544
FXUS65 KLKN 040828
AFDLKN

Area Forecast Discussion
National Weather Service Elko NV
128 AM PDT Thu Sep 4 2025

.KEY MESSAGES...

Updated at 125 AM PDT Thu Sep 4 2025

* Monsoonal moisture continues to build in from the south through
  the week.

* Mix of wet and dry thunderstorms today, with areal coverage
  expanding across the region.

* Friday will see thunderstorm chances peak, and the number of
  wet thunderstorms far outnumber dry.

* Dry conditions return for the weekend as upper flow sifts to
  the WSW bringing in drier air.


&&


.DISCUSSION...
(Today through next Thursday)

Southerly upper level flow drawing moisture farther north Today as
thunderstorms chances continue for Nevada. This upper pattern is
book ended with a broad upper level ridge located over the four
corners region, and a upper level trough that is offshore trying
to push in over the west coast. Thursday and Friday chances peak
at 30% to 70% area wide. There is also a marginal risk of
excessive rainfall Thursday and Friday as PW values rise north of
one inch, and combined with slow storm motion will create a risk
of flooding. Saturday storm chances shift east with the best
chances of storms across Elko and White Pine counties, as the
upper trough lift into Canada as the upper ridge shifts into
southern California. This will change the orientation of the upper
flow to be out of the West-Southwest. This change will push
monsoonal moisture out of Nevada leading to a break in the action
Sunday into Monday. After Monday, models have come into agreement
with the upper pattern for next week. Both the GFS and the EC show
a large upper level trough or closed low developing over the
northern half of the west coast. This trough/closed low will then
stall over Oregon as the upper pattern becomes blocked. Models
show this trough/low holding firm through at least Friday of next
week. This will be a favorable set up for precipitation for Nevada
as this system will bring shower and thunderstorm chances for next
week as well as cooler temperatures, as shortwaves eject into the
SW flow over Nevada. As for temperatures, a cooling trend
continues as moisture and clouds increase. Highs will start in the
upper 70s to upper 80s Thursday, cooling into the mid 70s to mid
80s by Sunday afternoon. For Monday through Thursday Highs will
cool further into the mid 60s to mid 70s. Overnight lows will not
be as cool with clouds on the increase as low range in the low 50
to mid 60s through Sunday morning. Lows do cool through Thursday
of next week as lows return to the low 40s to low 50s.

FORECAST CONFIDENCE & DEVIATIONS:

There is high confidence in the development of afternoon
scattered to numerous showers and thunderstorms across central and
northern Nevada Thursday and Friday.

There is high confidence in wet thunderstorms outnumbering dry,
with the marginal risk of excessive rainfall leading to flooding
for Thursday and Friday.

There is moderate confidence in the upper pattern for Tuesday
through Thursday of next week as models agree on the development
of a large upper level trough over the northern half of the US
West coast that will bring shower chances to Nevada.


&&


.AVIATION...

A few light rain showers expected to persist thru much of the
morning, primarily in vicinity of KWMC with lower probabilities at
KBAM and KELY. Not enough confidence to include VCSH in the TAF
for KBAM or KELY at this time, but will evaluate at the 12Z TAF
package if not before. Otherwise VCTS will be present at all
terminals this afternoon aside for KWMC where VCSH is forecast.
The typical thunderstorm hazards of strong and erratic wind gusts
of 45KT or more, brief reductions in VIS due to rainfall, and/or
brief reductions in ceilings leading to MVFR or IFR conditions.
Thunderstorms and showers dissipate between 03Z and 05Z at all
terminals. Cloud bases anticipated to remain higher than 5000ft
AGL otherwise. Prevailing winds will be generally light thru the
next 24 hours around 10KT or less.


&&


.FIRE WEATHER...

Afternoon thunderstorm activity continues across the region on
Thursday. Initial activity will develop over fire weather zones
425 and 426 by midday before spreading northward to areal coverage
over all fire weather zones by mid afternoon Thursday. Continued
moisture transport from the south will aid thunderstorm
development in being a mix of wet and dry activity early becoming
more wet than dry by late afternoon Thursday.

Friday will see initiation of thunderstorm development over all
fire weather zones by early afternoon. A mix of wet and dry storm
activity over fire zones 424, 437, 438, 469, and 470 is expected.
Further south over 425, 426, and 427 moisture and instability
values are more in line with stronger, wetter storm activity.
Unlike Thursday when storm activity will subside after sunset,
Fridays setup looks more like a prolonged event with storms
lasting late into Friday evening.


&&


.LKN Watches/Warnings/Advisories...
None.
&&

$$

DISCUSSION...98
AVIATION...92
FIRE WEATHER...99