Tuesday 11 September 2012

What a difference a day makes!  The migration pipeline has relieved a bit of pressure.

The high pressure ridge displaced the low that has influenced our weather for the past few days and we had some decent winds out of the north; the skies cleared and the temperatures dropped a bit.  The result: moderate to heavy migration with radar returns up into the 30 dBZ range last night.

Although the regional composite doesn’t show it, all five of our regional stations had these heavy returns last night — a very big and widespread push south.  I put a static shot from the Seattle area radar, ATX, to show a very heavy stream of migrants crossing the Straight from Vancouver Island to the Port Townsend area.  This flight pattern can be seen many times during the season — pretty impressive.

As i was out this morning around 4:00 AM PDT numerous mixed specie flight calls could be heard.  I was on my way to work so i didn’t take a count but easily 25 – 40 per minute.

Taking a look at the national picture: note the strong southerly winds shutting down migration up the Central and Mississippi Flyways.  That’s ok, that area has been a super highway for most of the season.