DrJynx86answered grow question 4 years ago 81 F is cold for cannabis, lol.
As long as you don't get into the 90-95+ you're Ok, even then, if you have good ventilation and can keep up with the used CO2, then plants can sustain up to the 95+ for sure, but only with good ventilation and CO2 injections.
Your temps are normal for spring, not even summer, do not worry and keep on the great care!
Happy smokes!