I am a new diver in the Puget Sound area and have only done cold water dives. How different does it feel diving in warm water? Do you notice changes in your air consumption from not having to expend as much energy keeping warm? I use a 7mm farmer john wetsuit and at the end of dive 2 I there is little better than a heated shower/drink.
Apologies if this has been asked recently, I poked around using the search function but didn’t see anything.
Air consumption will generally be less as you are more comfortable. Less exertion/frustration in fighting a thick wetsuit with hood and gloves. But, you will find that your air consumption will go down the more you dive cold water as your overall comfort in diving and skills improve.
A cold water diver comfortable in diving the cold with typical lower viz, who is then placed in warm and clear water, will be light years ahead of a warm water diver who is placed into cold water.
So get out there and dive your cold waters, your local quarries, mud holes, or whatever it is you have. Keep your skills fresh and sharp. As we said in the Army: train hard, fight easy.