[CT Birds] birds on radar

[Roy Harvey]

First, Nick Bonomo did a good post about using the radar last year.
You can read it here:
http://lists.ctbirding.org/pipermail/ctbirds_lists.ctbirding.org/Week-of-Mon-20070416/000977.html

As to sorting the birds from the weather, I found it takes some
practice.  Here is an example of watching a good migration night
start, though it will only be available for another day or two.  At
http://www.rap.ucar.edu/weather/radar/ choose Regional reflectivity,
End date of 06 May 2008, End time of 0200 UTC, and loop duration of 2
hours.  Then click on the map, on the letters just below Connecticut.

As you watch the radar goes from blank to a few scattered dots, to
pale blue, to dark blue, eventually getting some small bits of green.
Note how it appears to be done in donuts, intense areas around blank
spots.  The holes in the donuts are where the actual radar stations
are; the radar doesn't work well locally.  Also notice that some of
the donuts are fringed with lighter shades.  That too is the nature of
the radar, not of the birds being in the air or not.  And realize that
large blank areas could simply mean the radar for that area was not
operating.

Now go back and change the End date to 08 May 2008, leaving the End
time at 0200 and the duration at 2 hours, and click on the map again.
There is a big system of bad weather in the upper left side of the
map.  Note that it doesn't look anything like the donuts.  It is far
more chaotic, covers a wide area, and it MOVES from west to east.  And
as you can watch the weather system moving you can see the birds
appearing as if from nowhere.  Look at the two parts of the map and
you will start to learn what to look for.

If you use it for checking the weather too you will get more practice.
I use the same map to give me an idea on the weather, even when there
is no migration.  If I get up to a rainy morning, but the radar shows
it is clear to the west, I know that after it moves east things will
be dry.  It doesn't say anything about overcase, of course.

While we are on the subject, for wind information I go to
http://www.intellicast.com/National/Wind/Current.aspx?location=USCT0094.
Note that was for current winds, but there is an option there for a
Windcast too.

I hope that helps 

Roy Harvey
Beacon Falls, CT


On Thu, 08 May 2008 21:49:38 -0400, you wrote:

>As a new subscriber to this list, please tell me again how to detect 
>bird migration on this site, rather than weather.
>http://www.rap.ucar.edu/weather/radar/
>
>Thank you.......
>
>  ~Carol in Harwinton