Expert: Courtney Seligman - 7/24/2010

Question
Seeing a total solar eclipse is in the top ten of my "bucket list," a list of things I'd love to do before I die.
If I can make it until the 2017 eclipse in the US, I need some good information. Where would we see the longest duration of totality? My brother is going to Wyoming on the advice of a professional astronomer, his wife's brother, but doesn't know why. Many of my friends want to go to Kentucky. Again, I don't know why. As I live near Dallas, the drive to Kentucky would be shorter, but I've never seen Wyoming, and it might be a tad cooler in Wyoming. Is there any way of getting a _rough_ idea of the odds of rainy weather for August in those areas along the path of totality? Any advice you could give me would be _tremendously_ appreciated.

Answer
I presume that astronomy magazines (physical and online) will be full of weather predictions in the year prior to the eclipse. Other than that, all I can suggest is to check the average weather in different areas along the eclipse path at weather.com, or some such site.

To see where the total eclipse will be visible, check out http://eclipse.gsfc.nasa.gov/SEplot/SEplot2001/SE2017Aug21T.GIF , which is a map produced by NASA scientist Fred Espenak (one of the best places to enter "his" site is http://eclipse.gsfc.nasa.gov/solar.html , as it gives very thorough tables of eclipse pages and data available on the site).

As the plot shows, the "greatest" eclipse, which is a little over 2 1/2 minutes, will be visible (weather permitting) in southeastern Illinois; but I'd guess that the duration of totality will be within half a minute of that all the way to the Carolina coast to the east, and into the Dakotas on the west. As you move closer to the northwest coast of the country the length of totality should gradually reduce, and my guess would be that weather might be more variable.

I expect that the recommendations your friends and relatives received were probably based on guesses about the weather which were as variable as who they talked to; and even the best guesses can fail if a single cloud covers the Sun at the crucial time, or the worst ones succeed, if a hole opens in an otherwise cloudy sky. However, I wouldn't worry about picking any specific location just yet. As the time approaches, read what you can, and perhaps look for a place with good roads which more or less parallel the eclipse path, so that if the weather looks foreboding where you are, you can try another spot, a little east or west of your original location.

Finally, although the fact that the 2017 eclipse passes through the United States makes it more convenient to get to, there are total eclipses somewhere almost every year, and eclipse cruises or tours which should allow you to see an eclipse well before then, if you have the time and money to do so.