How to Use BirdCast Maps and Dashboard to See Your Local Migration in Detail

Updated April 2026. Originally published online April 2018 and printed in the Spring 2019 issue of Living Bird magazine. Subscribe now. Migration is the best time to be a birdwatcher.... Read more »

Pets & Animals Apr 28, 2026 0 4 Add to Reading List

How to Use BirdCast Maps and Dashboard to See Your Local Migration in Detail

Updated April 2026. Originally published online April 2018 and printed in the Spring 2019 issue of Living Bird magazine. Subscribe now.

Migration is the best time to be a birdwatcher. Twice a year, hordes of birds fly thousands of miles through the night to grace your home turf for a few days or weeks. But they don’t come in a steady stream. Even during peak migration, some days are quiet while others are packed with new arrivals.

Birders have for decades tried to guess which nights would be big ones for migration. That dream took a big step forward in 2018 with the launch of BirdCast and its 3-day migration forecasts for the Lower 48 states.

Since then the team, consisting of scientists from Cornell Lab of Ornithology; University of Massachusetts, Amherst; Purdue; and University of Illinois, Urbana-Champaign; has steadily built BirdCast’s features—all of which are free.

In essence, BirdCast boils down decades of migration science and couples it with real-time radar data to create a powerful suite of tools. Read on for our guide on how to get started:

Migration Forecasts. Get a 3-day estimate of how many birds will be on the move across the Lower 48 states each night.

Live Migration Maps. View current migration traffic, updated every 10 minutes through the night.

Migration Dashboard. See county- or state-level stats for total migration traffic, direction, and speed each night. A data archive lets you see stats from previous nights/years, too.

Expected Species. Find out which species are on the move in your area right now.

Local Migration Alerts. Sign up for emails to know when waves of migrants are on their way to you.

How to Use BirdCast’s Migration Tools

1. Check the 3-Day Forecast

BirdCast’s Migration Forecasts tell you how much migration is predicted to occur in the next few days, information that can be helpful for planning your next birding trip. Below the main map you’ll see thumbnails of predictions for the next three nights (click or tap to see full images). Casting your eye over these maps will give you an idea of how the next few nights are shaping up.

The magic of the forecast maps is that they compile more than 25 years of data on when migrants are on the move and mash it up with meteorological data including wind speed, direction, barometric pressure, and temperature. You no longer have to have a PhD in migration ecology to use all these variables: just look for the brightest colors on the maps to know when to go.

BirdCast creates 3-day forecasts of migration activity for the Lower 48. Brighter colors indicate more bird traffic. Gray areas show weather fronts that may disrupt migration.

2. See Local Migration Activity in Your County

Like all forecasts, a migration forecast is a prediction based on computer models—it’s not always right. To see data of what actually happened last night, use Live Maps for an overview and Migration Dashboard to get details.

The amazing thing about Migration Dashboard is that it can compute an estimate of migration traffic for every county in the Lower 48 states. Just enter your county or state in the main search bar to bring up your local results. Frankly, we think it’s mind-blowing to see just how many birds are in the air over a single county on any given night.

Migration Dashboard also tells you details about the birds’ average speed, direction, and altitude—and compares these stats to historical patterns, all on one screen.

Migration Dashboard uses live data from 143 radar stations, compiling about 100 gigabytes of data every night via an algorithm designed by the BirdCast team.

You can check migration stats during the night—they’re refreshed every 10 minutes—or look at them first thing in the morning to get an idea of where to go birdwatching. To see stats for previous nights, just select a different date at the top of the screen.

The Live Maps feature displays migration activity in near-real-time each night during spring and fall migration. You can watch live each night or review previous maps by day. In these animations, the red line shows sunset; yellow line represents sunrise.

Migration Dashboard shows you estimated migration traffic for any county or state in the Lower 48. This example shows more than 2 million birds passed over a single county in Tennessee in one night.

3. Know Which Birds to Look For

Radar is good at estimating numbers of birds, but it can’t identify species—one of the top questions a migration-obsessed birder might have.

But by tapping into the vast eBird database, Migration Dashboard can make an informed guess. Drawing on thousands of local eBird checklists, the tool compiles information on migration timing and presents a list of the bird species most likely to be arriving or departing your area on any given night.

After you’ve selected your county or state on Migration Dashboard, look for the Expected nocturnal migrants section below the top banner to get a sense of which birds to be on the lookout for.

The Migration Dashboard page features a section that lets you know which migrants are especially likely in your area on this date.

4. Sign Up for a Local Migration Alert

Want to get advance notice for when heavy nights of migration are approaching? Check Migration Alerts to find out whether high migration is expected for the next night.

You can even sign up to receive emails whenever migration is predicted to be high in your area—so you won’t miss out even if you haven’t checked the BirdCast website.

To sign up for a migration alert, choose your region, and then select the city nearest to you. Enter your email address, and then click on the confirmation email BirdCast will send you.

5. Help Make Birds Safer

BirdCast tools are a gift to birdwatchers looking to fine-tune their birding schedule—but the team has a bigger goal in mind.

By creating accurate forecasts and up-to-the-minute monitoring data, they hope to provide tools for managing wind turbines and city lights. Collisions with lighted windows (and, to a lesser extent, cell phone towers and wind turbines) are a major cause of bird death. But the majority of migrants come through on a few nights each year, meaning that a few fairly easy adjustments could save huge numbers of birds.

BirdCast provides a helpful map view of peak migration dates at the county level for the entire Lower 48. Hover over any county on the maps to view peak spring and peak fall migration dates—these are the times when it’s most beneficial to dim your outside lights.

The two key steps you can take to help birds are to turn out nonessential lighting and make your windows safer. Detailed recommendations can be found on the BirdCast Protect Birds page as well as at the Bird Collision Prevention Alliance.

About BirdCast Data

The BirdCast maps make the most of the available data and models, and have undergone significant testing. Still, bear these caveats in mind as you start to use the maps.

Coverage is limited to the U.S.—why? We agree, it would be great to extend these maps to Canada and Mexico, but the radar infrastructure and the real-time data connections don’t currently allow that.
Bird numbers are approximate. The real time migration maps estimate activity in thousands of birds per kilometer. These numbers are based on songbird-sized birds—it’s possible that there could be smaller numbers of larger birds creating the same signal.
Radar can’t tell bird species. Radar data can tell us a lot, but at the moment it can’t tell us which species are migrating. Migration Dashboard uses radar data to tell when birds are moving, and eBird data to give a best guess of which species are in the air.
Watch for storms. Birds typically migrate during clear weather and drop to the ground when it starts raining. This means weather fronts can greatly alter migration activity at a local level. The 3-day forecast maps alert you to this by showing major weather systems in gray and black on the maps. Migrants may “fall out” en masse on the near side of a weather system, and be scarce on the far side the next morning.
Migration activity varies across the continent. BirdCast maps show migration activity on a purple-orange-yellow scale. High-migration areas such as the Gulf Coast and the Mississippi Flyway will reliably turn yellow (or even white) during peak migration. Other parts of the country, such as the Rockies, will rarely show yellow, even on locally good nights, because they don’t reach the same level of activity. Even so, BirdCast migration alerts take this national variation into account and highlight high migration activity that is relevant for your specific area.