Heat cramps are painful muscle cramps and spasms, usually in the legs and abdomen. They may also be a symptom of heat exhaustion. Apply firm pressure on cramping muscles or gently massage to relieve spasms. Give sips of water unless the person complains of nausea, then stop giving water.

An extreme heat warning is in effect through 8 p.m. Wednesday. Heat Index values will be between 110 and 115 degrees. Isolated thunderstorms are possible Wednesday afternoon through the evening, mainly east of I-65.

An extreme heat warning and an extreme heat watch were issued by the National Weather Service in Jacksonville for July 28 and 29.