Thank you very much for both of you, and I'm sorry to hear about your situation, Brad. Hopefully, things will get better for you.
Just to clarify, I'm aware of the possible treatments and received professional advice in the past. The one thing though that I didn't get an answer for so far, or didn't find any information online, is the weather factor that I mentioned. It may be swelling as SassyLassie assumed.
You could have a problem similar to what I have - at your C6-C7 area, only I have it all the way down, starting at C1. Anyway, there are openings between the vertebrae through which nerves pass through. Sometimes, the vertebrae compress and put pressure on the nerve endings as they pass through those opening. This can cause pain in the wrist/arm/shoulder - wherever those nerves go. Because I have narrowed openings starting at C-1, not only have pain in my arms and shoulders, but also in my neck.
You might want to see a neurologist and discuss trying physical therapy to see if they can help enlarge the spinal openings to relieve the pressure from the nerve endings. I had about 12 weeks of PT (3 times/week) and between the exercises, massage and electrical stimulation, it helped considerably. I don't have equipment, at home, to do all the exercises, but I do the ones I can and it relieves the pain.
As SassyLassie suggested, a chiropractor might be able to help as well. I saw a chiropractor for a while, then opted for PT. I'm very glad I did it.
Like SassyLassie, I have no idea why it would be worse in hot weather - mine is equally bad year round.
Hi, I would suggest seeing a good chiropractor, if the issues start in the neck, he/she will be able to help as you may have some misplaced vertebrae pressing on the cervical nerves. If there are no chiropractors in your area, then try an Osteopath or naturopath. Acupuncture might help as well but it won't move the vertebrae.
As to why it hurts in heat, I am thinking that it is due to swelling, heat can make things swell, so it is probably causing the nerves to be pinched even more.