443 
fxus65 krev 052156 
afdrev 


Area forecast discussion 
National Weather Service Reno Nevada 
255 PM PDT Sat Jul 5 2008 


Short term... 
a shortwave now appoaching the Oregon coast will move through the 
northwestern Continental U.S. On Sunday. The zonal flow it is imbedded in should pull 
the feature to the east. The main effect for the krev County warning forecast area will be 
an increase in cloudiness tonight and Sunday in the northern zones. 
Under mostly sunny skies temperatures on Sunday should rise into the 
upper 90s in western Nevada and to near 90 in the Sierra. 


On Monday the broad trough that stretches from the southeastern Continental U.S. To the 
eastern Pacific will build into the Great Basin. Warm air advection 
will help temperatures in the western Nevada valleys rise to around 100 
degrees Monday afternoon. Monsoonal moisture should remain south of our 
area and not make it much farther north than the Colorado basin. As 
a result skies will remain mostly clear in a dry air mass. 


On Tuesday the ridge is prognosticated to strengthen even more. The GFS 
forecasts 500 mb heights rising to 591 dam or higher by 00z Wednesday. 
Temperatures should easily reach 100 degrees or greater across most 
of western Nevada Wednesday afternoon. Highs across much of the Sierra will 
be in the 90s. A public information statement has been issued 
listing record high temperatures for many locations across the County warning forecast area 
through mid-week. O'Hara 


Long term...Wednesday through Saturday... 
latest medium range guidance remains in good agreement through early 
Thursday...with the upper level ridge over the southwestern Continental U.S. 
Beginning to flatten as a trough moves into the Pacific northwest toward the 
end of the week. 12z GFS is trying to hold onto the ridge one extra 
day...through Thursday night before allowing troughing to move into 
northern California. 12z Euro is bringing the troughing into California/Nevada 
nearly 12 hours earlier...which would result in a cooler day 
Thursday. This is the same trend that the 00z Euro was doing 
earlier. But...latest GFS ensemble mean matches up well with the 
12z deterministic GFS...with 500mb heights over 590 dm over central 
Nevada Wed/Thu. Bottom line... trended forecast temperatures toward GFS 
MOS...with temperatures peaking out Wednesday/Thursday in the western Nevada valleys in 
the low 100s and around 90 in the eastern Sierra valleys. Some 
records may be in danger of being broken on Wednesday...but records on 
Thursday/Friday will be difficult to break due to the heat wave of 
2002..where we saw temperatures soar to 108 in Reno for both the 10th and 
11th of July. Temperatures are expected to drop after Thursday...as the 
ridge retrogrades to the eastern Pacific going into next weekend. Hoon 


&& 


Aviation... 
VFR conditions will continue through tonight. No additional new 
fires have started close to the forecast area and winds continue 
pushing most of the smoke north of the taf sites. With winds 
gradually becoming more west-northwest today and gusts increasing to 15 to 25 
kts this afternoon some smoke should drift back into the ktrk...ktvl 
and krno areas...but visibilities should fall to no worse than 6 miles. Not 
anticipating any smoke in the vicinity of klol. Mlf/hoon 


&& 


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


$$ 


Http://weather.Gov/Reno