TeenHealthFX assumes you are talking about your body temperature. Your normal body temperature is considered to be 98.6°F. Throughout the day it can fluctuate within a narrow range that is considered normal. Depending on your activities and body it can vary from .5°F to 1°F.
Your temperature will naturally be lowest early in the morning and rises in the evening. After a night's rest your body has been physically inactive (however you are still performing vital processes), you have not done much moving and have been provided with external warmth (your blankets). Your temperature will accordingly be lower. In the evening you have gone through a full day of activities, which may include exercising. Exercising and normal movement will raise your temperature. (Think about all those active processes going on in your body.)
If you have a specific concern, you should see your doctor.