The warmest months in Tampa are May through September, which can also be humid. There is also more rainfall during these months due to the humidity. If you do not mind the heat or the humidity, then these are great months to visit Tampa. The cooler months start in October and go through June.  We have visited during both the warm and cool seasons and found the cooler season more pleasant than the hot season. However, the hot season wasn’t so bad, and when it became hot, there was always a pool in which to cool off. I would say that any time is a great time to visit Tampa. The only thing I would keep in mind is that hurricane season in Florida begins in June and goes through the end of November.