Blackpoll Warbler. Don Martin/Macaulay Library. eBird S36477674.

Continental Summary

Favorable migration conditions early in the period bring light moderate flights to many areas of the West away from the Pacific Coast that will feature Dusky Flycatcher, Cedar Waxwing, Yellow-breasted Chat, Bullock’s Oriole, Chipping Sparrow, while the East will see locally moderate to very heavy flights featuring Short-billed Dowitcher, Black Tern, Red-headed Woodpecker, Olive-sided Flycatcher, Eastern Kingbird, Swainson’s Thrush, Canada Warbler, Common Yellowthroat, and Orchard Oriole in mostly marginal migration conditions that in many areas will hinder or inhibit migration. The second half of the period will see the best chance for more trans-Gulf migration as well as another opportunity for fallouts and concentrations with a passing frontal boundary.

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.

We use data collected by eBird users help make more accurate forecasts. If you enjoy the predictions contained in these posts, please consider submitting your own bird sightings to eBird to even further improve the content. Every observation counts, whether it be a single bird at a feeder in your backyard, or an entire day spent in a national park. To get started with eBird, head on over to the site!

Please note that photographs and other digital media showing birds come from the Macaulay Library, which receives credit along with the photographer/observer in the media caption as part of a new initiative that allows public contribution, access and use of natural history media.

Finally, and new for Spring 2017, our friend Kyle Horton of the Radar Aeroecology Lab at Oklahoma University created a new set of images depicting spring bird movements in the Gulf of Mexico region as part of an analysis that he is leading as part of our ongoing collaboration. This feature appears in the Gulf Coast and Southeast region forecast.

Need a review of our definitions for regions, species on the move, and migration amounts? Please visit this link.

Quick Links to Regions

Upper Midwest and Northeast	Gulf Coast and Southeast
Great Plains	West

Upper Midwest and Northeast

The first half of the period will see localized pockets of marginal to favorable migration conditions mostly along the immediate coast and New England, where light to locally heavy movements will occur. Those with an interest in flight calls should consider listening during these periods if movements are occurring, as low visibility in conjunction with artificial lighting can inspire significant calling activity. The extent and intensity of these early period movements will be determined largely by the extent of precipitation and speed of unfavorable winds aloft. Birders in these areas should also be watchful for some migrant overshoots, birds entrained in the passing low pressure system (see our brief discussion here). The latter half of the period will see even more restricted movements, as generally unfavorable conditions build into the region, including opposing winds and unseasonably cool temperatures. Note, however, that subtle changes in these factors, especially calmer than expected wind conditions, can allow significantly higher intensity movements to occur.

Birders in New England and the Canadian Maritimes should watch carefully as atmospheric circulation across the North Atlantic is forecast to begin to change markedly, with more easterly flow forecast in the coming week. This could lead to the arrival of European Golden-Plover, Black-tailed Godwit, and other European vagrants in these areas.

Dunlin. Dennis Swaby/Macaulay Library. eBird S36525002.

Species on the Move

Beginning Arrivals What is this?

Peaking Arrivals

Beginning Departures

Ending Departures

Gulf Coast and Southeast

With a strong frontal boundary departing the region to kick off the weekend, most of the region east of the Mississippi River will experience a relative dearth of birds for the first half of the period. Light to locally moderate movements will be the norm, although heavier than expected flights may occur in calmer conditions, particularly in Florida and the southeast. To the west of the Mississippi River, conditions are more favorable, with moderate to heavy flights likely, increasingly so, through the first half of the period. By Wednesday the entire region begins to experience more favorable conditions, with moderate to heavy flights widespread in the region and trans-Gulf movements in full swing. The period ends with another frontal passage with potential to produce more fallouts and concentrations, particularly in the eastern Gulf region.

Canada Warbler. Dan Vickers/Macaulay Library. eBird S36415926.

Beginning Arrivals What is this?

Peaking Arrivals

Beginning Departures

Ending Departures

Weekly mean spring nocturnal migration activity and direction of movement in the Gulf of Mexico region for the week of 4-10 May, 1995 to 2015. Circular buffers around radar stations represent migration activity scaled to radar reflectivity (a measure of biological activity), with weekly activity represented by size scaled to the activity at KCRP Corpus Christi and seasonal activity represented by colors scaled to the most intense movements of the spring period (L: light, M: moderate, H:heavy); arrows represent mean track direction (a measure of the direction birds are traveling) derived from radial velocity.

Great Plains

After a slow start to the weekend, moderate to locally very heavy flights are likely for the days that follow. By Tuesday night, as a disturbance moves into the central Plains, more southerly areas will continue to experience good migration conditions whereas more northerly areas will start to experience much less favorable conditions. These less favorable conditions become more widespread to end the period, with migration diminishing in intensity and extent; movements will be mostly light to locally moderate. Note that some more westerly areas of the Plains may see higher than expected intensities, particularly in the central and northern areas.

Bell’s Vireo. Petra Hockey/Macaulay Library. eBird S36470828.

Species on the Move

Beginning Arrivals What is this?

Peaking Arrivals

Beginning Departures

Ending Departures

West

The weekend will bring moderate flights in many areas, though mostly east of Pacific Coast and coastal ranges. Some of these flights, particularly east of the Rockies and in portions of the Desert Southwest, may be heavy. As the work week begins, these favorable migration conditions will become increasingly restricted to the southern Rockies and Desert Southwest, with similarly intense movements continuing. However, by Wednesday favorable migration conditions appear in almost an opposite pattern, with portions of the Pacific Coast and northern Rockies seeing light to moderate flights in contrast to a much quieter Desert Southwest. To end the week, a pattern between these extremes emerges and scattered light to moderate flights are likely in a number of areas; but most of the activity will be east of the Continental Divide.

Chipping Sparrow. Tim Ryan/Macaulay Library. eBird S36484098.

Species on the Move

Beginning Arrivals What is this?

Peaking Arrivals

Beginning Departures

Ending Departures

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Farnsworth and Van Doren