http://www.wunderground.com/blog/JeffMasters/comment.html?entrynum=3027

While it’s been an unusually hot, muggy June across much of the Southeast, the
burners will soon be going full blast out West. Models are consistent in
building strong high pressure across the western states late this week into next
week. The results will be scorching temperatures, especially in parts of eastern
Washington and Oregon where warm, dry weather in recent weeks has left the
ground already parched. Highs are projected to range from 100°F to 110°F over
most of the next 4 to 6 days across a large area. Excessive heat watches are in
effect for both Portland and Seattle.

http://www.wrh.noaa.gov/climate/monthdisp.php?stn=KBOI&year=2015&mon=6&wfo=boi&p=temperature