What organization, founded in 1848, began by attacking "lay" doctors and institutionalized its authority through standardized programs of education and licensing?

The American Medical Association begin attacking "lay" doctors and institutionalized their authority through standardized programs of education and licensing.
Nathan Smith Davis Sr., M.D., LLD was a physician who was instrumental in the establishment of the American Medical Association and was twice elected its president. He became the first editor of the Journal of the American Medical Association.

Mild is the answer

This is caused by hot summers and cold winters