We don't get Texas style heat here in CT., but July/August are usually pretty miserable here. Temps in the mid 80's to high 90's and humid. Plus, the deerflies are out, so the dogs stay in for the most part. Those deerfly bites leaves patches of missing hair!
No forest romps during this period. Early morning swims is the norm.
Keep your poochies safe in the heat!!
My main concern with heat is blacktop pavement. Nobody has any business walking their dog on blacktop when temps get high and sun is out. Here in NC , I take Ellie for noon walks when its 95F out, the main thing is that it is in the woods where it is much more bearable for both of us. We're only exposed for a few minutes to get into the shade of the woods. No way would I be walking her in the direct sun exposed when the temps get that high unless if it was early morning or evening.