What hot flashes actually are
Hot flashes are brief episodes of sudden warmth, flushing, and sweating that spread over the face, neck, and chest. They can happen any time of day or night (as night sweats), and typically last between 1 and 5 minutes.
"Up to 80% of women experience hot flashes during the menopause transition — they are the hallmark vasomotor symptom."
Source: North American Menopause Society (NAMS) position statement on vasomotor symptoms.