Thursday 17 May 2012 – PNW Migration Update

The stationary high pressure ridge continues off the coast.  That is keeping the winds out of the northwest.  They remain below 10 knots at the surface and aloft.  These light winds are not enough of a deterrent to back up migration.

Locally migration was moderate to heavy last night.  Movement was heaviest on the east side of the valley with sustained heavy returns.  There was a pocket of heavy migration just west of Hillsboro as well.

In the field the listserve chatter is dying down.  There are some uncommon birds around and they get most of the play.  eBird shows Chats, Swainson’s Thrush, Pewees and Willow Flycatchers have arrived in Multnomah and Washington Counties.

The outlook for migration over the next few days remains good.  The wind is forecasted to remain light, under 10 knots, and shift a bit, to more westerly.  The temperatures should get back into the 70’s by the weekend .  It looks like we will have partly cloudy conditions building to possible rain by early next week.  All in all, a very pleasant weekend on tap.

Regionally we continue to have heavy migration in the Rogue Valley.  Conditions are similar to the Willamette Valley – just 10 degrees warmer.

The southern portion of the Pacific Flyway continues to favor migration and we see heavy returns from San Diego to Redding.

Nationally the weather is favoring the Central Flyway. We find the birds are still pouring in from Mexico.  The radars are lit up with heavy returns from Brownsville to Minot.  The Mississippi and Atlantic Flyways are seeing locally spotty migration as weather and winds battle for air space.  The southeast appears to be getting the worst of it.  But the birds will not be deterred and we can see moderate to heavy returns as local conditions allow.

As always — For more detailed migration updates in other regions check:

Wisconsin and New Jersey – woodcreeper  by David LaPuma
Michigan’s Upper Peninsula – The Northwoods BIRDAR by Max Henschell <- NEW!
New England – Tom Auer’s blog
Florida/SE – Badbirdz Reloaded by Angel and Mariel Abreu
PA/Ohio Valley – Nemesis Bird by Drew Weber
NW Ohio – Birding the Crane Creek by Kenn Kaufman
Arizona – Words About Birds by Tim Schreckengost <- NEW!
New Mexico – Albuquerque Birding by Matt O’Donnell <- NEW!
Pac NW – Birds Over Portland by Greg Haworth
Continental US – eBird BirdCast Forecast & Report by Team eBird

Also under NEXRAD Trackers in the sidebar to the right.