Updated: April 2, 2008 @ 11:23 AM
Winds have switched around to the NW overnight, so no migration is expected for this evening. The Wednesday Night/ Thursday Morning forecast has been removed to reflect this switch. A new forecast for the rest of the week will be posted by Thursday afternoon. Hopefully you're out there finding the migrants that showed up last night/ this morning!
Good Birding - DLP

As promised, migration is really picking up as of tonight. A powerful low pressure system is moving slowly northeastward across the Great Lakes, setting up a strong southerly wind gradient as it approaches the east coast. Favorable winds coupled with the prospect of rain each night are tempting me to cry "FALLOUT!"... but I will restrain myself, as It's still early in the migration season and birds aren't desperate to migrate as of yet. Still, we could see some of the first large-scale migration over the next two nights, so read the forecast below, clean off your binoculars, and get ready to bird.

Migration Weather Forecast

Tonight

Low pressure over the Great Lakes and high pressure off the eastern seaboard are creating a strong southerly wind gradient over the Mid-Atlantic. Tonight expect southeasterly winds at the surface, with strong southerly winds around 3000 feet which, together, will definitely trigger migration over the region. Winds are expected to be southerly over Virginia and the Carolinas, which will really help bring new birds into the Mid-Atlantic for Monday morning. Rainfall tonight should be light which reduces the chance of a localized fallout, but be sure to check the radar in the morning to be sure a thunderstorm didn't pop up in yout area during the night.

Tuesday Night

By Tuesday night low pressure will have moved east into Quebec, shifting the wind direction to southwest, and creating a direct trajectory from the Gulf Coast up into the Northeastern US. Again, precipitation is forecast for Tuesday night with an increased chance of late-night thunderstorms. This type of precipitation has the potential to cause localized fallout conditions, so keeping an eye on the weather will be imperetive for choosing the best birding location on Wednesday morning.

Wednesday Night

By Wednesday night the low pressure system will have pushed into Newfoundland, and high pressure will build in behind the front, turning the winds around to the WNW. Should the winds remain more westerly, and given the forecast for strong southerly flow up the central flyway, we could see typically western species being redirected to the east coast, although this type of prediction is much less... well... predictable. Alternatively, if the winds remain northwesterly we can expect a halt in migration until the next front makes its way to the east on Friday.

Birding Forecast

Tuesday Morning

Southeasterly surface winds will favor inland locations such as the northern Delaware Bay shore (NJ), the Delaware River floodplain (PA and NJ) and Garret Mountain (NJ). Because of the chance of precipitation it will be a good idea to check the radar in the morning to see if and where birds were forced to land due to weather.

Wednesday Morning

The wind-shift to southwesterly will favor coastal locations across the mid-Atlantic, such as Sandy Hook (NJ) and Cape May (NJ). With thunderstorms possible it will be important to check the radar to determine if and when birds were forced to land. Since winds will be strong, birds may overshoot the coast and therefore we could experience late-morning fallouts at coastal locations. Hopefully the southwesterly flow will bring more southerly migrants to the region and increase the chance of a western vagrant species.

Thursday Morning

While not as easy to predict, the strong westerly winds forecast for Wednesday night could lead to more displaced western birds by Thursday morning (although the probability is quite low given how early it is in the spring). Otherwise, if the wind switches to the northwest, migration will likely shut down until the next cold front approaches our area on Friday.

I'll update this forecast on Wednesday afternoon, but in the meantime you can find me on www.woodcreeper.com each morning interpreting the radar. For information on what's being seen TODAY in Cape May, check out the View From the Cape, on BirdCapeMay.org