Favorable 20 knot winds out of the NW brought the heaviest migration event of the season. A snapshot of the regional mosaic (at the end of this post) shows solid birds from Vancouver Island to Salem where the radar stops. We should assume the same would be seen in the southern valley.
First image is of the winds aloft at 850 mb (approx 5000 ft). Winds are moderate and out of the NW behind the latest cold front. Migration ready birds have taken advantage of these favorable conditions in spades last night!
Second image is of the surface winds and pressure. We’re not seeing any real organized system in our area currently.
Third image is a snapshot of the base velocity showing north to north to south directionality at a peak of 25 to 35 knots. Birds are taking advantage of the tail wind and are booking it down the Western Washington and Oregon valleys.
Fourth image is the animated gif with snapshots every half hour of the base reflectivity above radar station RTX. The radar was in clear air mode last night so density readings spot on. Migration event was thick and heavy last night!
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 6:42 pm pdst.
Below is a snapshot of the regional mosaic at 10 PM PSDT. Looks like Spokane was offline last night. Pendleton was in precipitation mode but some birds are definitely in migration mode over there too. The local situation is astounding. Solid birds from Vancouver Island to Salem with densities reaching 20-25dBZ. Also shown is a static image of the KATX station in Seattle. You can see the birds jumping off Vancouver Island and loading up the Sound.
Good birding, good birding indeed!