PNW Migration Update – 24 April 2013

Mild headwinds not withstanding, birds were headed north. Heavy migration was the scenario for the Willamette Basin last night, mainly in the east county.  Coastal movement was not as pronounced as yesterday.  There should be some pretty good turnover today.

The high pressure system that has been dictating our weather is showing some signs of weakening as a competing low is building in the Bearing Sea.  It probably wont displace the high but it may entrain some colder air and bring in some clouds and instabilities over the next few days.  We’ll see.

Nationally – the Atlantic Flyway, and especially in the SE, was quite active from Florida to Maine.  The Mississippi and Central Flyways were shut down again.  But of major interest to us over on the West Coast — the Pacific Flyway was on the move.  On the National Composite check out the Las Vegas radar!  That is the densest returns from that station that i can recall.  The central valley of California was lit up again last night.  Those birds are headed this way — look busy, they’re coming.  Compare the Winds Aloft plot and the National Reflectivity Composite to get perspective on how migrating birds interact with weather conditions.

The problems in programming have been fixed (for now) and we once again have Reflectivity and Velocity loops for today’s gallery.