild nights, combined
with higher solar angles, longer days, and limited cloud cover,
will continue to increase snowmelt rates late week. Even the
higher elevation deeper snow areas have begun to melt in earnest.

This rapid melt will lead to elevated flows with rivers and
streams running cold and fast, most notably in areas draining
significant terrain over ~7500 feet from Lake Tahoe south through
Mono County. Rivers and streams in this area will remain high
through the weekend, with the highest flows likely Thursday into
Saturday. Cooler temperatures and a depleting snow-covered
contributing area will help reduce flows somewhat Sunday into
early next week.

While these high and cold flows can be hazardous to recreationalists,
flooding is very unlikely. Remember the highest flows are
significantly lagged from the heat of the day and can often occur
at night.

More steady high flows will also continue along the Lower
Humboldt, with additional rises likely in very late May or early
June.

Please use extra caution around local rivers and streams which
will be running fast and cold and can be very hazardous.

TB

&&

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

$$