PNW Migration Update – 16 April 2013

In spite of the northerly winds, with westerly components closer to the coast, birds were in the air last night.  The winds were not particularly stiff and without the rain avian advantages were taken.  The flight wasn’t all that spectacular but we did reach 25 dBz in spots over the night, all in the east county area.  Also it looks like most of the flights were out of the area and only a trickle coming in – best seen on the velocity loop.  Unfortunately you’ll have to go to the Real Time Weather web site and run your own loops as my server is puking up errors this morning.  The images in today’s gallery are static.

The weather pattern continues to be dominated by a high pressure ridge that is just sitting out in the Pacific.  It is pulling pockets of cold air down out of the Alaskan Gulf now and again bringing us intermittent instability.  I’m not seeing anything that would suggest much of a change in the near future.  Expect continued turnover at slow to moderate levels depending on wind speed and rain cells.

Nationally we see a band of weather stretching from New York and westward down the Ohio Valley.  This puts up a barrier and creates some localized fallout conditions.  Note the pocket of trans-gulf migrants off the Keys and the heavy movement in the Southeast.  Behind the weather we see pockets of flight, most prominent in Wisconsin – migrants already in the area continuing north.  For specifics in other areas check out the NEXRAD Migration Trackers found in the sidebar links.