24 April 2015 — PNW Migration Update

Shorebirds continue to move through the area.  Found in those isolated spots with suitable habitat. I don’t think anything new, that hasn’t been mentioned earlier, has shown up in the area.  But i’ve been quite busy with other tasks and i may have missed something.

Take a look at the winds aloft plot and you can see a concentrated low has formed bringing cold air out of the Gulf of Alaska and turning the winds to a more favorable direction for northbound migrants.

Unfortunately there are associated rains and that always dampens determination.  But give a bird any break in the weather and they will take advantage of that.  I put in the HC plot today so it is easier to pick out the birds from the weather.  It looks like they had a few hours of flight before giving up for the night.

If you look again at the winds aloft plot one might surmise a continental scenario:  looking good for the Central Flyway, and not so good for the Atlantic.  So i put in a snapshot of the National Radar Composite to see if that is how it played out last night.

Winds Aloft Plot: Source

National Radar Composite: Source

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15 Apr 2015 — PNW Migration Update

We have an advancing ridge of high pressure and a retreating trough of low — always a dicey proposition for spring migrants headed north.  There was a bit of movement last night, but it was on the moderate side at best.

Best chatter on the Pacific Flyway listserves comes from the Central Valley where Lazuli Bunting was noted.  Also Yellow-headed Blackbird and Western Flycatcher have made it to the Portland area.

There was some excellent trans-Mexican Gulf migration conditions last night and the flight into Key West was spectacular.  But for some reason i can’t download the file.  Maybe Badbirdz will archive a loop today.

13 Apr 2015 — PNW Migration Update

Excellent conditions – clear skies and a bit of a tail wind – lots of birds moving up the Pacific Flyway.

Bank Swallows and Yellow-breasted Chats have made it into the San Diego Area.  Tanagers are up into the Central Valley.  And Hermit Warblers are moving through the Coast Range here in Oregon.

Mike Patterson, who writes the North Coast Diaries blog, has a great piece on phenolongical variation across Oregon’s differing ecoregions.  It’s here  — highly recommended.

It was another night where the large scale impact of weather on migration is clearly on display.  So i threw in a National Radar Composite and a map of the winds at 850 mb heights (roughly 1500 meters).

For commentary on the migration through New England check out Tom Auer’s Blog.  Also, today he has some information on a new radar product coming out of NOAA.  It’s a product they are calling “Bioscatter“.  My guess it is the same algorithm, or a clone, that derives the Hydrometeor Classification images found at the College of DuPage’s weather site, and that i highlight here at times when separating birds from rain.  I have added it to the sidebar under the Weather section.  You’ll have to figure out how to access it by navigating their product menu.

10 Apr 2015 — PNW Migration Update

It was a Pacific Flyway party last night.  Heavy migration from San Diego to Seattle.  Birds definitely took advantage of the south winds associated with the leading edge of the incoming cold front.

I threw in a snapshot of the National Composite radar today for another look at the interaction of weather and migration.  With a big storm front draped across the central part of the country it is easy to see migration out in front of it and nothing immediately behind it.

A few more Purple Martin reports in the Portland area but that’s about it.  The big push is just around the corner as the Central Valley is loaded with migrants.

27 Mar 2015 — PNW Migration Update

Excellent night flight, and as i write this it is still at full tilt.

Only new migrant reported that i saw listed was Purple Martin on the southern Oregon coast.

But tonight is one of those teachable moments on the interaction of the weather and migration.  So we’ll look at the conditions at 850 mb heights — note the stream lines and the ridge in the west and the trough in the east.  Then check out the static image of the national radar composite.  (The full loop can be viewed over at Paul’s archive: here)

The Pacific Flyway from the Mexican border to the Canadian border is solid blue with birds.  Everywhere else?  Central and Mississippi Flyways — nada.  Atlantic Flyway? — just a tiny bit on the SE coast ahead of the advancing cold front.

Big picture gallery today.

29 May 2014 PNW Migration Update

Some rather unstable weather, WNW winds, it’s late in the season …. and still there is a sea of feathers overhead.  Well, maybe just a puddle, but impressive none the less.

As the high pressure ridge builds in behind our recent low we can expect the winds to shift to a more northerly component, but the skies should clear.  So it will depend on the strength of the winds tomorrow night to determine the magnitude of the last covered flight of the season.  I’m hoping the winds are light and the sky is filled with the remnants of the feathered travelers.  The past few nights i have regularly heard the nocturnal flight calls of Swainson’s Thrush – it’s comforting, and brings a bit of joy to my world.

Before we take a look at the loops: “Message Date: May 28 2014 15:26:44 KRTX MAY HAVE PERIODIC DATA LOSS TODAY FROM 28/16Z THROUGH 29/02Z DUE TO AN AWIP S UPGRADE AT WFO PORTLAND.”

I have no idea what that means and i don’t really see any problems in the loop, but some more discerning eye might so, there you have it.

29 May Base Reflectivity - Portland (KRTX)

29 May Base Reflectivity – Gray’s Harbor (KLGX)

29 May Base Reflectivity - Seattle (KATX)

Here is the grand view of the winds aloft from Earth:

29 May Earth: WPD at 850 mb

Here is Paul’s archived National Radar Composite from yesterday. Look at the wind map, and then the radar.

And here are the weather maps (click on any image to bring up a full gallery view)

28 May 2014 PNW Migration Update

Less than ideal conditions, but nothing extreme.  A light westerly wind and a few rain cells to dodge – that’s about it.  So the laggards continue to lay a line north.  Densities are dropping as we are on the last legs of the journey.

Pacific Northwest Radar: (Click on the links below to open the .gif files in a new window)

28 May Base Reflectivity - Portland (KRTX)

28 May Base Reflectivity – Gray’s Harbor (KLGX)

28 May Base Reflectivity - Seattle (KATX)

Here is the grand view of the winds aloft from Earth:

28 May Earth: WPD at 850 mb

Here is Paul’s archived National Radar Composite from yesterday. Look at the wind map, and then the radar.

And here are the weather maps (click on any image to bring up a full gallery view)

27 May 2014 PNW Migration Update

Winds are light and out of the west — no big deal.  Migrants continue to flow north and are now looking to fill in the remaining nesting sites.  “FOS” is a term of the past on the listserves.  In eastern Oregon a number of expected vagrants are taking up bandwidth as birders flock to Malheur NWR as surely as Buffleheads fly to Manitoba.

This will be the last week for updates this season — unless something mega turns up in the region.

Pacific Northwest Radar: (Click on the links below to open the .gif files in a new window)

27 May Base Reflectivity - Portland (KRTX)

27 May Base Reflectivity – Gray’s Harbor (KLGX)

27 May Base Reflectivity - Seattle (KATX)

Here is the grand view of the winds aloft from Earth:

27 May Earth: WPD at 850 mb

Here is Paul’s archived National Radar Composite from yesterday. Look at the wind map, and then the radar.

And here are the weather maps (click on any image to bring up a full gallery view)

22 May 2014 PNW Migration Update

Migration in the region last night was a bit reduced from yesterday.  It could be the north winds were slightly stronger and it could be we are running out of birds.  Probably a little of both.  You can see the intensity dropping across the country.  With a second report of Nighthawks it’s pretty much what you would expect.

Next migration update is planned for Tuesday 27 May. I’m taking off for a long weekend.

Pacific Northwest Radar: (Click on the links below to open the .gif files in a new window)

22 May Base Reflectivity - Portland (KRTX)

22 May Base Reflectivity – Gray’s Harbor (KLGX)

22 May Base Reflectivity - Seattle (KATX)

Here is the grand view of the winds aloft from Earth:

22 May Earth: WPD at 850 mb

Here is Paul’s archived National Radar Composite from yesterday. Look at the wind map, and then the radar.

And here are the weather maps (click on any image to bring up a full gallery view)

21 May 2014 PNW Migration Update

As the high pressure ridge moves ashore winds are out of the north.  Along the coast they are quite stiff and probably accounts for the paucity of coastal returns on the Gray’s Harbor (KLGX) radar last night.  But inland, the winds are light and the I5 corridor was lit up as the flight north continues.

Pacific Northwest Radar: (Click on the links below to open the .gif files in a new window)

21 May Base Reflectivity - Portland (KRTX)

21 May Base Reflectivity – Gray’s Harbor (KLGX)

21 May Base Reflectivity - Seattle (KATX)

Here is the grand view of the winds aloft from Earth:

21 May Earth: WPD at 850 mb

Here is Paul’s archived National Radar Composite from yesterday. Look at the wind map, and then the radar.

And here are the weather maps (click on any image to bring up a full gallery view)