As a photographer, especially a landscape photographer, you’re often on the lookout for a great sunset or sunrise. That magnificent golden sky! But those magical skies don’t happen too often. So how can you make solid predictions. Well actually you can’t. At least none that are 100 percent accurate. But there are some factors that enlarge the chance of a beautiful colored sky.
Logically those magical skies only happen at golden hour. The time just before and after sunset or sunrise. Those are the times the sky can really look like gold.
What’s most important to determine how great chances are for a beautiful sunset or sunrise is the layout of the cloud cover. Cloud cover can be divided into three categories.
1) Low clouds (below 8,500 ft)
2) Middle clouds (8,500 ft – 20,000 ft)
3) High clouds (above 20000 feet)
For a golden colored sky you’ll need clouds, so a clear sky will give you a great look at the setting sun, for sure, but it wont give you any golden color in the sky. You need clouds for that, especially the ones that we refer to as high clouds. Those are the clouds that best reflect the last visible light from the sun. They are way up high in the sky leaving enough room for the last (red) light from the sun to reflect on the clouds and reach our eyes and camera sensors. All clouds that we refer to as middle clouds are often too low in the sky to reflect light in the right way and reach us. And with a fully covered sky of low clouds your chances of a great colored sky at sunset are nearly zero because those kinds of clouds will only block any visible light from the sun. So cloud coverage is important, but how do we know how the layout of the clouds will be at golden hour?
fun little fact
For those of you who might ask why often only the red, orange and yellow light reaches us at sunset or sunrise? Well, within the visible range of light, red light waves are scattered the least by atmospheric gas molecules, at sunset and sunrise the light has to travel a longer distance through the atmosphere (and atmospheric gasses) to reach us, so mostly red, orange and yellow light will reach us.
Fortunately the internet provides us with all sorts of information. So I searched for a suitable way the determine the layout of the clouds at golden hour. I found two websites that provide us with such information.
http://www.windguru.cz/
http://www.skippysky.com.au/
Windguru
This website provides you with information mainly on wind and wind speed. It’s aimed at those who rely on wind for sailing and water sports. But the website also provides in depth information on the layers of clouds. In the example below you’ll see that information for my region (the North of the Netherlands). The cloud cover is decided in those three height categories. This let’s you determine how great chances are for a great colored sky at golden hour. You want the percentages for the high clouds to be higher and the middle clouds lower and the low clouds preferably at zero or close to zero.
Skippysky
This website is aimed at people who like to observe the night sky and look at the stars. This comes in handy because people who like to look at the night sky need a clear sky, so as few clouds as possible. The website gives a graphical indication on how those three types of clouds are positioned on the map and how dense those layers are. Below you’ll see three images: the first shows you how dense the low clouds will be. You’ll be wanting to see blue on this map because you don’t want any low clouds. The second image shows you the density of the middle clouds. You’ll mainly want it to turn blue also. Some clouds in this layer is not a big problem but once it goes beyond 40% your chances of a great sky are getting worse. And lastly you’ll find an image of the high clouds. Here you’ll want to see clouds. So anything between 30% and 90% will work great for a perfect golden hour sky!
I put up 21 images. The first three show you the predicted cloud situation in about six hours time. The second row of images is nine hours ahead and so on! In this way you can also spot the movement of the clouds and base your conclusions on that. Over time you’ll find that you’ll be better at predicting those golden skies. But remember, there’s never a guarantee on success! 🙂