The migrants are still trickling through, again mainly along the east side.
The bulk of the Greater White-fronted Geese appear to have moved on. I didn’t see any this weekend. No signs of the Snow Geese or Swans yet, but a few more ducks have turned up – Ring-necked and Lesser Scaup. All of the winter sparrows are firmly in place.
It may be getting a bit late in the season but it’s not over yet! The past few nights since the last update were pretty much repeats. Moderate to heavy migration with an east side bias. If you can make it up to a high Cascade Lake before dawn it’s a good time to catch the haunting calls of loons as the sun comes up.
One interesting artifact in this and the last loop are the cloud capped peaks of the Cascades. Rainier, Adams and Hood and just a hint of Helens stand out in the sea of green.
Take a look at the radar last night. Notice that the bulk of the migration is over on the east side, up over the Cascades. These are probably the divers moving south. Now is the peak time for finding loons, and grebes on the high Cascade lakes.
Weather conditions were ideal with a bit of a tail wind out of the NW, clear skies, and an urge to push south. Birds are on the move.
Watch the tail end of the radar loop below closely (Click on the gallery to bring up a screen size image). As the migrants thin out, but not quite put down, a small bright green flash appears along the Willamette River between Yamhill and Marion counties — Swallows.
It’s been a busy month for the migrants. A huge push of Greater White-fronted Geese last week. Cacklers are back in force and duck numbers are building, some even showing basic plumage. Shorebirds have probably peeked but are still on the move. Winter sparrows are in as are the Kinglets. Migrant summer resident breeders have moved out for the most part. Fall
Last night the high pressure system spinning up off shore drove northerly wind on a relatively clear night and the birds took advantage.
A fairly decent night of migration in the face of light crosswinds out of the east and upper level southerly flow. The bloom sticks mainly to the east side of the I5 corridor.
The .gif file below shows the dBZ reaching the 25 – 30 range indicating heavy, if not widespread, migration last night.
RTX Base Velocity 16 Sept 2014
On the Barn Swallow front; examining the past static images, and the one enclosed today, it appears there is actually three roosts taking off just after dawn. In today’s image i have highlighted the clusters just as they begin to rise and prior to dispersal.
Really not much happening on the broader migration front. Of note is that the Sandhill Cranes are back in good numbers out on Sauvie Island.
Today i have put together a quilt of images showing the Swallow morning fly-out on the Yamhill/Marion County border. I can’t slow the .gif files down and this goes by pretty fast. It takes about 45 minutes in total but that is covered in only 5 or 6 frames. You can always go to the COD weather website and control the image speed, but here it is in single frames stiched together. (i think my time marking may be off by 10 minutes or so)
Click on the thumbnail to bring up a larger image:
Well, it had to happen some time. The blog is running out of free disk space. So, posting from now on will be sparse and limited to a few Choice snapshots of each season.
Like last night and this morning. Excellent migrant bloom sustained throughout the night, with tracks up into the Puget trough. And — as a bonus — at 13:30 UTC (06:30 PDT) for four frames there can be seen the morning exodus of the swallow roost on the border of Yamhill and Marion Counties. It last for about four to six frames and the density is impressive. (Click on the thumbnail below to bring up a larger animated .gif file)
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)
Here is the grand view of the winds aloft from Earth:
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)