There is a convergence zone just to the south of Hale, CO in that wind
field. This is possibly in the wrong spot due to resolution issues in the
GFS (ask about it some other time if you are interested). What I believe
is going on with the 850mb winds is accurate, just slightly imprecise. The
convergence zone should be slightly further north. And if that is the
case, then Hale would be a good epicenter for where there should be a ton
of birds getting funneled into.
Jumping back a few hours:
https://earth.nullschool.net/#2025/05/24/1100Z/wind/isobaric/850hPa/<orthographic...>,36.58,2053/<loc...>,39.631 (5am May 24th), you can see that the same situation was there and the
convergence line was much more in line with Hale. Everything in the orange
outline (hand drawn, so not super accurate), should end up in the area
around Hale and if this happened for multiple hours, then you have a really
crazy good situation to get LOTS of birds in one place.
[image: Screenshot 2025-06-10 at 11.37.13.png]
So this was a great time of year for Orchard Oriole migration, a great
weather situation to get the birds to Hale, great idea to go birding out on
the eastern Plains, and probably some luck to be at the right place at
the right time. Congrats!
Bryan
Bryan Guarente
Meteorologist/Instructional Designer
UCAR/The COMET Program
Boulder, CO
On Mon, Jun 9, 2025 at 5:19 PM Luke Pheneger <phenegerluke...> wrote:
> Hi all,
>
> This is a long-overdue report, but I wanted to share an incredible
> phenomenon that Will Anderson, Nathan Pieplow, and I observed in Hale,
> Colorado this May.
>
> On May 24th we arrived early to the Hale Crossroads eBird hotspot in hopes
> of finding some late season migrants. It was a cold day barely reaching
> over 50 degrees, with intermittent sprinkles, and fog. We had a fairly
> active morning, turning up good numbers of Swainson’s Thrushes, a few
> silent Traill’s Flycatchers, a Veery, Northern Waterthrush, some Yellow
> Billed Cuckoos, and even a singing male Hooded Warbler, but these are not
> the topic of this post.
>
> Oftentimes it seems as though a visit to any open location with trees in
> the far eastern part of the state is likely to turn up Orchard Orioles, and
> today was no exception. Most parts of the property hosted a few singing
> males and small flocks, but we weren’t prepared for what we were about to
> witness. As we walked along the county road back to our cars, heading to
> our next location, we noticed a small flock of 6–8 passerines flitting
> around a modestly sized tree, what species I cannot remember. While we were
> trying to get an angle to identify them, suddenly, 10 Orchard Orioles flew
> out from the tree, crossed the road, and vanished into the forest—an
> impressive sight on its own. However it did not stop there, one by one
> Orchard Orioles kept flying out, first it totaled 20, then 30, then 40, 50,
> 60 not stopping until we had seen 96 Orchard Orioles fly out of the single
> tree. As we continued down the road, we began to see and hear even more
> Orchard Orioles scattered about that we hadn’t yet counted. By the end of
> our visit we had determined that we had come across approximately 145
> orchard Orioles at the property. The previous state high count for this
> species on eBird was in the 70s, recorded by Steve Mlodinow, an impressive
> total in its own right!
>
> I don't really have any conclusion to this story as this was likely the
> result of a weather-induced fallout, but I wanted to share the experience
> nonetheless. If anyone else has noticed anything like this anywhere else
> with this particular species I’d love to hear about it.
>
> Good Birding,
>
> Luke Pheneger
>
>
> --
> --
> You received this message because you are subscribed to the Google Groups
> "Colorado Birds" group.
> To post to this group, send email to <cobirds...>
> For more options, visit this group at
> http://groups.google.com/group/cobirds > * All posts should be signed with the poster's full name and city. Include
> bird species and location in the subject line when appropriate.
> * Join Colorado Field Ornithologists https://cobirds.org/membership/ > ---
> You received this message because you are subscribed to the Google Groups
> "Colorado Birds" group.
> To unsubscribe from this group and stop receiving emails from it, send an
> email to cobirds+<unsubscribe...>
> To view this discussion visit
> https://groups.google.com/d/msgid/cobirds/CALhMPZfP9wJhj7XpBHNZJqJbyFG0x%<2Bo1MUGB1GGnkF_hLXg7Yg...> > <https://groups.google.com/d/msgid/cobirds/CALhMPZfP9wJhj7XpBHNZJqJbyFG0x%<2Bo1MUGB1GGnkF_hLXg7Yg...>?utm_medium=email&utm_source=footer> > .
>
--
--
You received this message because you are subscribed to the Google Groups "Colorado Birds" group.
To post to this group, send email to <cobirds...>
For more options, visit this group at
http://groups.google.com/group/cobirds * All posts should be signed with the poster's full name and city. Include bird species and location in the subject line when appropriate.
* Join Colorado Field Ornithologists https://cobirds.org/membership/ ---
You received this message because you are subscribed to the Google Groups "Colorado Birds" group.
To unsubscribe from this group and stop receiving emails from it, send an email to cobirds+<unsubscribe...>
To view this discussion visit https://groups.google.com/d/msgid/cobirds/CAENnWHv%<3DSNhBxzJCrqUrFrQWAiWa_uCJuNiPaDP68Y8keQVDXw...>
