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Area forecast discussion 
National Weather Service Reno Nevada
244 am PDT Friday Aug 22 2014

an area of low pressure will move into the Pacific northwest and
bring increasing winds and critical fire weather conditions today.
Cooler temperatures will reach the area Saturday with dry and warm
conditions next week.


Short term...
water vapor satellite imagery showing an upper level trough axis
crossing into the Pacific northwest. Jet winds along the base of
the trough are beginning to create gusty conditions on the Sierra
with 50 miles per hour gusts currently reported atop Slide Mountain.
Increased winds will become widespread today with peak gusts
reaching 30-40 miles per hour mainly north of Highway 50 with around 30 miles per hour to
the south. Winds will increase by late morning which has prompted
lake wind advisories for Lake Tahoe and Pyramid Lake where hazardous
boating conditions are expected. The combination of low humidity
and gusty winds has also prompted red flag warnings for portions
of the Sierra front including Reno/Carson City/Minden extending
eastward into the western Nevada basin and range. See the fire
weather forecast discussion for more details. Areas of reduced
visibility from blowing dust are possible downwind of Dry Lake
beds and desert regions.

In addition to the gusty winds, isolated showers will be possible
mainly across Pershing County as weak cold front and modest
instability brushes this region. Behind the front winds will shift
northerly overnight with breezy conditions expected. Overall dry
and cooler conditions will be in place by Saturday with high
temperatures mainly in the low 80s across western Nevada and low
70s for Sierra valleys. Cool overnight lows will develop Saturday
night with colder Sierra valleys dipping into the 30s.
Temperatures will rebound back into the middle and upper 80s for
western Nevada and upper 70s for the Sierra on Sunday with clear
skies and light afternoon breezes. Fuentes

Long term...Monday through Thursday...
no significant changes were made to the inherited extended forecast
this cycle. Most medium range models are in good agreement with
lifting the upper trough out of the region early in the forecast...
then building a ridge before flattening the ridge toward the end of
the forecast period.

The Gem is the outlier early today...dropping a weak closed low into
the region late Monday. This lifts out fairly fast and has no
support from the gefs ensemble members. After near average temperatures
Monday...highs will begin to rise as the ridge builds Tuesday and

By Thursday the ridge begins to flatten a bit as a deep trough
organizes over the Pacific northwest and begins to sag south. This should lead
to increased winds by Thursday and this is reflected in the
forecast. The temperatures Thursday are still likely to be above average as
increased winds bring increased mixing. 20

an approaching upper low and dry surface boundary sliding south
southeast through the day will bring increased winds this afternoon.
Gusts along the east side of the Sierra into the basin and range
could reach up to 35 kts at times. Lesser winds gusts are likely near
the Oregon border and south toward Mammoth Lakes and Hawthorne.
Increased winds aloft will likely bring periods of turbulence over
the mountains of western Nevada and the Sierra.

VFR conditions are likely most areas. The only exceptions will be
reduced visibilities in blowing dust across western Nevada where the
stronger west winds blow across dust sources. Downwind of the Alkali
Flats and sinks visibilities could be reduced below 1 mile at times
and dust could be lifted to around 6k feet. Winds decrease later
tonight and remain fairly light Saturday and Sunday. 20

Fire weather...
approaching upper level area of low pressure will drag a mainly dry
surface front through the region by this evening. Stronger middle to
upper level winds will mix fairly dry air to the surface south of a line
from Portola to Lovelock. Strongest winds should fall within a band
from the Sierra front east into the Fallon and Lovelock areas and
south to around Walker and Yerington.

Red flag warnings were issued for zones 450 and 453 yesterday and
these remain in place. There could be a brief period of critical
conditions in southern parts of 278 and northern 273 as well...but
coverage is not likely to be widespread enough to warrant issuance
of warnings for these areas.

Winds could gust close 40 miles per hour this afternoon and evening with relative humidity
values down to near 10 percent in the warning area. Localized gusts
to around 30-35 miles per hour are possible in other areas. Relative humidity will be a bit
higher to the north near the Oregon border as well.

Winds shift to the north tonight most areas then decrease. There
could be gusts to 35 miles per hour briefly from the northwest late tonight
east of a line from Cedarville to Hawthorne. This would delay relative humidity
recoveries those areas. Winds decrease for Saturday and Sunday then
become more typical of late Summer by the middle of next week. 20

Rev watches/warnings/advisories... flag warning from 11 am this morning to 8 PM PDT this
evening nvz450-453.

Lake Wind Advisory from 11 am this morning to 11 PM PDT this
evening nvz004.

Lake Wind Advisory from 11 am this morning to 11 PM PDT this
evening nvz002.

California...Lake Wind Advisory from 11 am this morning to 11 PM PDT this
evening caz072.



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