Mammoth Lakes, California 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

229
FXUS65 KREV 251017
AFDREV

Area Forecast Discussion
National Weather Service Reno NV
317 AM PDT Tue Aug 25 2026


.KEY MESSAGES...

* Isolated showers and thunderstorms are possible today, mainly in
  Churchill, Mineral, and Mono Counties.

* While smoke from the Hawk Fire may continue in the Reno/Sparks
  metro area today, impacts may decrease with breezy winds and
  better ventilation.

* Increased winds will bring elevated to critical fire weather
  conditions and potential recreational impacts on Wednesday through
  Saturday.

&&

.DISCUSSION...

For today, the latest RAP analysis of the upper air pattern shows
the CWA with a southwesterly flow aloft and still being
underneath the western portion of a high pressure ridge over the
Southwestern CONUS today. Another feature to mention is a PacNW
low which is projected to move closer to the WA/BC coast through
the day. With this low in place, models are showing slightly
breezier SW winds today within the region with gusts up to around
25-30 mph. These winds will continue elevated fire weather
conditions in NE CA and NW NV today. Forecast guidance is also
showing around a 15-25% chance for isolated showers and
thunderstorms within Churchill, Mineral, and S. Mono Counties
between 2-8 PM. Forecast soundings show an inverted-V shape with
MUCAPE values between 100-200 J/kg and DCAPE values over 1000
J/kg, so thunderstorms will be capable of producing gusts up to
around 45-50 mph today. Forecast PW values are between 0.6-0.8
inches, so brief periods of heavy rainfall could be possible
though flooding is not anticipated to be a threat as storms that
occur will be moving quickly and short lived. The remainder of the
region shows signs of staying on the dry side.

While the Hawk Fire may continue to generate smoke within the
region especially near the Reno-Sparks area, the latest HRRR run
of the near-surface smoke product does not show increasing smoke
concentrations today. This may be due to better ventilation with
breezier winds, but cannot rule out some morning haze when lighter
winds prevail. It is interesting to note that the HRRR is showing
potential smoke in NE CA from the Timber Fire burning on the CA
coast early today. Please continue to monitor AirNow.gov for the
latest air quality conditions and forecast information in your
area.

Going forward through the rest of the week, forecast guidance is
showing the aforementioned PacNW low moving closer to the BC coast
on Wednesday, making over BC on Thursday, and continuing to trek
into SW Canada going into the weekend. This causes the upper jet
over the CWA to strengthen even more which will translate to gusty
winds when they mix down to our surface here. The forecast is
showing wind gusts up to 35 mph (up to 40 mph in wind prone areas)
on these days, which will lead to critical fire weather concerns
(see Fire Weather Section for more details) as well as potential
recreational and travel impacts within the region during the
latter half of the week. Cannot rule out some potential diurnal
showers on Wednesday in W NV as well, but chances look to be low
(<15%) at this time. The GFS shows the best chance for
precipitation for the rest of this week being on Friday when a
potential weak cold front passes through the region. Daytime high
temperatures drop slightly to the middle to upper 80s in the NE
CA and W NV valleys with Sierra Communities being in the 70s going
through the weekend. Will continue to watch to see if more models
agree with the GFS going forward. Beyond this, extended guidance
does point to dry conditions early next week at this time. -078

&&

.AVIATION...

VFR conditions are expected at all area TAF sites today and tonight
Surface winds in the region gusting up to between 20-25 kts are
forecast between 25/17Z-26/03Z. The latest HRRR smoke product does
not show much impact from Hawk Fire smoke today compared to the
previous days, but cannot rule out slightly reduced visibilities
near the fire in Washoe County. Not anticipating flight rules to be
reduced at this time due to smoke at KRNO, but will continue to
monitor in case this changes.

As for precipitation chances today, there is a 15-25% chance for
isolated showers and thunderstorms in Churchill, Mineral, and S.
Mono Counties between 25/21Z-26/04Z. Lesser precipitation chances
are seen in the NV Basin and Range on Wednesday afternoon. -078

&&

.FIRE WEATHER...

Breezy SW winds with gusts up to around 25-30 mph and RH reductions
of 15-25% will support elevated to isolated critical fire weather
conditions this afternoon across the Sierra Front and NE CA,
including the Hawk Fire. Tuesday night RH recoveries in these areas
are forecast to be between 35-50%.

The latest SPC Fire Weather Outlook shows a 40% chance for critical
fire weather due to wind and low RH in NE CA and NW NV through the
rest of the week with the Friday showing a slight decrease in NW
NV coverage. The forecast shows increased winds with gusts
upwards of 35 mph (40 mph in wind prone areas) mainly for the
Sierra Front and NE CA Wednesday through Saturday. Currently, days
with the most widespread critical fire weather conditions in these
areas looks to be Wednesday, Thursday, and Saturday. Please continue
to watch for further updates in case fire products need to be
issued. -078/Justin

&&

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

$$