The National Weather Service in Pendleton has issued a Red Flag warning for nine counties in eastern Washington from 5:00pm on Friday afternoon until 5:00pm on Sunday afternoon.
A low pressure system is expected to move into the area tonight and unstable conditions will continue through Sunday afternoon. Thunderstorms are possible over the next 48 hours, and will likely include frequent lightning. Because of the extremely dry conditions in the area, that lightning may cause several new fire starts.
The National Weather Service says storms will develop over eastern Oregon this evening and then move into central Washington by Saturday morning. Thunderstorm activity will persist across northeast Oregon and eastern Washington through Saturday night. Coverage will diminish on Sunday but some storms may linger from the Blue Mountains eastward. Gusty winds and hail will be possible. Frequent lightning is expected.