Forecast and Analysis

Regional Migration Analysis: 9-16 May 2014

Andrew Farnsworth The Cornell Lab May 16, 2014

Continental Summary

Scattered moderate movements that began the weekend gave way to much more widespread moderate and even locally heavy movements in the West, while a pulse of moderate to heavy movements kicked off the first half of the week in the East before being muted somewhat by a strong frontal passage. Species on the move this week included Least, Western and Solitary Sandpipers, Black Tern, Olive-sided, Yellow-bellied, Willow and Alder Flycatchers, Swainson’s and Gray-cheeked Thrushes, Tennessee, Magnolia, Chestnut-sided, Blackpoll, Palm, Yellow-rumped, and Mourning Warblers among other parulids, Chipping, Clay-colored, White-throated, and White-crowned Sparrows, Rose-breasted Grosbeak, and Bobolink.


Scattered precipitation in the Pacific Northwest and northern Rockies kept many birds grounded to start the weekend, while coastal movements farther south and west were in full swing. Precipitation cleared out by Sunday night, beginning the first night of several with moderate coastal movements that eventually expanded to be widespread over many areas of the region. Some of these movements along the coast were locally heavy. Species on the move this week included Bufflehead, Semipalmated Plover, Dunlin, Least Sandpiper, Western Sandpiper, Long-billed Dowitcher, Vaux’s Swift, Willow Flycatcher, Cordilleran Flycatcher, Swainson’s Thrush, Cedar Waxwing, Northern Waterthrush, MacGillivray’s Warbler, Yellow Warbler, Green-tailed Towhee, Chipping Sparrow, Clay-colored Sparrow, and Golden-crowned Sparrow.

Great Plains

Moderate to heavy movements became increasingly widespread across the region over the first part of the weekend. Although scattered precipitation shut down movements locally, it was not until Sunday night that a more substantially organized frontal passage, including some intense storms, shut down movements in most areas. In the wake of frontal passage, movements were mostly light with some isolated moderate movements. Moderate and locally heavy movements remained scattered through the end of the period, with scattered precipitation muting movements in the eastern Rockies and border states. Species on the move this week included Stilt Sandpiper, White-rumped Sandpiper, Red-necked Phalarope, Black Tern, Rufous Hummingbird, Eastern Wood-Pewee, Bank Swallow, Cliff Swallow, Swainson’s Thrush, Ruby-crowned Kinglet, Prairie Warbler, Tennessee Warbler, Mourning Warbler, American Redstart, Magnolia Warbler, Chestnut-sided Warbler, Blackpoll Warbler, Wilson’s Warbler, Field Sparrow, Lincoln’s Sparrow, White-throated Sparrow, White-crowned Sparrow, Dark-eyed Junco, and Eastern Meadowlark

Upper Midwest and Northeast

A patchwork of conditions across the region over the weekend brought some moderate and heavy movements, particularly west of the Appalachians, and some precipitation and much lighter movements, particularly in the eastern Great Lakes, Ohio River valley, and New England.  By Monday night, with a more organized front moving through the region, moderate to locally heavy movements occurred in the southerly flow in advance of frontal passage in many areas. However, the frontal passage was not fast, and eventually precipitation associated with this passage shut down movements in many areas through most of the remainder of the week, with exceptions being movements in the far northwest and northeast of the region. Species on the move this week included Green-winged Teal, Solitary Sandpiper, Olive-sided Flycatcher, Eastern Wood-Pewee, Alder Flycatcher, Willow Flycatcher, Blue-headed Vireo, Red-eyed Vireo, Ruby-crowned Kinglet, Hermit Thrush, Gray-cheeked Thrush, Swainson’s Thrush, Tennessee Warbler, American Redstart, Magnolia Warbler, Bay-breasted Warbler, Chestnut-sided Warbler, Blackpoll Warbler, Canada Warbler, Wilson’s Warbler, Palm Warbler, Yellow-rumped Warbler, Swamp Sparrow, White-throated Sparrow, Dark-eyed Junco, and Rusty Blackbird

Gulf Coast and Southeast

Frontal precipitation bisected the region to start the weekend, with mostly moderate movements to its west and scattered light to locally moderate movements to its east. But the remainder of the weekend saw more widespread moderate to heavy movements expand first in western portions of the region and then in the southeast and Florida Peninsula. This pulse was relatively short-lived, with a new frontal passage on Monday night and subsequent frontal stall keeping movements isolated and light to moderate. By the end of the period, moderate to locally heavy movements returned to Texas and portions of Louisiana, while most areas east of the Mississippi River stayed quiet. Species on the move this week included Solitary Sandpiper, Black Tern, Yellow-billed Cuckoo, Olive-sided Flycatcher, Western Wood-Pewee, Yellow-bellied Flycatcher, Alder Flycatcher, Willow Flycatcher, Cliff Swallow, Veery, Gray Catbird, Cape May Warbler, Blackpoll Warbler, Palm Warbler, Yellow-rumped Warbler, Mourning Warbler, Canada Warbler, Clay-colored Sparrow, Savannah Sparrow, White-throated Sparrow, White-crowned Sparrow, Scarlet Tanager, Rose-breasted Grosbeak, and Bobolink.