It's to do with the hypothalamus. 
What Causes Temperature Sensitivity 
Body temperature is regulated by the hypothalamus. The hypothalamus is a section of the brain responsible for hormone production. It is considered the link between the nervous system and the endocrine system.

The hypothalamus not only controls body temperature. It controls energy levels, the sleep cycle, muscular function, circulation, the gut and defense against infection.

Most fibromyalgia symptoms seem to be due to imbalances in the hypothalamus-pituitary-adrenal axis (HPA axis). These three glands work together to control hormone levels. Disruptions in the HPA axis seem to be at the core of fibromyalgia.

Thyroid hormones also play a role in regulating body temperature. An overactive thyroid (hyperthyroidism) can cause a person to feel too hot, while an underactive thyroid (hypothyroidism) can cause a person to feel too cold.

The thyroid gland is under the control of the pituitary gland. The pituitary gland itself is regulated by the hypothalamus. Anything that disrupts the HPA axis will also suppress thyroid function.

I live in ohio. I seem to be better in the warmer weather. I'm in a lot of pain most of the winter. Winter here lasts too long.

Yes I lived in Phx and I couldn't stand the extreme heat .
I moved yo OR and use electric blankets and heating pads.
Extreme Temps don't do any favors for fibro ppl.

Absolutely! This humidity is killing me.

Oh yes definitely 🥵😰🙌