10 weeks, White widow auto. Outdoor grow in 5+ gallon pot. Buds look good. Leaves turning yellow. Temperatures in the 90’s lately. 10-12 hours of sun daily. Could the heat cause the yellowing?
Welcome to the community! Do you have pics? Yellowing of older leaves is normal especially in later flower. If it’s just a couple/few at the bottom, they have most likely served their purpose and are dying off. Pics will help a lot. Good luck and happy growing!!!
looks healthy. just needs food i think.
Agree with @Spiney_norman whats your feeding routine and nutrients 
ILGM nutrients as specified.
Are you checking pH of the solution before watering?