Daytime temperatures are expected to be normal to below normal in most parts of the country except parts of southern peninsular India, northeast and northwest India, according to the India Meteorological Department (IMD) forecast.
Night temperatures are expected to be higher than normal in many parts of the country.
Parts of northwest India, along with some parts of central India, adjoining areas of peninsular India and southern parts of northeastern India, are likely to see normal to below normal temperatures.
May is expected to be a milder month mainly due to an increased likelihood of thunderstorm activity in several parts of the country and an increased frequency of western disturbances.
India Meteorological Department (IMD) officials said they have noticed an increase in WDs since March; The incursion of moisture from the Arabian Sea has enhanced the WDs.
There are likely to be higher than normal heatwave days over some parts of the Himalayan foothills, the east coast states, Gujarat and Maharashtra in May.
Average rainfall during May, nationwide as a whole, is likely to be above normal (>110% of LPA). The long-term average rainfall over the country as a whole during May based on 1971-2020 data is about 61.4 mm. Normal to above normal rainfall is likely over most parts of the country except some parts of eastern and northeastern India and east-central India where below normal rainfall is likely.
Read also: Rain and stormy winds to calm the heat wave in the region: IMD
Currently, neutral El Niño conditions are evolving towards El Niño conditions over the tropical Pacific Ocean, the IMD said. There is a 60% chance of El Niño conditions developing during May, June and July, according to IMD forecasts.
El Niño conditions are expected to continue during the monsoon season until the end of the year.
At present, neutral Indian Ocean Dipole (IOD) conditions prevail over the Indian Ocean. The latest climate models indicate that positive IOD conditions are likely to develop at the end of the monsoon season.
El Niño and La Niña are opposite phases of the El Niño-Southern Oscillation (ENSO), a natural climate cycle driven by changes in ocean surface temperatures in the central and eastern tropical Pacific Ocean.
El Niño, the warmest phase, typically occurs every two to seven years, lasts about nine to 12 months, and is associated with drought in Australia, Indonesia, and parts of South Asia, and increased rainfall in parts of southern South America, the southern United States, the Horn of Africa, and Central Asia. In India, the El Niño phenomenon depletes the monsoon rainy season. Positive IOD helps enhance monsoon.
“We expect more thunderstorms and more thunderstorm activity in May. This is not necessarily linked to the development of El Niño,” said M Mohapatra, Director General, IMD.
During May, higher than normal heatwave days (3-4 more days) are likely over some parts of the Himalayan foothills especially southern Himachal Pradesh, Uttarakhand, northeastern Bihar, east coast states, Gujarat and Maharashtra.
The IMD extended range forecast shows that there is likely to be above normal rainfall activity especially over east and northeast India till May 7. Daytime temperatures are expected to be high over northwest India during the second and fourth week of May.
During April, the country’s rainfall was 11% below normal; 7.4% increase over northwest India; 10.8% below normal over eastern and northeastern India; 17.2% increase over central India and 51.1% decrease over the southern peninsula.
IMD forecasts indicate that southwesterly winds are expected to blow over the Bay of Bengal in the week of May 14-20. The monsoon usually arrives over the Andaman Sea around May 20.
