Unusual weather system may give TN bonus rainfall

CHENNAI: The city and the rest of the state are likely to get above normal rainfall this northeast monsoon, weathermen said. The NE monsoon, which has brought moderate rainfall in the southern and delta districts on Sunday, will arrive in the city on Monday.
Weather blogger Pradeep John said, “The state is poised to get excess rainfall this NE monsoon due to a favourable Madden-Julian Oscillation (MJO).” MJO is an oceanic-atmospheric phenomenon which affects weather worldwide.
According to Skymet Weather, the MJO can be defined as an eastward moving ‘pulse’ of clouds, rainfall, winds and pressure near the equator that typically recurs every 30 to 60 days. It’s a traversing phenomenon and is most prominent over the Indian and Pacific Óceans. A wave of clouds gathers over the equatorial Indian Ocean every 30-60 days. These are the first signs of a crescendo of storms heading east. These storms are a part of the MJO.
Pradeep John said, “The equatorial wave is headed for the Indian Ocean basin. Previously, it was expected to skip our basin and remain in Pacific. Most of the rainfall this NE monsoon will occur in November and the first week of December.”
The IMD has forecast a few spells of rain in the city on Monday. Rainfall is likely to continue on Tuesday. Area cyclone warning centre director S Balachandran said, “A trough of low at mean sea level over Southwest Bay of Bengal and neighbourhood has now become an upper air cyclonic circulation over Southwest Bay off Sri Lanka coast. Chennai and its suburban areas will experience multiple spells of rain on Monday and Tuesday.”
A brief spell of shower drenched the city on Sunday night. According to Pradeep John, rainfall in the city will intensify on Monday morning.
During the 24 hours from 8.30am on Saturday to 8.30am on Sunday, Papanasam (Tirunelveli district) and Mylaudy (Kanyakumari district) received 5cm rainfall each, Kuzhithurai (Kanyakumari district) 4cm, Bhoothapandy (Kanyakumari district), Vedaranyam (Nagapattinam district) and R S Mangalam (Ramanathapuram district) received 3cm each.
As per the climatological table (1981-2010), the city gets, on average, 37cm rainfall over 11 and a half rainy days during November. During November 2016, the city received only 2cm rainfall. The temperature is likely to drop by a few degrees with the onset of the monsoon. During November, the city experiences, on average, a maximum temperature of 29.9 degrees Celsius and a minimum of 23.1 degrees Celsius.
The maximum and minimum temperature on Sunday was 32.5 degrees Celsius and 26.2 degrees Celsius, respectively. The Met office has predicted a maximum and minimum temperature of 32 degrees Celsius and 24 degrees Celsius, respectively, on Monday.
On Sunday, Nungambakkam recorded 2.5mm rainfall and Meenambakkam recorded 1.1mm rainfall.