History in Review:18-24 June 2015- The days when Karachi burned!

Heatwaves in Karachi during the month of June are no big deal. It is quite common for the temperatures in the city to rise over 40'C for a few days every year, which usually happens since the moderator- the sea breeze- is cut off and hot, dry winds from the land invade the region.

The year 2015, however, was an exception. While the world observed the strongest El-Nino on record (apart from rising average global temperatures), Karachi experienced its hottest year ever. Usually what happens is that when the temperatures rise over 40'C, the humidity drops to below 10%, which makes the air hot and dry and the heat somewhat bearable rather than above 40'C temperatures with high humidity. A combination of high temperature and high humidity introduces the concept of "heat index", and that is exactly what makes such heatwaves deadly!
The following are the minimum and maximum temperatures along with average humidity and maximum heat index recorded in Karachi between 18 and 24 June 2015:

18 June: Min 29'C, Max 39'C, humidity 52%, heat index 44.3'C
19 June: Min 31'C, Max 41'C, humidity 48%, heat index 43.6'C
20 June: Min 32'C, Max 45'C, humidity 45%, heat index 49.4'C
21 June: Min 33'C, Max 43'C, humidity 37%, heat index 44.6'C
22 June: Min 33'C, Max 42'C, humidity 42%, heat index 46.7'C
23 June: Min 32'C, Max 41'C, humidity 47%, heat index 45.8'C
24 June: Min 30'C, Max 37'C, humidity 62%, heat index 44.3'C

Very hot and muggy weather gripped the metropolis from 18 June and the temperatures and humidity continued to rise with each passing day. By 20 June, the temperature had risen to a blistering 45'C. Heat index on this day was almost of 50'C and the fact that Ramazan had started just a day before aggravated the things further. The use of air conditioners increased drastically as the agonizing heat failed to abate, causing a massive surge in power demand, causing the power feeders and transformers across the city to trip and burn out one after another (despite the fact that there was no major breakdown on a grid level). That is when the situation got completely out of hand and the heatwave started claiming lives. No locality of the city was spared from the wrath of electricity failures and most areas reported power outages spanning over 24 hours on average.  My own area (although exempted from regular load shedding) suffered a 20 hour power breakdown at a stretch as the area transformer broke down and was eventually replaced. We literally spent the night roaming around in the car with the AC on to provide some sort of relief from the relentless heat which refused to abate even after the Sun went down! The next day, we went to our relative's place to spend the day, with the hope of finding electricity there, but we were greeted by recurrent electricity breakdowns on our arrival!

It was literally unbearable to sit even in the fan, and although I am not particularly fond of AC, but those were the days when AC became the necessity instead of luxury! The very walls of our apartment building were radiating heat, and our usually cool and well-ventilated rooms had turned into furnaces- something of sort that I had never witnessed before, although this was not the first time Karachi experienced 40+'C temperatures.

The entire city was in chaos as the death toll continued to rise. By the end of the week, the official number of people who succumbed to the heat had risen to 1264, however this does not account for the deaths that occurred at homes. If those are taken into consideration, the number of people who died in the city due to the heatwave directly was over 2000.
With such a high death toll within a span of week, the graveyards ran short of space for the people to bury their loved ones, and many of the bodies had to kept at morgues. Unfortunately, they too began to run short of space.

As is obvious from the minimum temperatures mentioned above, the nights refused to cool down due to factors such as high humidity, congestion, urban development and lack of vegetative cover.
Other than the fact that people were fasting and had to face prolonged power cuts, what made this heatwave lethal for a metropolis of 16 million was the heat index. The humidity, that usually drops below 10% when the temperatures rise above 40'C, was this time well above 30%, pushing the dew points high and raising the heat index to magnanimous proportions, leading to such a catastrophe. 

Rainfall update:
On 21 June, localized developments occurred. In the afternoon, few areas in district central and west received some showers from clouds that came from North, and from similar development in the evening before Iftar, parts of district east received brief showers from clouds that came from east, while it drizzled in southern areas. No reading for rainfall was received, however localities that received showers accumulated an amount of around 2-3 mm, such as Paposhnagar, where 2 mm rain was recorded (Credits: Waseem Ahmed).