9/1 IL Migration Report

Hey there!

Winds south of the cold front in IL are less ideal for
migration...conditions will improve throughout the state as it
moves south, bring northwesterly winds with it.

Tonight, we watch not only as a large cold front and corresponding storms move southeast, but also as northwesterly winds--and strong ones at that--move into our area. These winds, trailing in the momentum of the cold front, are very good new for migration...north of the front where winds are in effect, we're getting moderate to heavy movements of birds, which means tomorrow could be a very productive labor day. Expect more warblers, flycatchers, and thrushes to arrive and influx, but also vireos, perhaps kinglets, and of course more shorebirds. Raptors, if it's not cloudy all day tomorrow, is also a very reasonable goal. Make your own predictions as to what will arrive/influx here: http://bit.ly/17nhLgM - note that most warbler species peak fall migration month is September.

Migration at the time of this post. 

Notice that movements are heavier 

north of  the front (See image  above), 

than below,  where winds are less

 ideal for migration. Click to 

enlarge.

The news gets better in the wind forecast. Northerly winds are forecast to continue at least through midday Tuesday in much of the state, so tonight may be the first night of a couple of days of substantial migration.

To see the magnitude of tonight's migration, check out this live flash animation of the radar: http://bit.ly/17tyHz1 - the column of lines moving west represent the sunset. The more green in the blue, donut-shaped forms, the denser the migration of birds.

The division between winds north and
south of the cold front is very clear.
Click to enlarge

Good stuff! Happy birding everyone.