‘Phailin’s wind speed exceeds that of 1999 super cyclone’

Where India Met office differs from private forecasters

By Aparna Pallavi
Published: Saturday 12 October 2013

Akshay Deoras, Nagpur-based  severe weather forecaster from METD Weather, a private weather forecast firm, says that Phailin cyclone is category 5 on the Saffir Simpson Hurricane Wind Scale, which indicates storms with wind speeds exceeding 251 km per hour.

“It is difficult to predict the exact wind speeds,” says he. “But a wind-speed of 260 km per hour can be expected at landfall (time when the eye of the cyclone reaches land) in Gopalpur and Behrampur in Odisha. The impact is likely to extend from Srikakulam in Andhra Pradesh to the Puri beach,” he adds. This wind-speed, he says, is slightly higher than the 1999 Super Cyclone which hit Odisha.
Phailin’s likely impact

A cyclone of this intensity, said Deoras, is known to be very destructive. “The affected areas can expect heavy rainfall of about 200 to 300 mm or even more, and the wind speeds will instantaneously start uprooting trees and destroying hutments and shacks. Power-lines will also snap.” Incessant rains are also expected to inundate areas, making evacuation and rescue work difficult.

Apart from this, he says, a storm surge (wall of water rising out of the sea) of 10-15 feet (over 4 metre) can be expected. “This can be very dangerous as anyone around on the coast will be killed instantly.” If there are ships at sea, they too will be beaten back, he says.

Another factor that can be expected to make the cyclone more destructive is that landfall will occur in the evening and the storm will continue all night and into morning. “Night cyclones are more dangerous than day cyclones because both evacuation and rescue work will be very difficult at night, especially in case of inundation,” says he.
He says the hurricane is likely to move inland as far as the Uttar Pradesh foothills.  “Areas like Bihar, Jharkhand and Eastern UP are likely to experience heavy rains and strong winds, but the intensity will decrease rapidly as the hurricane moves inwards.”

IMD predictions: how accurate?

Deoras says that the India Metrological Department (IMD) appears fully equipped to predict such extreme weather events accurately. “Its performance has been excellent as far as the current cyclone is concerned,” he says, “On October 9, they had predicted that the cyclone will move towards Behrampur, and that is exactly where it is headed.”

He says that METD and the IMD were using the same methods for prediction. “The only difference is that the IMD uses qualitative categories like depression, cyclonic storm, severe cyclonic storm, very severe cyclonic storm and super-cyclone to describe the wind intensity, whereas at METD, I am using the Saffir Simpson Scale, which has just two descriptive categories – tropical depression and tropical storm, which are followed in ascending order by the categories 1 to five based on wind speeds. This quantitative scale measures the severity of the storm much more precisely than qualitative assessments.”


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