Migration weather: next two days (5/1 - 5/2)

[Bryan Guarente]

COBirders,

An astute weather-watcher asked what it was going to look like for birds with the next system coming in. They were ahead of my thinking for sure (darn work getting in the way of fun). 

5/1 SE CO will see a connection from the Yucatan

https://earth.nullschool.net/#2022/05/01/1200Z/wind/isobaric/850hPa/orthographic=-100.03,32.69,1951/loc=-103.708,37.700 (Green circle is south of La Junta)

That map is quite telling of all of the overnight hours tonight.  That pattern doesn't look much different if you spend some time flipping through the times available on the wind maps from sundown tonight to sun-up tomorrow.  So this is a long duration convergence pattern which is a GREAT thing for SE CO.  Anywhere from Pueblo to Lamar (better towards Lamar than Pueblo) could see some great movements into the area overnight.  I also don't expect anything to leave the area from previous days, so we could see a large diversity of birds (even higher than already going on).  For the rest of CO tomorrow (Sunday), there won't be much movement of passerines overnight.  Expect though that this will change throughout the day on Sunday.  The connection from the Yucatan actually opens up throughout the day tomorrow and the northern Front Range gets in on the action!

5/2 Northern Front Range gets connected to the Yucatan

https://earth.nullschool.net/#2022/05/02/1200Z/wind/isobaric/850hPa/orthographic=-98.23,34.96,1951/loc=-105.120,40.191 (Green circle in Longmont for reference)

I expect that the northern Front Range will be the target on Monday after SE CO's good chances.  The problem with Monday is the chance of rain throughout the area.  This will make the birding maybe a bit more hit or miss location-wise.  But that won't likely matter too much because the birds WILL be on the move.  It may just be hard to guess the exact location of the best birding Monday morning due to the possible rain.  But, get out there and find the best spots and let everyone else know.  We'll be watching.

Now, this actually brings up another point.  With the chance of rain, this will mean the cloud cover will be lower, so overnight migrant listening might be really good for CO standards.  Low cloud cover drives the birds to be lower towards the ground, making calls easier to hear, and with the winds coming from the Yucatan, we have a good chance of getting some good night flight calls as long as it isn't raining where you are.  

And finally, if you haven't believed me for all these years, or you need more supporting information, you can check out birdcast's new "Migration Dashboard" for every county and state in the US.  https://birdcast.info/migration-tools/migration-dashboard/. This brand new website shows you estimated numbers of birds from real-time radar data over your county or state of choice.  Enter your county or state into the text field and press "Search".  This will take you to a page where you can monitor the radar-estimated bird counts over your area.  There is a nice archive to dig through as well to see how migration has been playing out recently compared to historical numbers.  This page has been quite instructive over the past couple weeks since it went live.  If you want to see more about the dashboard you can check out the recorded webcast about the new dashboard here: https://academy.allaboutbirds.org/live-event/the-birdcast-dashboard-live-radar-tracking-of-bird-migration-in-your-county-and-state/

May the winds be ever in your (and the birds') favor.

Bryan

[Bryan Guarente]

Wow!  Right now (6am) on 5/1, there is what looks like a large mass of birds on the Pueblo radar headed northwest. If you are El Paso or Pueblo counties, get out near the gray oval of possible birds and see what you can find: 

https://weather.cod.edu/satrad/nexrad/?parms=PUX-N0Q-0-96-100-usa-rad. This link is best viewed from a desktop computer not a mobile web browser. 

Note this is a live updating link so if you click it too long after this email, you may not see the gray oval headed northwest. 

Exciting times!

Bryan

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Bryan Guarente

Meteorologist/Instructional Designer

UCAR/The COMET Program

Boulder, CO