Heatwave sapping the energy of daily wage workers, vendors and employees in Visakhapatnam

Heatwave conditions, which have been prevailing over Visakhapatnam for nearly a week, are sapping the energies of daily wage workers, vendors and employees, having to do fieldwork

Heatwave conditions, which have been prevailing over Visakhapatnam for nearly a week, are sapping the energies of daily wage workers, vendors and employees, having to do fieldwork. Though hot weather conditions are a usual feature in May, the heatwave conditions arriving in mid-April are causing anxiety among people.

Though heatwave conditions are rare in Visakhapatnam during April, they did occur for three days in April 2014, when the temperature crossed 40° Celsius at the airport, and on one day in 2018, said a spokesman of the Cyclone Warning Centre (CWC)-Visakhapatnam. The heatwave conditions are likely to prevail over coastal Andhra Pradesh during the next two days.

“A trough line generally extends from Chhattisgarh to South Tamil Nadu across Telangana, Rayalaseema or from across Odisha to coastal A.P. The shift in the trough line causes hot weather conditions and lack of rain. The dry hot winds coming from the west of the trough line result in an increase in temperatures, while the cool, moist winds coming from the East (Bay of Bengal) help in lowering the temperatures,” P.V. Rama Rao, a retired Director of the India Meteorological Department (IMD) told The Hindu on Tuesday.

“At present, hot dry winds are blowing over North Coastal A.P. from April 10 and heatwaves are occurring at a few places over Visakhapatnam, Vizianagaram and Srikakulam districts. Visakhapatnam Airport experienced heatwave from April 12 onwards with the maximum day temperatures hovering around 40° Celsius,” he says.

“In contrast, areas closer to the coast in Visakhapatnam city recorded less than 35° Celsius during these days. This can be attributed to the trough extending from interior Odisha to North Coastal A.P. The Yarada Hill, which extends up to the Dolphin’s Nose, acts as a barrier and prevents the sea breeze from directly entering into the land at Malkapuram, Gajuwaka and other areas towards the airport side. The winds from the sea have to travel up and down the hill slopes to enter these areas. This results in a variation in temperature of about 5° degrees Celsius, in different areas of the city, barely 15 km apart,” says Mr. Rama Rao.

When the actual maximum temperature recorded at a station is 45 to 46° C it is categorised as heatwave condition and if it is 47° C or more as severe heatwave. Otherwise, when the maximum temperature reaches a threshold value of 40° C at a plain station or 37° C at a coastal station, and also besides this when the recorded maximum temperature departure value is in the range of+4.5 to + 6.4° C, then it is categorised as heatwave condition. If the departure value is 6.5°C or more as severe heatwave condition.