# Extreme heat during Hajj

The massive pilgrimage to Mecca often coincides with periods of intense heat, posing significant challenges to pilgrims and frequently leading to injuries and deaths. Extreme heat incidents during Hajj have led to numerous health crises in different years, including heat exhaustion, heat stroke, and dehydration, sometimes resulting in fatalities.

## Background

Much of the pilgrimage and many of the rituals that occur during the Hajj are performed outdoors and on foot and by elderly people, making pilgrims more susceptible to the intense heat present in Mecca during the summer. Outdoor rituals include standing on the plain of Mount Arafat for a full day from sunrise to sunset, and walking for several hours in the outskirts of Mecca on other days. The stress put on pilgrims due to heat has been exacerbated by increases in regional temperatures induced by climate change, which Saudi researchers claimed represented an average rise of dry-bulb temperatures by 0.4°C each decade, and wet-bulb temperatures by 0.2°C per decade.
The March 2024 study published in the Journal of Travel Medicine stated that both these temperatures were strongly correlated with increased heat stroke and heat exhaustion, and that Hajj dates that coincided with Mecca's "hot cycle" in May through September led to greater risk to pilgrims. Hajj pilgrimages that occurred between 1982-1995 and 2015-2024 fell within the hot cycle of Mecca. During the 1982-1995 hot cycle, rates of heat stroke and heat exhaustion peaked at 134.2 and 858.8 per 100 000 pilgrims respectively, both occurring in August 1985 where the average daily wet-bulb temperature during the Hajj was 25.1°C. The average daily wet-bulb temperatures during Hajj between 1979 to 2019 exceeded the US National Weather Service danger threshold of 24.6°C on 38 days, nearly half of which took place in 2015-2019. The study also showed that Hajj pilgrims from countries with colder average temperature were 4.5 times more likely to die than local pilgrims.
Attempts to mitigate the heat include portable water stations and misting systems, as well as expansive air conditioning in the floor of the Great Mosque of Mecca and in surrounding tents. This contributed to a 74.6% reduction in heat stroke cases and a 47.6% decrease in fatality rate compared to the prior 1982-1995 hot cycle, but still represented greater rates compared to the prior cold cycle.

## 2020s
### 2023

In 2023, temperatures reached 48°C (118°F), leading to at least 8,400 pilgrims suffering from heat-related illnesses, with the actual number likely being much greater due to the number of unreported cases.

### 2024

Roughly 1.8 million Muslims attended the Hajj in 2024, with temperatures in Mecca reaching above 46°C (114.8°F) on 16 June 2024, and reaching 52°C (125°F) on 17 June 2024. Medical personnel had to treat at least 2,764 pilgrims due to heat-related illness on 16 June 2024 alone. Jordan's foreign ministry reported on 16 June 2024 that 14 Jordanian pilgrims died after suffering from heat stroke due to the extreme heat, and that 17 more pilgrims were missing.
These deaths followed predictions from the Saudi national meteorology center stating that temperatures in Mecca and Medina during the Hajj would be 1.5 to 2 degrees Celsius above typical temperatures for mid-June. In response to this, the Saudi health ministry issued a heat advisory requiring pilgrims stay hydrated and avoid outdoor activities from 10:00 to 16:00 Arabia Standard Time, while also recruiting workers to distribute water and give advice on protection from the sun and excessive heat.