Our neighbourhood weatherman
Since 2015, Chennaiites have grown to keenly follow everyday weather. There has thus been a boom in weather blogging sites as well. Weather bloggers have become a bridge between the Indian Meteorological Department (IMD) and the common man, as they successfully connected with the common people in explaining different phenomena and providing updates on various social media platforms in real-time.
Adyar Times spoke to our neighbourhood weather blogger V.V.Prasad. Here are the excerpts:
Tell us something about the topography and weather of Chennai.
Chennai, situated on the east coast, gets the majority of its rainfall from October to December from the North-east monsoon (NEM). During the South-west monsoon (SWM), from June to September, most of Tamilnadu being in the rain shadow of Western Ghats, gets very less rainfall while the country gets heavy rains.
However, Chennai being a coastal city, during SWM, gets sea breeze induced convective rains (popularly known as veppa salanam rains. Thanks to the word termed by Regional Meteorological Center, Chennai). Also Chennai being in a convex coastline helps to enhance inland convergence and increase convective development related to the sea breeze.
So the whole of India is fed by the SWM, but Tamil Nadu is not?
Yes, some parts of Tamil Nadu still get plenty of rains from the SWM, i.e the parts that fall on the Windwards side of the Western Ghats thanks to the western opening in the Ghats. Places like Avalanche, Pandalur, Devala, and Gudalur in Nilgiris get heavy rainfall during this time. Avalanche is known to get very severe bursts of rain. In 2019, it was like it was pounded with 2136mm of rain in 72hours. It was a historical and record-breaking rain as it got 820mm for 24hrs till 8th August which was followed by 911mm the very next day. It didn’t stop there and got 405mm the next day.
Chinnakallar and Valparai in Coimbatore district are also known for heavy rains during SWM. Chinnakallar in fact is one of the top 10 wettest places in the country. But things change during NEM when places like Coonoor (Nilgiris) and Kodai (Kodai Hills), enjoying the bulk of rain along with the cities on the east coast like Chennai, Karaikal, Pondy, Nagapattinam, Cuddalore, Pamban, etc.
NEM rains for Chennai are mostly system bound ones (cyclone systems) which start from the stage (categorised based on the pressure) of Low-pressure area (LPA) and with better conditions descend further to Depression, Deep depression, and later Cyclone and Severe cyclonic storm (SCS).
What are your sources of information for weather forecasting?
Indian Meteorological Department has many critical and useful maps that we use. There are also other forecast models available like Euro model ECMWF (European Centre for Medium-Range Weather Forecasts), US-based GFS (Global Forecast System), which gives us an insight into upcoming events. We have a community where we discuss the weather. Many people inside our community have the equipment (Automatic Weather Stations and Automatic Rain gauges like the Davis, Accurite, etc.) for measuring weather parameters like temperature, dew point, relative humidity, rainfall accumulation, pressure, etc., to track weather conditions, and those details are shared in the community. We also maintain the data of bloggers along with official stations to study in-depth about the rain spread.
What equipment do you have?
I have a manual rain gauge and a separate thermometer to track the temperature and relative humidity.
With the increasing popularity of weather blogging, is there any interaction with the Meteorological department?
While we do check out their updates regularly, we do reach to them for queries related to reports for our research.
Tell us something about your weathermen community.
This community consists of people interested in the weather. All of us are driven by passion. We also run daily contests on the forecast. For example, there will be a contest where we need to guess the max temperature of the day. So it keeps us engaged to monitor the conditions and forecasts based on it and how the weather forecast models indicate the proceedings and predict. By the end of the day, we check and see who was the nearest.
In earlier days, we relied a lot on nature to predict the weather, has it become redundant now, with the advent of satellites and technology?
Not at all. We still depend a lot on visual observations, which our community terms it as Naked Eye Technology (NET). For example, we look for the cloud pattern, direction of winds, etc., and try to correlate with radar/satellite pictures for forecasting or more precisely nowcasting.
Can you give us some simple tips that we can use?
It is best to check out the IMD forecast.
What are the most common questions that you are asked by people?
Some of the common questions are: Will it rain today? Can we dry the clothes out? Can I travel today? Some of the professionals who conduct outdoor shooting ask if the weather would favour them.
What got you interested in the weather?
When I was younger, my father introduced me to the clouds and their names. He explained a lot about cyclones, their stages, and developments. As I grew, my curiosity became my passion.