Curling shingles are often caused by excessive heat and moisture buildup, typical in humid climates with high temperatures. This condition can also arise from poor attic ventilation, allowing heat to accumulate under the roofing material. Homeowners can spot this issue early by regularly inspecting the roof for shingles that have corners turned up or centers that appear concave. It's important to check these signs from the ground using binoculars or by viewing higher sections from a safe vantage point, avoiding walking on the roof to prevent further damage.