Weather

419 
fxus65 klkn 272100 
afdlkn 


Area forecast discussion 
National Weather Service Elko Nevada 
159 PM PDT Wednesday Aug 27 2008 


Synopsis...dry conditions and the return to above normal 
temperatures are expected this week...with the possibility of 
thunderstorms during the weekend. 
&& 


Short term...tonight through Friday. Models in good agreement 
during short term period. Dry west to northwesterly flow aloft will 
remain across County Warning Area through Friday. A broad ridge over the eastern 
Pacific moves onshore by late Thursday. This will allow temperatures 
to warm up into the 90s most areas by Friday. Winds will be lighter 
Thursday center of the high moves over the area. Otherwise little 
change in previous forecast. Harmer 


Long term...Friday night through next Wednesday...models continue 
to show a major shift in the overall pattern by late in the weekend 
and early next week. European model (ecmwf) and GFS show a strong polar trough 
digging southeast out of the Gulf of Alaska on Saturday...which is forecast 
to push into the western United States by Sunday. Warm temperatures are 
expected to continue on Saturday...ahead of this system...as upper 
level high pressure drifts east of the Great Basin and into the southern 
Rocky Mountain states. With midlevel winds backing out of the south 
as the high drifts east of the area along with the Pacific trough 
digging south across the Pacific northwest...expect some midlevel moisture 
to push north across portions of central and NE Nevada Saturday. May see 
some high based thunderstorms across the area Saturday afternoon so kept 
weather in the forecast for now...although current model runs show an 
Alto-stratus cloud deck that may limit low level instability. Models 
then show strong upper level trough digging south into the Great 
Basin region by Sunday morning with 700mb temperatures lowering to -5c 
along the Oregon and Idaho border. European model (ecmwf) is 6 to 12 hours earlier 
than the GFS and UKMET...showing the cold front pushing across northern 
Nevada as early as Sunday afternoon...while the GFS shows the front 
pushing into eastern Nevada around midnight Sunday night. European model (ecmwf) also has 
trough axis and colder air slightly further south in comparison to 
other models. Models do agree that this system will be 
progressive...so do not expect it to last through the middle of next 
week. Continued to lower maximum and min temperatures through early next week 
since models continue to trend cooler with each run. Increased pop 
across eastern Nevada...which will be the favorable area to see rain showers 
and some thunderstorms with favorable dynamics as a strong 100 knots jet maximum 
moves into central Nevada. If current models verify...may still be 10 degrees 
too warm on high temperatures Monday and Tuesday with GFS showing highs 
struggling to reach 60-65f across the northern Nevada valleys...and high 60s 
to lower 70s across central Nevada. Lowered min temperatures into the upper 30s 
across northern and eastern Nevada Tuesday morning...which are still several degrees 
warmer than MOS. Can not rule out the possibility of the first hard 
freeze across northern Nevada Tuesday morning with dry air over the area 
resulting in good radiational cooling. 


Models then show westerly flow over the Great Basin by Wednesday 
with slowly warming temperatures...but dry conditions. Tt 
&& 


Aviation...VFR conditions and light winds are expected through 
tonight as high pressure builds over the region. 
&& 


Fire weather...a broad upper level ridge will be moving onshore 
over the next couple of days...keeping dry conditions over the 
fire district for the remainder of the week. Expect little change in 
temperatures on Thursday from today and lighter winds. Expect 
humidity recoveries to be around 35-50% tonight. Moisture will 
increase along with thunderstorms during the weekend with a possible 
significant cool down for early next week. 
&& 


Lkn watches/warnings/advisories...none. 


$$