Exposure to the sun when outside. Cool the skin by sponging it with cold water or by having a cold bath or shower. Drink plenty of fluids to cool you down and prevent dehydration. Blistering or swelling of the skin (edema) chills. A high temperature (fever) of 38C (100.4F) or above, or 37.5C (99.5F) or above in children under five. Dizziness, headaches, and feeling sick (symptoms of heat exhaustion). Actinic (solar) keratoses-rough and scaly pre-cancerous spots on the skin. Eye problems such as photokeratitis (snow blindness) and cataracts.