I am having fluctuating temperature orally throughout the day , which is lower to about 98.2 in the morning,99/ 99.2/99.4 in the afternoon and evening, and again 98.2 at night on humid day, I get temperature of 98.4/98.6 in the afternoon and evening on the days when it rains outside and temperature is cooler inside the room. I have done full body checkup at a most reputated  hospital and nothing was found, Is it normal to have this variation??