Mike Preston's report card in Week 3
The Baltimore Sun

Bird deaths: Did NWS radar capture startled flock?

Weather radar in Little Rock, Ark. may have captured an image of a flock of birds as they rose from nighttime roosts near Beebe, Ark. on New Year's Eve. Thousands of redwing blackbirds were later found dead on the ground nearby.

Such radar images of bird flocks are not unusual. Weather radar sites near the Chesapeake Bay in Maryland and Delaware sometimes capture the radar reflections of flocks of birds as they rise into the sky at sunrise on summer mornings.

Last night, Steve Zubrick, the science officer out at the National Weather Service forecast office in Sterling, Va., sent me a link to a radar image recorded beginning at 10:21 p.m. Central Time in Little Rock. That's about a half hour before reports began coming in about dead birds falling from the sky in Beebe.

The loop shows rainstorms moving away to the north and east of the radar. But at a spot about 25 nautical miles northeast of the radar, an unusual reflection appears, expands and moves off to the southeast with the prevailing winds. It's the green blob on the still radar image above.

"Could these returns be birds disturbed from the nightly roosting sites?" Steve asks.

"Given what was on radar...just a few light showers moving NE and examination of surface obs within 30nm of this area showed nothing unusual (no high wind gusts, eg). There were a few positive lightning strikes about 50-55 nautical miles to the SE over Arkansas County around 0430 UTC. Positive lightning strikes carry much more current then negative strikes...and have a much bigger "boom" then negative strikes. Still, they were located 55 miles away...although it would not be entirely impossible other lightning (non-cloud-to-ground) could have occurred.

"But I don't have any data that could show that (i.e., there is no lightning detection network that I know of in that area that would pick up the "total" lightning (e.g., within cloud or cloud-to-air)

"I'd say there is not a meteorological explanation. Exploding fireworks sounds like the most plausible...given the time of year...New Year's Eve...and that many folks like to shoot off fireworks to celebrate the New Year."

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