Unseasonal Storms Devastate Karachi, US Heatwave Shatters Records
Unseasonally wet weather struck southern Pakistan and north-west India on Wednesday, bringing heavy rain, thunderstorms, hail, and strong winds. This rare March event caused significant disruption and tragedy, particularly in Karachi, Pakistan's largest city.
Karachi Particularly Badly Affected
Karachi was hit hardest, with local recordings showing more than 50mm of rain and winds gusting up to 60mph. The severe weather led to walls, buildings, and a pedestrian bridge collapsing, widespread flooding, and power outages across the city. At least 18 people were killed and several more injured, with many casualties resulting from structural collapses. Other deaths were attributed to a fallen tree and a lightning strike.
Heavy rain is exceptionally rare in this region at this time of year, as the majority of annual rainfall typically occurs during the monsoon season between June and September. The average March rainfall in Karachi is only 15.7mm, making this event particularly unusual and devastating.
Impact on Neighbouring Indian Provinces
Storms were less intense in the neighbouring Indian provinces of Gujarat and Rajasthan, with most areas receiving no more than 15mm of rain. However, the city of Rajkot recorded 38mm. Disruption was still felt, with some power outages and minor damage to trees and buildings. Of greater concern is the impact on local agriculture, as farmers raised alarms about potential crop damage and disruption to impending harvests. March is usually one of the driest months in north-west India, with most of Gujarat averaging less than 1mm of rainfall and large parts of Rajasthan no more than 5mm.
Historic Heatwave Hits Western US
Meanwhile, large parts of the western United States have been gripped by a heatwave that intensified through the week, with temperatures expected to peak on Friday and Saturday. This extreme weather event has been caused by a meandering jet stream and an almost stationary area of high pressure. These atmospheric anomalies trapped a warm flow of air from the south, and with clear skies, the air became increasingly hot as it was heated by the sun, a phenomenon often referred to as a heat dome.
Maximum temperatures widely exceeded 30°C across the south-west, about 10-15°C above the seasonal average. On Thursday, temperatures soared to 42.2°C in Indio, California, with many individual weather stations breaking March records. Phoenix, Arizona, is expected to see temperatures above 40°C for three consecutive days from Thursday to Saturday, potentially shattering the city's March record and even surpassing its April record. Denver, Colorado, is forecast to surpass 30°C on Saturday, nearly 20°C above average for this time of year.
This heatwave is anticipated to persist into next week and propagate eastwards, bringing much of the United States under exceptionally warm weather by the middle of next week. The combination of these extreme weather events in Pakistan, India, and the US highlights the growing unpredictability and severity of global weather patterns.
