A Raynaud's attack is a condition where small blood vessels in the fingers and toes constrict excessively in response to cold temperatures or stress. This leads to reduced blood flow, causing the affected areas to turn white or blue and feel cold or numb. During a Raynaud's attack, the skin may eventually turn red as blood flow returns. The duration and severity of these attacks can vary from person to person. While often not serious, frequent attacks can lead to complications, so it's important for individuals experiencing symptoms to consult a healthcare professional.