Weatherman forecasts pre-monsoon scorcher; heat waves to hit early

While the early indications are for a normal monsoon this year, the months of March, April and May would be warmer than normal and heat waves would hit 16 states as well as Delhi earlier than usual, the India Meteorological Department said on Wednesday.

The weather office said weather conditions over the Pacific suggest moderate La Nina conditions. This could be an early indication of normal monsoon, which augurs well for agriculture and the economy.

But before that will be the murderous heat. ''During the 2018 pre-monsoon season, warmer-than-normal temperatures are likely in all meteorological subdivisions of the country. Seasonal average temperatures over many of the subdivisions from northwest and neighbouring central India are likely to be above normal by more than 1 degree Celsius,'' IMD said in its pre-monsoon forecast on Wednesday. The pre-monsoon season is from March to May.

The weather office also warned of increasing trends in the duration and frequency of heat wave conditions in Punjab, Himachal Pradesh, Uttarakhand, Delhi, Haryana, Rajasthan, Uttar Pradesh, Gujarat, Madhya Pradesh, Chhattisgarh, Bihar, Jharkhand, West Bengal, Orissa and Telangana as well as the meteorological subdivisions of Marathwada, Vidarbha, central Maharashtra and coastal Andhra Pradesh.

''Normal to above-normal heat wave conditions are likely in the core heat-wave zone during the season,'' the IMD said.

The IMD has predicted about 52 per cent probability of above-normal maximum temperature in core heat wave zones.

The rise in temperature will not have a major impact on the current rabi crop unless there are excessive heat wave conditions. ''Overall, the impact on production will be negligible,'' the IMD said.

For wheat, the yields can drop if the temperature rise is for a long period,'' said K K Singh, head of agro meteorology at IMD. ''The grain filling period for the wheat crop is March. If the temperature is higher by 1 degree Celsius, than maturity will happen fast and productivity will be less by 200-350 kg per hectare from the average productivity of 4.5-5 tonne.''

Farmers in Punjab, Haryana and Rajasthan typically start planting cotton by May and paddy by June. In Madhya Pradesh, soybean cultivation starts after the monsoon sets in.