On the move . . .

Andrew Farnsworth The Cornell Lab Feb 13, 2013

Two interesting patterns may spice up the mid-February birding scene next week. High pressure building into the Southeastern US should bring a period of warmer, southerly flow to many areas of the Gulf Coast by Monday. These conditions may facilitate some typically early migrant songbirds and waterfowl to move on Monday night. Radar reflectivity values may show light and scattered migration from Texas north to Missouri and east to the central and southern Appalachians. Presumably, the composition of these movements will be early passerine migrants such as some sparrows as well as some waterfowl.

High pressure in the Southeast brings southerly flow and warmer temperatures to many areas of the Gulf Coast and Lower Mississippi River valley. These conditions may facilitate some light and scattered migration of early passerine migrants and waterfowl. Note, also, the low pressure center moving past the Canadian maritimes; this system may interact with the low discussed in the next figure to facilitate some shuffling of Arctic or European species into Maritime Canada or perhaps coastal New England.

Additionally, a deepening low pressure center moving across the North Atlantic may be associated with easterly flow to the North of its passage, particularly in conjunction with a second strong low moving past Newfoundland (see above). In a continuing consideration of the Eastern Promises we have been discussing for several months, the potential for some European vagrants to enter North American airspace probably exists during the coming week. As this is a rather isolated incident rather than a strong negative period of North Atlantic Oscillation index, the chances of a major European arrival in the New World are quite low. Regardless,┬ábirders in the Canadian maritimes and perhaps some areas of coastal New England should be watchful, particularly those in Newfoundland, for any odd waterfowl, shorebirds, gulls, and passerines to appear. Additionally, this pattern may also spur more typically Arctic species like Ross’s and Ivory Gulls to move, so keeping a close watch of gulls is probably warranted in these areas.

An enlarged map of the distribution of pressure centers in the North Atlantic. Note the easterly flow wrapping to the East and North of the strong low pressure center over the North Atlantic. Whether this easterly flow is strong enough to produce European vagrants remains to be seen, but birders in Northeastern North America should be watchful.