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Area forecast discussion...corrected 
National Weather Service Reno Nevada 
252 PM PDT Friday Jul 4 2008 


Short term... 


Short wave over northern California will move east across Nevada this evening and 
overnight. An increased thermal gradient ahead of this shortwave is 
producing gusty winds across the area. Gusts are generally 25-30 miles per hour 
with local gusts up to 35 miles per hour in wind prone areas. Winds over Lake 
Tahoe are gusting 20-25 miles per hour with only local gusts above 25 miles per hour. 
These winds are less than lake Wind Advisory...and based on web 
cameras around Lake Tahoe general 1-2 foot waves are occurring and 
2-3 foot wave on the North Shore. Therefore will refrain from 
issuing a lake Wind Advisory. However the lake will be choppy 
through this evening before the winds subside. Winds will decrease 
in the Tahoe basin around 7-8 PM...but will likely not decrease in 
western Nevada...including the Reno/Sparks area until 10-11 PM tonight. 


Smoke will continue to be an issue tonight and Saturday as southwest 
flow transitions to west than northwest flow on Saturday and Sunday. 
Smoke will likely spread further south into southern zones on Saturday. 
Area web cameras showed even smokey conditions this morning near 
Mono Lake and Lee Vining. Therefore smoke and haze was added to the 
forecast further south. Winds become lighter Sunday and more so on 
Monday as a strong ridge of high pressure builds into the area. This 
may help with the smoke east of the Sierra crest as westerly winds 
will be much weaker and will not transport as much smoke to the 
east...however haze may still get trapped in the valleys. 


Models are indicating another short wave moving across the area over 
the weekend...but models differ on timing. The GFS has the wave 
coming across Saturday night into Sunday while the NAM/Euro hold 
this wave off until Sunday afternoon. The GFS produces an area of 
instability in the left exit region of a 90kt jet over northern zones 
ahead of this wave on Saturday. However this is not supported in the 
other models yet...so forecast will remain dry at this time 


Hot temperatures will be the main story next week as high pressure 
strengthens. High temperatures will climb into the upper 90s to low 
100s over western Nevada on Monday and into the upper 80s to low 90s in the 
Sierra. See climate discussion below for more information. Gmcguire 




Long term...Tuesday through Friday... 


Main issue during the extended period will be the probable record 
high temperatures through midweek. This is covered more extensively 
in the climate section below. 


On Tuesday the strong ridge over the western Continental U.S. Will continue to 
control the weather pattern. The GFS...European model (ecmwf) and Canadian all show 
the ridge extending across the southern tier. From Georgia west to Southern 
California 500 mb heights are prognosticated to be above 588 dam at 00z 
Wednesday. Not much change in the pattern for Wednesday with 
impressive 500 mb heights reflecting the extremely warm air mass 
over the southwestern Continental U.S.. skies should be mostly clear over the krev 
County warning forecast area Tuesday and Wednesday. Cumulus buildups are possible during 
the afternoons...mainly south of I-80 in the area of the greatest 
low level instability. 


The models bring an upper low southeast out of the Gulf of Alaska 
toward the Pacific northwest on Thursday. The models keep the upper low to 
our north in the zonal flow across the northern tier Thursday and Friday. 
This seems reasonable with such a strong ridge over the southwestern Continental U.S.. 
will keep the forecast dry through the extended due to the strong ridge 
over the region. Have increased cloud cover somewhat over Mono and 
Mineral counties mainly on Thursday and Friday due to the strong 
low level instability and the possibility of moisture advecting into the 
region ahead of the system to our north. O'Hara 
&& 


Aviation... 


VFR conditions will continue through Saturday. Wind gusts of 25 to 
30 kts are possible at the terminals between 21z and 03z. Smoke 
should filter back into the area this evening as the winds die down. 
However visibilities should remain VFR. O'Hara 
&& 


Climate... 


Hot conditions are expected during the extended period. Record high 
temperatures are probable at many locations across western Nevada and 
even into the Sierra. Record warm minimum nighttime temperatures 
are also possible...especially at Reno. 


Record high temperatures Monday through Wednesday are in the upper 90s 
to lower 100s at locations in western Nevada. Record highs at Sierra 
locations are generally in the 90s. High temperatures for July 10th 
and 11th (thurs and fri) are from the historic heat wave in 2002. 
These records for Thursday and Friday do not seem to be in jeopardy 
at this time. A public information statement has been issued listing the 
record highs that may be broken next week. O'Hara 
&& 




Rev watches/warnings/advisories... 
Nevada...none. 
California...none. 
&& 


$$ 


Http://weather.Gov/Reno