Migration over the Mid-Atlantic

We've got some interesting weather shaping up for the next week, but first I'll recap the last few days.
High pressure has dominated the Mid-Atlantic over the last week originally producing strong southeasterly winds and very little migration. Since Thursday, though, a stationary front has stretched from west to east across NY and PA, and moderate westerly winds have built in along its border. The west winds have brought some birds in from the Northwest over the last two nights, and some good birds have shown up in the region, such as an immature Ruff and a Calliope Hummingbird in Cape May.

Short-term forecast

As of today that stationary front will become a cold front, and work its way south over the region, bringing north winds to our area which will undoubtedly cause heavy migration from the northeastern US into the mid-Atlantic. The real question, then, will be how far the front will move before migration begins, and whether it will drift back north (as it is forecast to do) during the night as birds are migrating. These situations can be very interesting for migration, because a front which backs into oncoming birds can cause widespread fallout conditions along the frontal boundary, especially when accompanied by precipitation and a wind shift. Tonight's front is not expected to pack any precipitation, so the chance of fallout is low, although the chance is good that high densities of birds will enter the region and be pushed to the coast by westerly winds associated with the backing front.

Long-term outlook

This front should dissipate by Monday, and high pressure will again dominate the area, bringing with it south and west winds into mid-week. A strong cold front is forecast to enter the region Wednesday evening, and with it another big push of birds. This one looks like it'll bring some precipitation as well, so we'll have to revisit our predictions as mid-week approaches, in order to forecast any possible fallout conditions.

In the meantime, there are lots of good birds around- so get out there and bird!

Cheers

David (www.woodcreeper.com)