As a tennis player, I often need to know when sunset will be (since the outdoor courts where I play don't have lights). Conveniently, Siri can tell me the time of sunrise and sunset. You cannot only find the time for today but also for any day of the next week. (Note, however, that Siri won't give you information for dates in the past.)
To ask Siri for the time of sunrise, simply say, "What time will sunrise be tomorrow?"
Siri will not only tell you the time, but will also give you a weekly forecast.
Or you can ask, "What time will sunrise be next Tuesday?"
Apparently you can only ask for a week into the future. I found that if I asked for the time of sunrise for a date weeks or months in the future, Siri would always tell me 5:48 a.m.
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