analysis of heat waves in iran: patterns, trends, and characteristics in frequency, intensity, and duration (1980-2024)

The increasing frequency and intensity of heat waves represent a pressing climate challenge globally. this study examines the patterns, trends, and characteristics of heat waves across 178 synoptic meteorological stations in iran from 1980 to october 2024. utilizing the heat wave magnitude index (hwmi), defined as periods where daily maximum temperatures exceed a specified threshold for three consecutive days, we observed a dramatic rise in heat wave occurrences—112.4%, 161.6%, and 391.1% in the second, third, and fourth decades compared to the first (1985-1994). annually, approximately 28 heat waves were recorded, with an average magnitude of 6.4 and a duration of 23.8 days, particularly prevalent in the mountainous regions of the zagros and alborz ranges. this rise in heat waves in mountainous areas during colder seasons may be linked to feedback from reduced snow cover. the most severe heat wave occurred in summer 2024, marked by significant atmospheric features such as the clockwise rotation of the upper subtropical high's ridge line and intensified thermal low pressure in central iran. these findings highlight the urgent need for adaptive resource management and climate resilience strategies. policymakers should prioritize improved monitoring and predictive modeling to prepare communities for the growing impacts of extreme weather events, ensuring effective responses to the challenges posed by heat waves in iran. the increasing frequency and intensity of heat waves represent a pressing climate challenge globally. this study examines the patterns, trends, and characteristics of heat waves across 178 synoptic meteorological stations in iran from 1980 to october 2024. utilizing the heat wave magnitude index (hwmi), defined as periods where daily maximum temperatures exceed a specified threshold for three consecutive days, we observed a dramatic rise in heat wave occurrences—112.4%, 161.6%, and 391.1% in the second, third, and fourth decades compared to the first (1985-1994). annually, approximately 28 heat waves were recorded, with an average magnitude of 6.4 and a duration of 23.8 days, particularly prevalent in the mountainous regions of the zagros and alborz ranges. this rise in heat waves in mountainous areas during colder seasons may be linked to feedback from reduced snow cover. the most severe heat wave occurred in summer 2024, marked by significant atmospheric features such as the clockwise rotation of the upper subtropical high's ridge line and intensified thermal low pressure in central iran. these findings highlight the urgent need for adaptive resource management and climate resilience strategies. policymakers should prioritize improved monitoring and predictive modeling to prepare communities for the growing impacts of extreme weather events, ensuring effective responses to the challenges posed by heat waves in iran.