I was in a pickle recently. My daily run was scheduled for 7:00 pm with some local runners. Unfortunately, I was unable to make it back into town on time and I was forced to make a decision. The time was well past 10:00 pm and it was as dark out as it was going to get. I decided to go ahead and run six miles. I made sure that I ran along well traveled and well lit (major necessity) streets and it really amazed me.
There are many advantages to running at night; and, as I found out, there are big disadvantages as well. The biggest advantage definitely would be temperature. I ran from 10:30 to 11:10 pm and the temperature at the time ranged between 67-73 degrees Farenheit. At high noon that temperature was in the high 80's and 90's. So the temperature difference is about 20 degrees and that is vital. With a night run you are less likely to get dehydrated or overheated where during the day you may be at high risk to develop these problems. Another major advantage is traffic. Late at night most people have settled in at home and the traffic on the streets isn't too bad at all.
The biggest disadvantages that I encountered would have to be the footing. In some areas the sidewalks aren't too well lit; you're running smoothly along, then watch out! The sidewalk ends and, with a dip, the driveway begins. You could be running along fine one stride and then you stick the other leg out and drop six inches without any warning. This can be dangerous. With the advantages and the disadvantages all taken into account I would say that a night run is better than a day run as long as you feel safe with it.
Tip submitted by Derek Leininger.