Average Number of Cold Wave Days refers to the mean number of days in a year or season during which a region experiences cold wave conditions, based on historical weather data over a defined period. A cold wave is typically declared when the minimum temperature drops significantly below normal—for two or more consecutive days, depending on the baseline climatology of the area. The criteria may vary regionally, especially in tropical countries like India, where such events are rare but impactful.

The average number of cold wave days is an important climatological indicator used in weather forecasting, disaster preparedness, and climate change impact studies. It helps meteorologists and policymakers track shifts in temperature patterns over time and assess the vulnerability of populations and ecosystems. In regions with increasing or erratic cold wave events, this metric is critical for planning public health interventions, especially for protecting vulnerable populations such as the elderly, children, and the homeless. It also has significant implications for agriculture, energy demand, and infrastructure planning, particularly in sectors like power supply, transportation, and housing. Monitoring trends in cold wave days helps in formulating climate-resilient policies and improving early warning systems for extreme weather events.