Forecast and Analysis

Regional Migration Forecast: 19-25 October 2013

Andrew Farnsworth The Cornell Lab Oct 18, 2013

Continental Summary:

Extensive moderate to heavy movements occur over many portions of the East during this period, representing a serious change of guard from the last later season Neotropical migrants and the growing waves of intracontinental migrants, while the West experiences a primarily dry week with widespread light and moderate movements. Birds on the move this week include Lesser Scaup, Bufflehead, Hooded Merganser, Common Loon, Horned Grebe, American Tree Sparrow, and Dark-eyed Junco.


Widespread light to moderate movements will continue this forecast period in most areas, although moderate movements will continue to occur primarily West of the Rockies along the Pacific Coast. Some northern and eastern areas may experience heavier movements from the beginning of the forecast period through the beginning of the work week, as conditions are favorable for migration to occur in eastern Montana and along the eastern front of the Rockies during those nights. This pattern may reappear late in the forecast period, as well, with favorable conditions forecast in eastern Montana and for portions of the eastern front for Thursday and Friday nights. Birds on the move this week include Cackling Goose, Northern Shoveler, Bufflehead, Lesser Scaup, Canvasback, Redhead, Hooded Merganser, Common Loon, Northern Harrier, Dunlin, Bonaparte’s Gull, Ruby-crowned Kinglet, Yellow Warbler, Dark-eyed Junco, and Pine Siskin.

Great Plains

Favorable conditions for migration will bring moderate to heavy flights to the northern and central Plains to begin the weekend. A passing low on Sunday reinvigorates the moderate to heavy flights in the northern Plains, although much of the remainder of the region will be quiet. Monday night will see most of the region under the influence of favorable migration conditions, and moderate to heavy movements will be widespread. These conditions shift East for Tuesday and Wednesday nights, with eastern portions of the Plains experiencing primarily light to moderate and some locally heavy movements. After a brief period of marginal and unfavorable conditions on Thursday, another round of moderate to heavy flights returns no Friday night for the eastern and central Plains. Birds on the move this week include Gadwall, Canvasback, Hooded Merganser, Ruddy Duck, Common Loon, Northern Harrier, Bald Eagle, Sandhill Crane, Bonaparte’s Gull, Northern Shrike, Horned Lark, Western Meadowlark, American Tree and Harris’s Sparrows, Dark-eyed Junco, and Purple Finch.

Upper Midwest and Northeast

Moderate movements are the norm from the Mississippi River valley East through DelMarVa and the greater New York metropolitan area and scattered North into south and central New England to begin the weekend. Portions of the Great Lakes and much of northern New England will experience little movement in precipitation. Conditions change rather drastically during the next two nights, when some areas will see migration shut downs in precipitation and southerly winds and others moderate to heavy flights in poor visibility and even light rain on Saturday night, and some areas East of the Appalachians experience moderate to locally heavy flight in clearing skies on Sunday night. Approaching low pressure resets the scene on Monday, and by Tuesday night another round of moderate to heavy flights is on tap West of the Ohio River valley. Note that some areas experiencing these movements may have poor visibility conditions and light precipitation, suggesting the potential for waterbird and landbird fallouts. Birders in the Great Lakes should be particularly mindful of this scenario. Wednesday and Thursday nights brings widespread moderate to heavy flights in favorable conditions across much of the region where precipitation is not falling. The end of the period sees these extensive movements relegated to only the northern reaches of the Upper Mississippi River valley and portions of New England. Birds on the move this week include Brant, Ring-necked Duck, Lesser Scaup, Bufflehead, Common Goldeneye, Black and White-winged Scoters, Hooded Merganser, Common Loon, Horned Grebe, American Tree Sparrow, Dark-eyed Junco, and Snow Bunting.

Gulf Coast and Southeast

Mostly unfavorable or at best marginal conditions keep movements light to moderate and widely scattered to begin the forecast period. This changes quickly, as a frontal boundary passing over the weekend spawns moderate to heavy flights in central Texas on Saturday night and over the southeastern Coastal Plain by Sunday night. A similar pattern unfolds early in the week, with another frontal passage spawning widespread moderate to heavy flights across much of the region away from the southeastern Coastal Plain, expanding over almost the entire region by Wednesday night. Thursday night sees continued moderate to heavy flights East of the Mississippi as high pressure builds into Central Mississippi River valley. Note, birders in Florida should watch for fallout potential, particularly in the Keys, on Thursday and Friday.Birds on the move this week include Gadwall, Ring-necked Duck, Ruddy Duck, Yellow-bellied Sapsucker, Hermit Thrush, Winter Wren, Ruby-crowned and Golden-crowned Kinglets, Orange-crowned and Yellow-rumped Warblers, Eastern Meadowlark, Savannah, Field, Chipping, Vesper, Song, Swamp, White-throated, and White-crowned Sparrows, and Dark-eyed Junco.