Upper level southerly winds, though not strong, along with a dwindling season, yielded very light migration over the region last night. Heaviest returns were in the Puget Sound area and those were moderate at best. San Diego is reporting their first Buffleheads, so you know it is pretty late in the season.
And with that — i’m headed into the field for the next three days and shutting down the blog for this season. I will monitor the radar, as all radar junkies do, and if anything interesting pops up i’ll post it. But barring that and conditions permitting, i’ll be back in the spring with the Turkey Vultures.
Ho Hum. Under superb conditions only a moderate flight across the region. Still plenty of birds in the pipeline but it looks like they will be trickling in over the next month. With such unseasonably warm and rainless weather perhaps there is no urgency to leave the northern realms. I’m seeing lots of bugs and even good numbers of dragonflies out in the field. The local unmanaged seasonal wetlands are dry as well. I’ll keep an eye out for a pulse, but this is a signature of a waning season that is being drawn out.
The high pressure ridge remains stable and the winds will be driven out of the north. Some temperature differential winds will be driving an easterly component, but mainly during the daylight hours. Clear skies for a few more days at least.
Migration ideal conditions remain in place and look to continue for a few more days.
Last night birds were again headed south in moderate numbers – heavy in patches, mainly inland. The first of the Buffleheads are being reported but not in any significant numbers. So we’re on the downhill side of peak migration – lots of ducks and late season migrants still in the pipeline. I was in the field yesterday for a bit and most noticeable was the increased numbers of Mudhens and lack of ducks.
This high pressure ridge continues to remain stable. It gets a bit disturbed 36 to 48 hrs out, but not much and looks to rebuild. Should be a glorious weekend with light winds mainly out of the north and clear skies — foggy mornings.
Most of the action was to our north, while the Portland/Vancouver Basin only saw moderate levels of migration last night. There were some pockets of heavy movement, just not widespread. However, along the coast and across the Strait, birds were heavily on the move. Maybe the localized rain dampened local spirits or they may just be happy to hang out for a while and enjoy our hospitality – we’ve got some really great bugs.
Whatever the case, it looks like some upper level instability will be moving into the area 24 to 48 hours out. Which may disrupt things a bit, but i don’t see any rain and the winds should remain out of the north. So we’ll see.
Tomorrow starts the weekend and i will be out in the field early. So updates, if any, will be for archival purposes.
Here are last night’s radar soundings from the PNW radars (left click will take you to the loop):
In spite of my Monday comments about shutting down early, i’m keeping the reports up until those Buffleheads show up like usual. This fall’s migration still has some legs.
Another night of excellent conditions and another night of birds on the move. From the US/CA border and down the I5 corridor birds filled the air space. We had some stronger winds out of the WNW that kept the birds inland – very few were out over the ocean last night.
Looks like we have another couple of days until the next significant low moves in. So we should see another good flight tonight.
With the discovery of the excellent (and i mean EXCELLENT!) weather site at the College of DuPage I have added one of their radar products to the loops – HCA. The HCA is explained in depth, with further linked resources, in a new page for the site. Look for it in the top banner with the other resources. But basically it is, “The HCA is a complex algorithm performed by the NEXRAD that attempts to determine the most likely type of the echoes in the radar beam.” And most importantly, for this blog, is that one of those echo types is classified as BI – biological. When you look at the HC loops note the scale on the right, look for the BI color, and get ready for your jaw to drop!
If you have ever wondered why the TV weather man has radar images up that do not show the birds — the HCA is the answer. They take the signal and eliminate unwanted echo classifications. Here are last night’s loops – (man, i am so f’n stoked to have these archived again!)
As the low passes through, the ridge continues to build in behind pushing the winds out of the north and bringing a flood of migrants. It was one of those signature nights the migrants wait for. Streaming across the Strait, torrents of birds along the coast, and a deluge down the I5 corridor. We are dripping with birds tonight!
A reminder about these links: The regional level loops will break in a few days, NCAR does not archive the images past that. Paul’s loop will remain in perpetuity — he’s like that. The forecast links are dynamic and constantly updated. That is; if you go to past posts and follow those links, they will look just like today’s link.
Peak Reflectivity (KRTX)
Peak Reflectivity (KATX)
Peak Regional Reflectivity
Winds Aloft at 850mb Heights
Geopotential and Vorticity at 500mb Heights
BONUS!! Left click and open the links below for full animated .gifs of the THREE regional Reflectivity Loops. Yes, THREE. Whereas NCAR does not archive the Langley Hill radar College of DuPage does. Not only that, but that is where the .gif downloads are from. Sweet, sweet, sweet!
I spent the weekend in the field, hence no weekend updates.
However, even with the great conditions migration levels were moderate with a few heavy pulses at best. I put peak radar returns in today’s gallery.
It looks like we’re winding this season down. Surely the neo-trops are long gone and we are now just waiting on the winter residents to complete the season. I usually wait for the first Bufflehead to show up before i close the fall season. But: another couple of days with a low trough draped over the region, only a hint of a ridge 48 hrs out, and modest returns over the weekend with ideal conditions — i’m closing this season early. I will continue to review the radar and if anything noteworthy pops up i’ll put that up.
But barring that — that’s all folks! Circumstances allowing, i’ll be back in the spring. Hopefully with a fix for the lost animated radar loops.
A better flight than i expected last night. Upper level winds were favorable and there was enough room between the storm cells for moderate levels of migration to take place. To our north the migration was even heavy at times. The Puget Sound was filled with birds as was the Washington coast. Too bad it’s only Thursday as some of us have to work. The next few days should be really great birding.
A note on these links: The regional level loops will break in a few days, NCAR does not archive the images past that. Paul’s loop will remain in perpetuity — he’s like that. The forecast links are dynamic and constantly updated. That is; if you go to past posts and follow those links, they will look just like today’s link. It sucks for archival information, but until i can recode my scripts it’s the best i can do for now. I’ve poked around and it looks like Python might be another avenue. I’ll see what i can do between seasons to hack around in yet another programming language.
With the winds easing up, but still out of the south, and the skies clearing, we had a moderate amount of birds in the air last night. Surface winds are not as influential as the winds aloft on migrating birds, and those winds are actually out of the north as this weak ridge advances.
It looks like we have one more low to get through before we get better conditions – maybe 48 hours out or so. I suspect the flight tonight will be a bit subdued but Thursday and Friday could be quite significant – depends on how many birds are left in the pipeline.