What's the Best Day to Go Hawk Watching in the Fall?

This is a common question, but unfortunately, the only possible answer to it is "It depends." Whether a particular day is likely to produce lots of migrating hawks depends on weather conditions both here and to the north of us, and the way the flight has developed so far.

The best advice we can give is to watch the weather reports and look for the passage of a cold front followed by northwest, north or northeast winds. The first and second days after a cold front passes during the fall are likely to have good flights of migrating raptors visible from hawkwatch sites (or maybe even your backyard).

If your goal is to witness the grand spectacle of thousands of migrating Broad-Winged Hawks, you want to look for a day with these weather conditions roughly between the 10th and 20th of September. Unlike most other species of hawks, the entire population of broadwings vacates the northeast around the same dates every year. In 25 years of observations, EMHW watchers have seen 90 percent of their total broadwing count between September 10 and 20 -- a time period often referred to as the "Broad-Wing window."

Whether a particular day during that period will produce a big show depends entirely on how far the birds have progressed on their migration by that time, and if winds and weather have transpired to concentrate them and send them past one of our watch sites within range of our optics. Using 8X binoculars, an observer can pick out a bird the size of a Broad-Winged Hawk passing not much further than a mile away. It's entirely possible to have a massive hawk movement through the area without anyone being aware of it.

More people go hawkwatching on the first weekend in the middle of the broadwing window than at any other time, looking for virtual "rivers of hawks." However, good numbers of hawks may be seen well almost anytime between early September and mid-November with preferable weather conditions. Remember that hawks are more likely to be seen in good numbers on a weekday, rather than a weekend. (There are only two days on a weekend!) Don't be afraid to go hawkwatching on a weekday in the middle of September, or any other fall month with favorable weather.

Eastern Massachusetts Hawk Watch, 2008
To contact EMHW, email
EMHW, PO Box 663, Newburyport, MA 01950
updated 07/20/2008