Significant Heat in the Northwest U.S.; Tropical Rainfall Potential in the Southwest U.S.

A significant late season heat wave continues in the interior Pacific Northwest for at least one more day before easing somewhat Friday into Saturday. A combination of monsoonal moisture and tropical moisture ahead of tropical cyclone Lorena will bring a marginal to slight risk of excessive rainfall across the southwest U.S. through Saturday which may bring areas of flooding. Read More >

A very noticeable pattern change took place throughout May compared to April and March as very warm and dry weather prevailed. This led to a reversal from pretty widespread areal flooding due to the rapid melting of an area-wide deep snowpack in April to a very dry pattern with flash drought conditions developing through the month. Rainfall was below average everywhere, and for some places, several inches below average. Ashland recorded the driest May on record! Temperatures were also several degrees above average everywhere. As a result, rivers and streams are starting to fall below normal levels.