Direct answer: The Northern Lights are not something that can be counted in fixed days; their visibility depends on solar activity, local darkness, and clear skies. In practice, strong displays occur during periods of higher geomagnetic activity and in locations with dark, northern skies, typically from late autumn through winter in high-latitude regions. Instead of a fixed number of days, forecasts provide hourly/minute-by-minute chances for given nights. If you share your location and a date range, I can give you a practical forecast window and tips to maximize your chances.