Without the knowledge of the strain, the grow, or pictures - Nobody can give you anything close to an educated answer. We don't even know what stage of the grow your in. For instance, if your in the first month of veg, this could be a temp issue, however, if we're in the 3rd week of flower, it could be strain genetics. There are so many variables here that the question actually needs guidelines:

What is your knowledge of the strain
What is your grow setup (not just CFL)
What are your high/low temps
Whats your RH?
What's your average PH?
Whats your grow medium?
What nutes are you using?
Where are you in the grow? Ie: Seedling, veg, flower - and how far along?
Pics will be helpful
Light leak info will also be helpful, as well as ventilation and fan use

Keep in mind - you asking this question is the exact same as me asking - Why does my car smell like gas? with no followup or leadin, there could be several reasons why someones car smells like gas - The last thing anyone would have guessed would be that someone walked through a puddle of gas before getting into the car.

We need the other information before an educated answer can be given.