Winter is not necessarily a season of the year that we associate with bird migration. This is for good reason, as the epic movements of spring and fall are not usually underway and nowhere do we find the diversity in northern hemisphere temperate latitudes of migrants passing that we expect and experience during those seasons. […]  Read more...

This is the final forecast and analysis report for the Fall 2013 season. Please continue to visit BirdCast.info for updates and commentary on noteworthy movements of birds during the coming months, and look for weekly forecasts to resume on 1 March 2014. Continental Summary: Diminishing returns aside (no pun intended), the West saw local light […]  Read more...

Continental Summary: Scattered light movements will occur in portions of the West, as the East sees a substantial movement to begin and end the period. Birds on the move this week will include Bufflehead, Common Goldeneye, Hooded Merganser, Ruby-crowned Kinglet, Gray Catbird, Yellow-rumped Warbler, and American Tree Sparrow. West As we near the end of […]  Read more...

Continental Summary: Scattered light movements were the norm in the West, with only a few areas of more intense movements, as the East experienced some substantially heavier migration than expected, particularly along the East Coast. Birds on the move this week included Gadwall, Bufflehead, Hooded Merganser, Gray Catbird, Common Yellowthroat, Indigo Bunting, and Dark-eyed Junco. […]  Read more...

Continental Summary: Light to moderate movements are the norm across the country this week as species diversity and numbers pass peak in many areas, although some locally heavy movements begin the period in the Southeast. Birds on the move this week include Bufflehead, Hooded and Red-breasted Mergansers, Ruddy Duck, Common Loon, Horned Grebe, Bonaparte’s Gull, […]  Read more...

Continental Summary: The West experienced one of the last of the extensive light to moderate movements of the fall along the Pacific Coast and in the Desert Southwest, as the East experienced some widespread pulses of moderate movements and a few locally heavy movements in the Southeast. Birds on the move this week included Gadwall, […]  Read more...

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 […]  Read more...

Continental Summary: Two pulses of movements rushed through the East, as continuing light to moderate movements were steady in the West. Birds on the move this week included Hermit Thrush, Ruby-crowned and Golden-crowned Kinglets, Yellow-rumped Warbler, White-throated Sparrows, and Dark-eyed Junco. West Most of the region experienced light to moderate movements to begin the weekend, […]  Read more...

Continental Summary: Widespread light and moderate movements across the West are still apparent, as a major pulse of northerly flow brings a large flight to the East by midweek. Birds on the move this week will include Northern Harrier, Chimney and Vaux’s Swifts, Orange-crowned Warbler, Eastern and Western Meadowlarks, Song, White-crowned, and White-throated Sparrows, and […]  Read more...

Continental Summary: Pulses of light to moderate movements continued in the West, as a large movement in the East saw large numbers of birds moving across the region and transiting through and to the Southeast. Birds on the move this week included Canada Goose, Hermit Thrush, Golden-crowned and Ruby-crowned Kinglets, Yellow-rumped and Palm Warblers, Song, […]  Read more...

Continental Summary: Both West and East experience periods of moderate to locally heavy movements this week, as the large but increasingly less diverse movements of October are in full swing. Birds on the move this week will include Golden-crowned and Ruby-crowned Kinglets, Hermit Thrush, Yellow-rumped Warbler, White-throated Sparrow, and Dark-eyed Junco. A brief note about […]  Read more...

Continental Summary: Widespread light and moderate movements occurred across the West during the period, including some coastal flights allied with Santa Ana winds in southern California, while two strong pulses of moderate movements occurred during the middle of the period in the East. Birds on the move this week included Yellow-bellied Sapsucker, Hermit Thrush, Golden-crowned […]  Read more...

A strong low pressure system is forecast to move across northeastern Asia and the northern Bering Sea late on Thursday 3 October and early on Friday 4 October. Forecasts call for strong westerly winds with this system, which is quite large, across a broad area of the Bering Sea and Alaska. Given the size of […]  Read more...

Continental Summary: The West continues to show a patchwork of locally moderate movements in airspace free of precipitation, and the East gets another pulse of moderate to heavy flights, including in the Southeast and Florida, followed by another strong high pressure center continuing the flights in New England and its immediate vicinity. Birds on the […]  Read more...

Continental Summary: Changeable conditions across the West spawned scattered and sometimes moderate movements in a patchwork across the region, as strong high pressure dominated the eastern US and spawned extensive and continuing moderate to heavy movements. Birds on the move this week included Eastern Phoebe, Blue-headed and Warbling Vireos, Ruby-crowned and Golden-crowned Kinglets, Wilson’s, Palm […]  Read more...

In the wake of much discussion about atmospheric blocking in Fall 2012, Team BirdCast returns to the scene of the crime, so to speak. The Climate Prediction Center, among others, is forecasting a period of negative North Atlantic Oscillation (NAO) indices in the coming weeks. These negative values correspond to building high pressure over Greenland […]  Read more...

Birders along the Pacific Coast of the US, along with The Weather Channel and the Los Angeles Times, have certainly noticed the recent invasion of Blue-footed Boobies in California, whether you’ve read about it on eBird or seen it in person. Similar large-scale movements are occurring for other species along the Pacific Coast (for example, […]  Read more...

Continental Summary: A pulse of moderate movements occurs midweek in the West, as the East experiences a major frontal passage followed by a building high pressure ridge that facilitate major movements over land and over water. Birds on the move this week will include Yellow-bellied and Red-naped Sapsuckers, Golden-crowned and Ruby-crowned Kinglets, Yellow-rumped Warbler, Swamp, […]  Read more...

Continental Summary As the East pulsed with a major frontal passage and moderate to heavy movements in its wake, the West continued previous weeks’ pattern of many moderate movements. Birds on the move this week included Broad-winged Hawk, Northern Flicker, Warbling Vireo, Northern Parula, Palm Warbler,  Common Yellowthroat, and Lincoln’s Sparrow. West Moderate movements in […]  Read more...

Team BirdCast continues to try to provide some insights on the comings and goings of vagrants in the Bering Sea! The coming days have some great potential for Asian strays to appear in the Alaskan island chains, particularly given pervasive high pressure over the central eastern Pacific that is driving low pressure systems toward and […]  Read more...