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Area forecast discussion 
National Weather Service Elko Nevada 
347 am PDT Thursday Aug 21 2008 


Synopsis...a storm system moving across the Pacific northwest will 
bring slightly cooler temperatures and breezy conditions to the 
Silver state today and Friday. Thunderstorms are expected to develop 
Friday...Saturday...and Sunday as moisture sneaks in under building 
high pressure. && 


Short term...tonight through Friday...infrared satellite imagery shows 
only a few clouds skirting the northern borders with Idaho and or. 
Evidence of jet streaks pushing into the Pacific northwest also 
noted. Otherwise substantial clearing over most of the forecast area 
this morning. Water vapor imagery shows dry slot being infused into 
the flow south of the main jet energy off or and Washington at this time. 


Short term models are in excellent agreement through Friday. Upper 
level low will be forcing its way into the Pacific northwest today. 
This will be the first of a deepening set of troughs to move in from 
the Pacific Ocean over the next week...resembling an early fall 
pattern. A slow cooling should result. 90 degree readings today and 
Friday will be scant. As this system approaches...winds will continue 
basically in the breezy category across the north. 500 mb heights per GFS 
are showing up as low as 582dm today over northern Humboldt and Elko 
counties today...with a rebound 2-4 dm on Friday. Upper low axis will 
pass along northern zones today when a dry cold front begins to drag 
through. Sprinkles are possible across the north...both Humboldt and 
Elko counties as the upper jet brushes the state. However system is 
pretty dry this far south. 


Highs today will be generally 80 to 85 and 85 to 90 on Friday with a 
shortwave ridge building ahead of next trough that proposes to 
deepen further. An isolated dry thunderstorm or two will be possible 
Friday afternoon over the higher terrain of central Nevada. Will 
add some minimal probability of precipitation along Highway 50. Lw 


Long term...Friday through Wednesday...sandwiched between The 
Four Corners high and a low pressure center approaching from the 
northwest...the Great Basin will be under a moist and unstable 
southwesterly flow Saturday afternoon...with the threat of showers 
and thunderstorms across the Central Highlands and northeastern 
Nevada. Area of instability is more confined on Sunday...mainly just 
over the eastern half of Elko County. Easterly progress of the upper 
low slows late Sunday into early next week as the low makes its way 
into Oregon and Washington. Its at this time that model solutions 
begin to diverge. GFS takes the low further south than does the 
European model (ecmwf). If GFS is correct...could see a 10-15 degree cool-down from 
Tuesday to Wednesday...with a dusting of snow possible above 8000 
feet to northeastern Nevada. For now kept with the cooling trend for 
the middle of next week...but not to the extent that the GFS is 
suggesting. Rood && 


Aviation...VFR conditions are expected across central and northern 
Nevada again today. Gusty winds across northern Nevada will be the 
main concern today...as a disturbance moves through the Pacific 
northwest. Rood 
&& 


Fire weather...a storm system moving north of the state today will 
bring slightly cooler temperatures and breezy conditions to the fire 
district...mainly north in 451 and 452. Humidities will be higher... 
however...so red flag conditions not expected at this time. Winds 
will not be much of an issue Friday as high pressure builds in. A 
warming trend will begin Saturday in advance of next low pressure 
system. An isolated dry thunderstorm or two will be possible Friday 
afternoon in the higher terrain of 455 and 457. A broader area of 
isolated dry thunderstorms will be possible Saturday afternoon in the 
higher elevations of 452...454...455...and 457. Lw && 


Lkn watches/warnings/advisories...none. 


$$