Forecast and Analysis

Regional Migration Analysis: 2-8 August 2013

Andrew Farnsworth The Cornell Lab Aug 09, 2013

Continental Summary

The West experienced primarily light movements, particularly toward the Pacific Coast and over the Desert Southwest, while the East experience light to moderate movements, primarily along a corridor from the northern Great Plains South and East toward the Gulf Coast.

Please note, we have posted two animated maps in this analysis because the typical University of Wyoming (directly below) feed did not capture all of the appropriate images at our desired 0400 and 0500 Z times; despite not having the front overlays of Wyoming mosaics, the UCAR map (bottom of this post) contained all of the relevant images needed to assess the week’s migration.



Away from scattered precipitation in the northern and central Rockies. scattered light movement began the forecast period. This was particularly evident in portions of the Desert Southwest and along the Pacific Coast. This pattern continued throughout the forecast period, although precipitation spread to a more diverse array of locations across parts of the mountainous West, shutting down movements where and when it occurred. Highest densities occurred in central California toward the middle of the week. Birds on the move this week included Pectoral, Solitary, Spotted, Least, and Baird’s Sandpipers, Red-necked Phalarope, Wilson’s, Black-throated Gray, and Orange-crowned Warblers, Lazuli Bunting, and Savannah Sparrow.

Great Plains

Primarily light movements were the norm in the northern Plains states to begin the period, as more southerly locales got soaked by heavy rain and intense storms. These movements continued for the week, interspersed between bouts of precipitation moving across the region. By late in the forecast period, slightly larger movements were occurring farther south in the Great Plains, particularly Nebraska and Kansas.┬áBirds on the move this week included Black-bellied Plover, Pectoral and Buff-breasted Sandpipers, Wilson’s Phalarope, Franklin’s Gull, and Black Tern.

Upper Midwest and Northeast

Light movements were widely scattered across the region this week, with  local moderate movements in the western reaches of the region from the western and central Great Lakes South through the central Mississippi River and East southern Ohio River valleys. Two primary pulses of movement occurred in these areas, first beginning Saturday and second beginning Wednesday. Birds on the move this week included Green-winged Teal, Semipalmated and Black-bellied Plovers, Lesser Yellowlegs, Whimbrel, Pectoral and White-rumped Sandpipers, Black-and-white Warbler, American Redstart, Northern Waterthrush, and Bobolink.

Gulf Coast and Southeast

Light to moderate movements began the period, followed by another pulse of migrants on Monday. Outside of these pulses of movement, light movements were the norm, primarily in the southeastern US but also in Texas and Louisiana airspace. Birds on the move this week included Sanderling, Upland, Solitary and Pectoral Sandpipers, Ruby-throated Hummingbird, Eastern Kingbird, Barn Swallow, Yellow-throated and Prairie Warblers, American Redstart.