I looked for my dates mid/late Aug out of curiosity (I already booked for $205 RT out of DC) and the lowest I could find on a Tues or Wed was $120 one way. It actually made me feel better I didn't wait because I knew a sale would come up.
The lowest I ever got was about 8yrs ago. $39 one way on SW out of BWI. Those were the days.
One thing I found with Jet Blue is to go half way thru booking to pick seats. If a lot are already taken, take the best deal. If there is a lot of availability there is a good chance those flights will be discounted 1-3 months out.