March has brought news of rain from almost the entire country with many regions, particularly Central and South India already breaking age old rain records. So is there something unique about rain in the month of March that makes it this eventful a month or is it just another freak year where incidents of unusual weather will become common? Let’s find out but let’s start with understanding the nature of rain in March.
It always rains in the evening - A bright and an extremely warm and sunny day suddenly turns into a cold, windy, cloudy and a rainy one. So why does it always happen in March and why does it always rain in the evening? Well, more often than not, rain in India in March occurs towards the later part of the day as the temperatures reach their highest point, leading to a sudden build up of thunder clouds (cumulonimbus clouds). Thundershowers are short spelled but give good amounts of rain in just about 2 to 3 hours.
Rain in Odisha on 3rd March, though lasted only for two hours to three hours, gave around 40 mm of rain in Bhuvaneshwar in a day, the highest the city received in 5 years.
Winds and Hail - While rain in the winter in India is calm and peaceful, rain in March is quite the opposite. Thunderstorms, sometimes quite severe are common. Winds are strong and reach up to 50 kmph, also exceeding 70 kmph on occasions. Heavy rain accompanied by hail is observed at certain times in certain locations but is highly uncommon in most. This year, hailstorms in parts of country, has been a talk of town, for all the infamous reasons.
Heavy rain accompanied by lemon sized hail in Nagpur on 2nd March, damaged orange plantations worth hundreds of crores.
In another incident in Hyderabad on Monday, 4th March, heavy rain and hailstorm, highly uncommon, claimed the life of one and also damaged standing crop of wheat and jowar. Further winds gusting up to 80 kmph in some places around Hyderabad uprooted trees and electric poles.
Weather systems - It's common knowledge that particular weather systems could and would lead to rainfall in certain areas, but what many of us do not know is the fact that the month of March is famous for frequent rainy changes in the weather in Central India as well as the weather in South India due to a number cyclonic circulations which form in these regions.
The notorious Western Disturbance which affects the weather in North India in the winter, takes a back seat in March and gives rain only if it happens to merge with any other system, (again a circulation) in the plains. Yesterday's rain in Delhi / NCR and Haryana occurred due due to this exact reason.
Therefore, in short, weather systems called cyclonic circulations or anti-cyclonic circulations govern the weather in March.
Uniqueness this year - According to latest weather update by Skymet’s Meteorological Division, rain in the month of March is common but what is not common is its frequency, severity and duration this year.
Past records show, cyclonic circulations (particularly in Central India) giving plenty rain were not seen forming at all and rain figures used to vary less. But changes in weather have led to formation of these circulations more often and more frequently than ever. “What is also very unique is, small weather systems forming in multiple locations and persisting for too long a period, resulting in heavy downpour in the first week of March, inspite of the second or the third”, says G.P Sharma of the Skymet Meteorological Division.
Photo by rajasthanvoice.
