How to predict a good sunset/sunrise
As a landscape photographer you might be familiar with this one problem. You take your car or your bike to drive to a certain location for shooting the sunset/sunrise. But when you are on a location and found some great compositions the sunrise/sunset is just boring. No glow, no clouds, nothing, or just a thick dense layer of grey clouds at the horizon. Not the most photo genetic scene.
First of all. It is very hard to predict a great sunset/sundown. But you can indicate whether its goint to be a good or a bad one.
Time of sunset/sunrise
The basic is that you know what time the sun is going to set or rise and with which azimuth. Google will help you finding it easily. Personally I use this website http://hemel.waarnemen.com/applets/oponder.cgi
It only works in the Netherlands and Belgium, but I am sure there are also sites for a lot other countries (http://www.sunrisesunset.com/custom_srss_calendar.asp). It not only gives the times and azimuths, but also