The soil is damp around the tomato plant but not so wet that it should cause your tomatoes to split.
Some reasons tomatoes will split:
Allowing your tomatoes to dry out and then giving them too much water.
Too much water during high heat conditions.
Weather conditions that cause the fruit to increase in size faster than the skin can stretch.
Genetics can be a factor in splitting tomatoes.
It is best to deep water tomatoes on a regular basis. Balance the water they receive. Don’t allow them to dry out but don’t over water either.