Forecast and Analysis

Regional Migration Forecast: 15-22 August 2014

Andrew Farnsworth The Cornell Lab Aug 16, 2014

Continental Summary

A patchwork of marginal and locally favorable conditions bring scattered light to moderate movements across the continent this week. Species on the move this week will include Green-winged Teal, Black-bellied Plover, Solitary Sandpiper, Upland Sandpiper, Least Sandpiper, Olive-sided Flycatcher, Yellow-bellied Flycatcher, Wilson’s Warbler, Canada Warbler, American Redstart, Black-and-white Warbler, Yellow Warbler, and Bobolink.

Arrows show wind speed and direction (arrow points in the direction to which wind is blowing) 100 m above ground level. Areas with southerly winds are colored red; northerly winds colored blue. Accumulated precipitation (in 6 hour intervals) is green, outlined by white. Broadly speaking, areas of the map in red will experience conditions that are favorable for migration, and areas where red and green (and red and blue) intersect and overlap may experience migrant concentrations and fallouts as migrants interact with precipitation.


Scattered marginal to locally favorable conditions will be the norm across the region for this week, with light to moderate movements occurring in many areas where these conditions occur. However, precipitation is forecast for many areas over the course of the period and will shut down migration where and when it occurs. Saturday, Sunday, and Monday evenings will see the greatest extents of movements, from portions of the Pacific Northwest east and south through the central and eastern Rockies. Species on the move this week will include Wilson’s Warbler, Nashville Warbler, Green-winged Teal, Lesser Yellowlegs, Northern Shoveler, Red-necked Phalarope, Yellow Warbler, Baird’s Sandpiper, Townsend’s Warbler, Orange-crowned Warbler, Solitary Sandpiper, Least Sandpiper, Upland Sandpiper, and MacGillivray’s Warbler.

Great Plains

Although portions of the weekend will see marginal and locally favorable conditions in some areas of the northern and central Plains, most of the forecast period will be dominated by unfavorable conditions including strong southerly winds and precipitation. Where and when migration occurs, it will be light to moderate. Species on the move this week will include Olive-sided Flycatcher, American Redstart, Northern Harrier, Ruby-throated Hummingbird, Wilson’s Warbler, Baltimore Oriole, Loggerhead Shrike, Least Flycatcher, Blue Grosbeak, and Black-and-white Warbler.

Upper Midwest and Northeast

An area favorable for light to moderate movements begins the weekend over the Appalachians and Mississippi River valley, but this is the exception to the rest of the region’s mostly marginal or unfavorable conditions for movement. And although portions of the Great Lakes and New England will experience light to moderate movements at times over the course of the forecast period, unfavorable southerly flow and precipitation is much more widespread and will mute movements in many areas. Species on the move this week will include Canada Warbler, Common Nighthawk, Baltimore Oriole, Black-and-white Warbler, Chestnut-sided Warbler, Black-bellied Plover, Blue-winged Teal, Blue-winged Warbler, Blackburnian Warbler, Least Flycatcher, Wilson’s Warbler, Bobolink, Olive-sided Flycatcher, and American Redstart.

Gulf Coast and Southeast

Warm and moist air dominates the region for the forecast period, with only a small area of marginal and favorable conditions to kick off the week and then again late in the week in the southern Appalachians, Mississippi River valley, and nearby Gulf Coast. Most movements will be light to locally moderate where and when they occur. Species on the move this week will include Olive-sided Flycatcher, Yellow Warbler, Alder Flycatcher, Yellow-bellied Flycatcher, Least Flycatcher, Blue-winged Teal, Black-bellied Plover, Northern Waterthrush, and Upland Sandpiper.