Pakistan deluge: 500% more rain in some provinces

The rain between July 1 to July 13 in Pakistan’s Sindh province saw a 625 per cent departure from the 30-year average, while Balochistan saw a 501 per cent departure. The rain spell has wreaked havoc in the country, reportedly killing 147 people. 

Experts said the downpour in the June-July 2022 period was unusual and expected more rain in the coming days. The monsoon season runs from July to September in the region. 

Pakistan’s Federal Minister of climate change, Sherry Rehman, put out the data on the microblogging site Twitter. Overall, the country received 57.8 millimetres of rainfall till July 13, a 194 per cent departure from a normal of 19.6 mm. 

Heatwaves were recorded in the country in mid-March, according to ReliefWeb, a humanitarian information portal.

The overall rain for Pakistan in June was 67 per cent above normal. Pakistan Meteorological Department reported moderate to heavy rainfall for most of Khyber Pakhtunkhwa and Punjab. 

Arid regions such as Balochistan and Sindh were severely hit, recording 57.8 mm and 98.3 mm, respectively. 

Padidan and Mirpur Khas cities in Sindh saw daily highest rainfall of 122 mm and 56 mm on July 8 and July 5, respectively.

Takht Bai, an administrative division located in Khyber Pakhtunkhwa, recorded 170.30 mm of rainfall. This is the highest amount of rain the area has ever received in 24 hours in recorded history. 

The rains breached at least ten dams in Balochistan, reports suggested. Floods battered Quetta, the capital of the province, and as many as 77 people were reportedly killed. 

Urban flooding was reported in the cities of Quetta, Pasni and Turbat, Rehman told Dawn. She also called the situation a “natural calamity”.

What caused the downpour?

A low-pressure area developed in the Bay of Bengal, leading to the rain, meteorologist Mahesh Palawat told Down To Earth. He is the vice-president of Meteorology And climate Change at Skymet Weather, a private Indian company that provides weather forecasting services. 

“The pressure area is moving to Odisha, Chhattisgarh, north Telangana and south Madhya Pradesh going up to Gujarat, Sindh and Balochistan,” he explained.

Usually, one or two low-pressure areas develop across central India in a month, he said. “But now a series of them are developing, which can be attributed to climate change,” Palawat said.

He added that rain activity would be very intense in central India. “These weather systems are also approaching Balochistan and Sindh, so these areas will also get rains,” he added. 

This monsoon may be the rainiest one in the region, he predicts.

Winds moving in the south-west direction, also called southwesterly winds, are extending right up into parts of Pakistan past Gujarat, Raghu Murtugudde told DTE. He is a professor in the department of atmospheric and oceanic science and Earth system science interdisciplinary center at the University of Maryland. 

These winds are running into ones from the north around the Himalayas. Together they are forcing a cyclonic circulation — circulating winds caused by a low-pressure area, he said.

More rain on the way

According to experts, cyclonic circulations can hold a lot of moisture, triggering heavy rainfall.

Another contributor is the formation of troughs found near low-pressure areas. It causes air to rise, leading to rainfall.

A deep trough is also extending up to Balochistan and south Pakistan, Palawat said. This is an offshoot of intense western disturbances, which provide moisture. 

Murtugudde expects heavy rains to continue over some of these regions for a few days.

Pakistan’s meteorological department predicts urban flooding in Karachi, Hyderabad and a few other regions from July 14 to 17. Flash floods and landslides are also expected in some parts of the country.

On July 12, Jason Nicholls, lead senior meteorologist at AccuWeather, an American weather forecasting company, predicted that an active monsoon would continue across India into Pakistan through the weekend. 

“The low-pressure area off Odisha coast can reach a depression before moving ashore later this week. Another low will form off the Gujarat coast around July 14,” the expert tweeted, adding more flooding rains were likely to be in Gujarat in the next few days.