In the last week, two cyclones have developed on either side of the coastline- “Maha” in the Arabian Sea and “Bulbul” in the Bay of Bengal. These two systems have dampened the activity of the North-East Monsoon this month. All the five sub-divisions had experienced a surplus of rains in the month of October, but November has been a different story so far. The rains have been deficient especially in Tamil Nadu, where the North-East Monsoon is a lifeline. Chennai has recorded a meagre 3 mm of rainfall in the first 10 days of November against the normal of 374 mm. Similarly, Puducherry has received 2 mm of rainfall against the normal of 403 mm.
The clearance of “Bulbul” will gradually pave the way for the strengthening of the North-East Monsoon in Peninsular India. The remnant of the tropical storm, “Nakri” will move to the Bay of Bengal which will further accelerate the Monsoon activity after 13th November. The rainfall will be confined to Kerala, South Interior Karnataka and the interiors of Tamil Nadu in the first half of the week. In the latter half however, the rains will extend to the coastal parts of Tamil Nadu, including the capital city of Chennai.
The passage of an active Western Disturbance resulted in fairly widespread and heavy pre-seasonal snowfall in the Northern Hills. Though the skies have cleared up, the weather continues to be chilly in these parts in the wake of the system. Temperature in Delhi dropped to below 15 degree Celsius on 10th November, the lowest temperature of the season. The temperature will possibly continue to fall in Delhi in the first half of the week, dropping to below 13 degrees. Another Western Disturbance will arrive between 12th and 15th November which will cause light-moderate rains across the Northern Hills.
The remnant of the cyclone “Maha” continues to persist as a feeble circulation in the North-East Arabian Sea. This weakened system will interact with the aforementioned Western Disturbance and cause unseasonal rains in Gujarat and West Rajasthan between 12th and 15th November, which will be especially heavy on 13th and 14th November.
The cyclone “Bulbul” will move to North-East India across Bangladesh and cause scattered, light-moderate rains in the region over the next two days. Central and East India will experience generally clear skies and record slight dips in temperature.
AQI Update for Delhi
Delhi air has once again reached the category of poor to very poor at many places with average AQI of above 300 (PM 2.5) and above 700 (PM10) -Data Skymet AQI App. Isolated pockets are in severe category and the reason for increased pollution is light and variable winds. In the wake of fresh WD winds have become light and direction is also changing continuously. Due to light wind pollutants that should have been moving away have not able to disperse from Delhi, attached is the heat map of Delhi which can seen at https://www.skymetweather.com/air-quality/#/home
We expect Delhi pollution will continue to remain in very poor category until November 15th as two successive WD’s are going to affect western Himalayas. After the passage of WD, normal North Westerly winds with moderate speed will commence from afternoon of November 15. This will help in thinning down the pollutants and there will be improvement then.
Crop Sowing in Rabi Season
Due to back to back cyclonic storms “Kyarr” and “Maha” along with “Bulbul” in Bay of Bengal has raised concerns of excessive rainfall over the several parts of the country. Both Kharif and Rabi crops are affected by these changing weather conditions.
Sowing of the Rabi crop has been delayed due to incessant rains during harvesting period of Kharif season over key Rabi states.