Usually a light northwest or Northeast wind is best for observing a large broadwing migration on Putney Mountain. Once you get into October, a strong northwest wind is best for observing the falcons, and large raptors.  
The next day that is partly sunny with slight north winds (or no wind at all) should produce quite a massive flight of broadwings up on Putney Mountain. No hawks have been able to fly for past three to four days (due to rain and south winds). This will hopefully produce a good flight when they eventually do fly. 
With all that said, hawks never read the weather report, and sometimes fly when you least expect it! Your best bet is to get down to Putney Mountain as often as you can in the next week and half and you should hit a decent migration day. 
 Good birding. Taj

Taj Schottland
Putney, VT
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