Date: 9/10/17 6:42 am From: Paul Sullivan <paultsullivan...> Subject: [obol] Re: Barn Swallow fly-out Sunday morning
At 6:35 I see the first green dot
At 6:38 - bigger green dot with yellow center. The fly-out has begun.
From: Paul Sullivan [mailto:<paultsullivan...>] Sent: Sunday, September 10, 2017 6:23 AM To: <obol...>; <YamhillBirders...>; <birding...> Subject: Barn Swallow fly-out Sunday morning
I'm set-up to watch the fly-out of Barn Swallows from the Grand Island roost this morning. Looking at the Weather Underground image of Portland radar I see that the sensitivity of the radar is set to a broader range +5 dBZ to +75 dBZ, so the lighter image of the swallows must compete with heaver rain in the Cascades. However, it is not raining at Grand Island, so the radar signature of the birds should be visible.