Well, it's finally here. The long-awaited total solar eclipse will occur tomorrow afternoon across the United States. So what IS a solar eclipse? A solar eclipse occurs when the moon becomes positioned between the Earth and the Sun. Solar eclipses happen about twice each year, but viewing a total eclipse in the United States is somewhat rare. This will be the first total solar eclipse visible from anywhere on mainland United States since the total solar eclipse in March 1979. The next one will be in April 2024, but it will not be visible from nearly as many US locations as the 2017 eclipse (dates via timeanddate.com).
Tomorrow's eclipse is a TOTAL eclipse. The path of totality stems from Salem, Oregon to Casper, Wyoming to Kansas City, Missouri/Kansas to Nashville, Tennessee to Columbia, South Carolina. Below is a map of the path of totality, along with the time of passage, and duration that the eclipse will last at your location. For example, if you were located near Kansas City, you'd see totality near 1:10pm CDT, and it'll last for around 2 minutes and 40 seconds. The entire eclipse process, though, will last nearly 3 hours for most locations!
Image from GreatAmericanEclipse.com
Don't worry if you're outside of the path of totality- you'll still get a show from nearly every location in the United States! The yellow lines on the map show percent of totality that locations in North America will witness. For example, even if you are located in central Utah you'll see around 90% totality, and locations in central Pennsylvania will witness around 80% totality. Information for various locations' totality viewing is shown in the table below:
So, what do you expect to see? Throughout the 2.5-3 hour eclipse process, you'll see a gradual darkening of the skies, as if the sun were setting. At totality, the color of the sky will be a navy-blue, with a sunset-like strip of brightly colored (yellow/orange) sky around the entire 360-degree horizon. Near totality, viewers will be able to see a "sparkling" sensation appear near the edges of the moon, as sunlight is moving over the moon's crevasses. After totality, you'll see a gradual lightening of the sky, as if you were witnessing sunrise. If you are to look up at the sun during the eclipse, here is what you'll see:
Image from NASA
*Viewing the solar eclipse can be very dangerous to your eyes; you MUST wear solar eclipse glasses if you are not in the path of totality, or if you are in the direct path but the eclipse is not total. If you look at the eclipse without glasses when it is only partial, you blindness in one or both eyes may result.* Here's a look at the difference that solar eclipse glasses make when viewing the sun, compared to no glasses and polarized glasses:
Image from Meteorologist Lindsey Monroe
Now that you know what to look for and when, the only other thing that may put a damper on your experience will be the weather. Cloud cover probabilities are increasing for many places along the path of totality for tomorrow afternoon, especially in the north-central and southeastern portions of the United States, as well as the Four Corners region and into southern Nevada. Showers and thunderstorms are likely in the upper Midwest, near Iowa, Minnesota, southern Wisconsin, and northern Illinois near viewing time for those areas. Blue areas on the map below are likely to see clear skies tomorrow afternoon during the eclipse:
Image from the National Weather Service, valid for 2pm EDT
Solar eclipse fun fact: depending on your local sky conditions, places in the path of totality may see a temperature drop of near 20 degrees tomorrow afternoon!
Forecast updates with viewing conditions will be posted tomorrow morning at tdsweather.com and on our social media accounts. Tweet us your solar eclipse pictures and videos @tdswx, or share them with us on Facebook /tdswx. Happy viewing!