No Migration Detected

Winds out of the Southwest seem to have kept much from happening last night. Some small signature is seen after sunset but dissipates by midnight, possible due more to atmospheric causes. Below is some information provided by Greg Thompson (the Guru behind the ncar website).

Greg wrote:
” Don’t forget that some echo comes from insects not always birds (though the two often go
hand-in-hand – food chain thing) AND, MORE IMPORTANTLY, that
some echo comes from A.P. (anomalous propagation) whereby the
radar energy is scattered by a large difference in air density
then off the actual terrain surface before being measured at
the radar site. This type of echo is probably hard to tell from
birds/insects under the right circumstances. That air density
difference can arise when the nighttime inversion starts to
occur which is why the radars all light up at sunset from
east to west and vice-versa at sunrise. “

©2004

Bird on the Move

Look at that radar light up! Here’s a national composite (click the image to see the animation)…look at how the radar stations light up just after sunset, moving west with the setting sun. The last image is from about 10:30pm. Birds are moving all across the country! (all the dark blue circles that “appear” in the animation represent birds reaching altitude enough for the radar to detect them).
©2004
The image below is from 7pm last night until 6:30am this morning. It looks like there were some birds over the water after sunrise.
©2004

Small Migration Evident

Here’s the image from this morning. The image includes the entire loop, from sunset last night to 7:00am this morning. Birds are seen entering the radar after sunset, moving southwest, and then being put down by the weather as it moved northeast. Since the movement was light I don’t expect any major fallout conditions, although whatever birds were moving are likely concentrated along the edge of the weather event.

click the image below to see the animation:
©2004

Birds lifting off from New Jersey (PM)

With little to no wind over the state, some birds are on the move tonight. Overall it doesn’t look too impressive, but there are birds moving nonetheless. The cold front that was expected this weekend never made it, and a trough of warm wet air lingers on the east coast (you can see it in the radar). What birds will do east of the front and west of the trough will likely determine what we see in the next few days. The cold front is expected to make it across our area sometime on Wednesday, but that always up in the air…we’ll have to wait and bird, er, see.

This image is from just after sunset today until around 11pm. Click the image below to open the animation.

©2004