Monsoon is yet to make an onset in Kerala, the India Meteorological Department (IMD) said on Tuesday. IMD had forecast on May 15 that the southwest monsoon is likely to set in over Kerala on May 26 with a model error of ± 4 days.Isolated heavy to very rainfall likely over East & Northeast India during next 2-3 days and over Kerala and Tamil Nadu on Tuesday. (Kerala Tourism website)Though there has been rainfall recorded in several stations in Kerala between Sunday and Monday, the official criteria for monsoon onset to be declared has not been met yet.After May 10, if 60% of the available 14 stations enlisted including Minicoy, Amini, Thiruvananthapuram, Punalur, Kollam, Allapuzha, Kottayam, Kochi, Thrissur, Kozhikode, Thalassery, Kannur, Kudulu and Mangalore report rainfall of 2.5 mm or more for two consecutive days, the onset over Kerala will be declared on the second day, provided the depth of westerly winds is maintained and cloudy or overcast conditions continue.IMD’s extended range forecast shows widespread rainfall over the southern parts of the west coast between May 28 and June 4.“So far, the wind profile or outgoing longwave radiation (OLR/measure of cloudiness) has not been met. The rainfall criteria has also been met only for a day. Rainfall should last for two days. The clouds have moved away from the region. It is mainly because there is a cyclonic circulation over southcentral Arabian Sea which is pulling the moisture towards itself. I do not think monsoon onset will happen during the next four days. It is likely to take place once rainfall picks up,” said Mahesh Palawat, vice president, climate and meteorology, Skymet Weather.Also Read:Intense heat, warm nights with no respite: What’s driving the extreme heatwave in IndiaIMD said that the conditions are favourable for further advance of southwest monsoon into some more parts of southwest and southeast Arabian Sea, southwest, southeast and eastcentral Bay of Bengal and remaining parts of Andaman Sea during next 2-3 days.Isolated heavy to very rainfall likely over East & Northeast India during next 2-3 days and over Kerala and Tamil Nadu on Tuesday.Heatwave to continueHeat wave to severe heat wave conditions likely to continue over Central and Northwest India during the next 3-4 days, IMD said.There is likely to be a reduction in maximum temperatures and abatement of heat wave conditions are likely from May 29 onwards, IMD has said.Maximum temperatures were in the range of 43-47°C over parts of Northwest India, Central India, adjoining Uttar Pradesh, East and north Peninsular India on Monday and 40-43°C over the remaining parts of the country except parts of Northeast India, Western Himalayan region and west south peninsular India. The highest maximum temperature of 47.6°C was reported at Banda in Uttar Pradesh, and Brahmapuri in Maharashtra.Heat wave conditions are very likely in isolated/some pockets over Punjab, Haryana, Chandigarh, Delhi, East Uttar Pradesh till Thursday with severe heat wave conditions in some pockets over Punjab on May 27; Haryana, Chandigarh, Delhi and Uttar Pradesh on Wednesday.