The most common causes of joint pain before it rains are rheumatoid arthritis, rheumatoid arthritis and osteoarthritis. 1. Rheumatoid arthritis: it is an autoimmune disease, usually refers to the immune system on the normal joint tissues of the wrong attack, which in turn induces joint pain, stiffness, and impaired mobility, and infections, genetics and other factors related to the rain before the weather becomes cooler may trigger inflammation attacks. 2. Rheumatoid arthritis: The causative agent of rheumatoid arthritis is group A beta-hemolytic streptococcus, which is typically manifested as wandering joint pain, and it is easily triggered in cold and wet weather, resulting in joint pain. 3. Osteoarthritis: due to the destruction of joint cartilage cells caused by various factors, resulting in degenerative changes in the joints, the weather before the rain is wet and cold, also easily caused by osteoarthritis attacks, swelling, redness and pain in the joints. Causes of joint pain before the rain is more reasons, may also be related to trauma, fasciitis and other factors, if the symptoms continue without relief, it is recommended to go to the hospital in time to identify the cause of the disease, the doctor targeted treatment.