New York and Philadelphia Bird Migration Forecast: 28 September – 5 October 2012

The coming week will see rapid changes as several systems alternately shut down and spawn substantial passages of birds through the region. These movements, when they occur, should include the first substantial, primarily sparrow movements, including White-throated, White-crowned, Savannah, and Chipping Sparrows, as warbler numbers diminish. Rain shuts down migration to end the week, but a wind shift on Friday 28 September night may bring new migrant into the Philadelphia area by Saturday morning. Depending on the extent of this passage, local parks may be quite birdy in locations from Philadelphia east and north into New Jersey, to migrant traps along the Delaware River and isolated traps like Garrett Mountain. This movement may affect areas as far east as New York, so birders should be out listening if skies are overcast but mostly rain free! The effects of this wind shift will not last long – moderate movements north and west of New York and locally heavy movement in the New Jersey and Philadelphia areas on Saturday night suggest Sunday will be a good day for birding. However, much less favorable conditions follow almost immediately to begin the week. Clear skies and westerly and northerly flow on Monday 1 October will spawn locally heavy movements over the metro areas, with Tuesday morning a good morning to rise early and watch the immediate coast for birds migrating along the barrier beach. Time spent at Sandy Hook, NJ and Jones Beach and Robert Moses State Parks on Long Island’s south shore, should yield nice flights of songbirds, including continued, typically sporadic migrants through the area like Purple Finch and Red-breasted Nuthatch, as well as the first more substantial numbers of later migrants like sparrows, Rusty Blackbirds, and of course Merlins coursing along the barrier beaches. More rain and southerly winds on Tuesday night and through Wednesday shut down movements, but clear skies and stronger northwesterlies bring another heavy flight on Wednesday 3 October night. Depending on the strength of the winds associated with these frontal passages, numbers of birds could fluctuate substantially from coastal to inland locations. Stronger winds tend to suggest a run to coastal habitats, whereas weaker winds speak to birding inland locations. Regardless, the late week migrant scenario looks to deteriorate to end the forecast period, with a migration shut down in more widespread rain forecast for later on 4 October.