blowtorch
Registered
Blowtorch:
And Pennyroyal Blue Springs Resort is the local quarry near me. Quarries can be very deep, which coupled with their overall size and structure, can lend itself to forming thermoclines. At Pennyroyal even over in August, the surface water may be warm but down around 15 feet it abruptly shifts to cooler water, where I'd want to wear a full wetsuit. Get on down deeper, and there's another thermocline; hang out at 80 - 90 feet deep and you're looking at roughly mid-40's degree F water.
Freshwater won't give you precise answers about weighting and trim needs for ocean diving, but a deep, cold quarry can give you a sense of how well your exposure protection works, and offers an inland training site.
I use conversion Fahrenheit to Celcius. It said -40 is also -40 in Celcius. Is that correct? 40F is 4.4C. That is already cold. The coldest I have experienced is 15C few years ago. The cold add extra pressure to the chest but still was a good day.