A Dry End of Summer

Summers are typically dry in the Northwest, but by now the probability of precipitation typically rises significantly.

But this year we can look forward to a very dry end of summer--with no moisture for the next week or more.   

The precipitation anomaly (difference from normal) for the West Coast  over the past month shows an interesting story (see below).  Most of Washington has been slightly drier than normal, particularly the western slopes of the Cascades.    The southwest U.S. has been particularly dry, since the southwest "Monsoon", which typically brings thunderstorms in July and August to Arizona and New Mexico, has been much weaker than normal (a.k.a., the NONSOON).   And parts of California have been wetter than normal due to tropical moisture pushing northward (and causing all the lightning that ignited California).

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