Karachi experienced an unusual event on the night of February 3rd. Intense downpours originating in the northern part of the city quickly enveloped other areas, significantly inundating portions of the metropolis. The rain itself did not come as a surprise as it was well forecasted in advance that a strong extratropical storm will impact the country during the 1st week of February leading to heavy thunderstorms across the Makran coast in Balochistan.
But we were taken aback due to the severity of the rain that actually unfolded in Karachi because it is a phenomenon not commonly observed in the winter season.
With 75 mm of rain recorded at Faisal Base, it came near the all-time high of 96 mm set at Karachi Airport on February 19th, 1979 (keep in mind average rain is only around 7 mm). However, 51 mm was recorded at the Airport, hence technically no record was broken. The winter rain’s intensity was on par with a typical monsoon rainstorm as it occurred in a span one hour to 1.5 hours. We have repeatedly stressed that Karachi’s rain rate can be very heavy to extremely heavy, transpiring within a time frame of a few hours i.e 1 to 1.5 hours (Reaching from 50 mm to 100 mm).
The rain bore all the hallmarks of a strong moisture incursion from the Arabian Sea, an alarming behaviour becoming common since the monsoon of 2007 as it showcases how climate change is altering Karachi’s precipitation. But witnessing such a pattern in winter is a first of its kind in recent memory.
The last occurrence of such conditions in the winter season dates back to December 4, 2006, when 51 mm of rainfall also brought the city to a standstill (below is the picture).
What is interesting is that February’s rainstorm in Karachi comes at a time when the global sea surface temperatures are at their peak, much of which is being fueled by the ongoing El Nino event.
Hence, the possibility that the ‘warming’ Arabian Sea might have ignited the February 3rd rain leading to a typical monsoon-style downpour – a rarity in the winter season but does it mean that it will become a norm like it has in the summer season?
Similar content that sheds light on Karachi’s changing rain pattern
Pakistan Weather Portal (PWP) 