First image is of the winds aloft at 850 mb (approx 5000 ft). Winds over the state were light and variable.
Second image is a snapshot of the base velocity showing mainly north to south but mixed directionality at a peak of 5 to 10 knots. This could very well be of a mix of biological targets and dust or smoke from the fires on the east side.
Third image is an animated gif with snapshots every half hour of the base reflectivity above radar station RTX. Animation runs from around 8:00 pm pdst yesterday evening through 5:00 am pdst this morning. (Click on the thumbnails to view the full-sized images and animation.)
Sunset last night was at 7:45 pm pdst.
Density was very low last night, but apparent.
As an aside, Variegated Meadowhawk (Sympetrum corruptum) “migration” was reported from Astoria to Newport yesterday.