CObirders, Tonight, on the Front Range of CO, expect a cold frontal passage around sun-down (depending on your location). Here is what that looks like in 850mb winds at 6pm this evening (green circle is Longmont, CO)
https://earth.nullschool.net/#2021/08/29/0000Z/wind/isobaric/850hPa/orthographic=-98.48,41.12,712/loc=-105.120,40.191 With that passage, I expect to see turnover of the birds already being seen today. I don’t expect many of the goodies to stick around with the passage of this front, but if the food source is good, birds can stick around longer to fuel up. It isn’t just about birds leaving the area though, I expect to see a nice for this time of year push of migrants. Birds won’t be coming from very far away with this specific push (Montana seems to be the origin or our winds), but we’ll see what comes with it. Here is a good representation of the origin of the winds for this coming push (map is for midnight; green circle is Longmont, CO): https://earth.nullschool.net/#2021/08/29/0600Z/wind/isobaric/850hPa/orthographic=-99.91,47.44,712/loc=-105.120,40.191 The front is going to stall out overnight, which is great for birders near the location of the frontal stall. Here is a good representation of where the front is going to stall (4am map; green circle is between Walsenburg and La Junta) https://earth.nullschool.net/#2021/08/29/0900Z/wind/isobaric/850hPa/orthographic=-102.86,38.28,1207/loc=-103.904,37.565 Those of you birding in that area on Sunday have a nice chance for a build up/convergence of migrants. There is a good chance this includes Pueblo, any playas between Pueblo and Kit Carson, and possibly out toward John Martin and NeeNoshe reservoirs too depending on where the front really ends up stalling. David Tønnessen is leading a shorebird field trip out there tomorrow for CFO Shorebirds Workshop, so best of luck to them and anyone else going that direction. If anyone heads that direction tomorrow, try to find places where the winds are generally from the north rather than the south and you will be on the correct side of the front for migrants. Local effects from lakes can alter the wind field, so try to pay attention to the winds away from the lakes, not right next to them. Get out tomorrow to enjoy the birds and slightly cooler weather. We won’t be free from the smoke, but the cooler temperatures should make for happier birding conditions (cooler birders, *less* water shimmer, but still present). If you are right near the front tomorrow, you might expect some showers later in the day. Enjoy the cooler temperatures and lovely migrants. Bryan -- Bryan Guarente Meteorologist/Instructional Designer UCAR/The COMET Program Boulder, CO -- -- You received this message because you are subscribed to the Google Groups "Colorado Birds" group. To post to this group, send email to cobirds@googlegroups.com For more options, visit this group at http://groups.google.com/group/cobirds?hl=en?hl=en * 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/CFO/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+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/cobirds/CAENnWHvSbvxa2WjgZDzH9bYSWt3%3D8Hn8aCw%2B_-euQny3Bk1fFg%40mail.gmail.com.
