Light to moderate migration, primarily in California and the Desert Southwest early in the period, brought increasing numbers of Bell’s Vireo, Lucy’s Warbler, Yellow Warbler, and Bullock’s Oriole to the West, while slightly more extensive light to moderate movements on Sunday and Monday nights, including Blue-winged Teal, Eastern Phoebe, Blue-headed Vireo, Tree Swallow, and Pine Warbler among other migrants, highlighted the period in the East.
After a damp start to the period, portions of the region, notably from the central Mississippi Valley east to the Appalachians, saw light to moderate movements on Sunday night. These movements expanded in slightly more favorable conditions on Monday night, extending across the Appalachians to DelMarVa. But Tuesday night saw the return of unfavorable conditions to the region that persisted through the end of the period, with marginal winds and precipitation shutting down migration in many areas or limiting movements to minimal to light levels (for example in Virginia on Wednesday night or portions of Pennsylvania and New Jersey on Thursday night).
Scattered light to moderate movements were the norm for the first half of the period, reaching their greatest extents and intensities by Monday night. Less favorable conditions followed, and a low pressure system moving through the region kept movements locally light to moderate through most of the remainder of the period. The period ended with a return to more extensive movements from Texas to Florida, including some migrants arriving from Cuba.
Marginal and unfavorable conditions for migration dominated the region this period. Although migrants clearly moved into the region, most movements were locally light to moderate movements and widely scattered across the region, occurring in the Dakotas on Saturday night and the central and southern Plains on Sunday and Monday nights.
California and the Desert Southwest experienced light to moderate movements from last weekend into the beginning of the work week. Most of the remainder of the region experienced minimal to light movements for the duration of the period. Note, however, that portions of the Pacific Northwest experienced light movements, noticeably on Wednesday and Thursday nights.