After remaining subdued since the start of March temperatures started to go up North over the Indian sub continent this week just as most parts of the country started celebrating the new year according to the traditional Indian calendar. The names may be different in the form of Bisu Parba by the Tulu community of Karnataka, Bizhu, Bohag Bihu, Buisu, Bwisagu, Sangken in the Northeast parts of the country, Poila Boishakh in the Greater Bengal areas, Mesha Sankaranti in parts of Uttrakhand and among Nepalis, Pana Sankranti in Odisha, Puthandu in Tamil Nadu and Vishu in Kerala.
But even this shift to the warmer regime has not been exactly text book with parts of East Coast of India facing the brunt of heat wave for the past couple of days all the way from Coastal Andhra Pradesh to Gangetic West Bengal. Many places recorded 42°C or more with Baripada in Odisha recording 43.5° on Thursday and 44°C on Friday. Down south Kurnool recorded 42.7°C and Nandigama recorded 42.6° on Thursday while Nandyal recorded 42.6°C on Friday. Though Tamil Nadu still has not yet got into the groove this summer places like Salem, Erode & Karur Paramathi crossed 40°C for the first time this year.
If one were to look at long term ensembles there is a clear pattern that is seen emerging for this year’s summer. The traditional heat sink zones of the Indian subcontinent over NW India and adjoining areas of Pakistan seem to consistently see near normal or slightly below normal temperature forecasts for the remaining days of summer season (March to May as classified by IMD). While this in no way indicates the absence of summer over these regions as the average day time maximum temperatures during the month of May in NW India and adjoining areas can be as high as 44 / 45°C during normal times.
But the pattern seems quiet clear with except for the last week of April the rest of the summer season is likely to see the East Coast along with Peninsular India witness anomalously warm temperatures with the second fortnight of May promising to be the hottest spell of the summer season. If one looks at the precipitation anomaly charts for the remaining days of summer season there is a fairly high confidence among the ensembles of an overall below average summer rains for large parts of Indian sub continent, particularly over the Peninsular India & East Coast. In a way it also indicates the reasoning behind anomalously warm temperatures due to overall drier weather conditions.
With MJO expected to remain unfavorable for the Indian Sub continent until possibly mid May there is fair chance for these ensemble weather forecasts to come true for the next 2 / 3 weeks as indicated by weather charts. All in all it appears this year Summer has decided to keep its attention focused on the East Coast and Peninsular India. While it may not translate into more heat waves it is certainly going to be an uncomfortable summer for these regions.