04 Apr 2012 – PNW Migration Update

Local migration was evident once the precipitation eased and moved off to the east.  The radar was in precipitation mode all night so reading the radar for bird targets is more difficult.  Unfortunately i don’t have a velocity loop but i put up a static plot. You can see the clouds moving east and to the west of them are the birds with the north to south directionality.

Once again Oregon birds are stacked up in west counties from McMinnville to Hillsboro.  If it’s not raining under the east clouds  some birds might be over there too — but with their signals obscured by clouds.  The local winds were out of the south aiding any movement.

To our south in California only the southern portion of the state saw appreciable movement; from San Diego to L.A.  The rest of the state looks to be shut down under some precipitation and northerly winds.

Nationally the low pressure cells, that in part, spawned the tornadoes in Texas put northern boundary limits on flight.  Behind the storms birds were moving up into Texas.  Some flights up the Ohio Valley between the cells can be seen.  And a pretty good showing in the Mid-Atlantic from Virginia to New York.

I also put in a couple of static shots of the Florida Keys station KBYX — just because i fancy watching the birds cross the straits from Cuba.

Site News:

The list of NEXRAD trackers continues to grow — check out the links under NEXRAD Trackers.  Two, new to me trackers, are Tom Auer (noted in the post below) covering New England and Drew Weber of Nemesis Bird covering Pennsylvania.

A couple of new sources for Radar Loops.  An incredible archive of daily loops curated by Paul Hurtado brings us today’s National Composite. Everyday he posts a Java Applet that loops 24 hrs of radar images. Here’s last night’s.

And the University of Wisconsin – Madison’s Dept of Atmospheric and Oceanic Sciences which has current three hour NEXRAD loops.