When you use the word, APPARENT, it shows more confidence and assurance.
You would use this word when there was more evidence that things were true.
For example, you might say, the motion of the earth around the sun is apparent because there is a lot of evidence.
You would use the word SEEMINGLY when there was less evidence.
For example, you might say, his intentions were seemingly honest because there is some proof.
For things you are even less sure of you might you the word, PROBABLY.
For example, you could say, the probable cause of a fire was arson because the evidence is unclear.
Hope this helps.