Eye on sky for new rain low

Monsoon 2010 is leading the race for the worst rain count in the city in four decades.

If July was dismal and August the driest this decade, the September sky doesn’t look very promising yet. That brings 2010 within sniffing distance of Monsoon 2009’s record as the worst since 1972.

The city received only 869mm of rain during the entire monsoon last year. This year’s count on the monsoon meter is 636mm so far.

“The total August rainfall (see chart) recorded by the Met office this year (179.1mm) was very low (only 54.5 per cent of the long period average) despite a favourable forecast,” said Gokul Chandra Debnath, the director of the Regional Meteorological Centre at Alipore.

The weatherman attributed the low rain count to the lack of low-pressure formations.“The main reason for the low rainfall count in August was the absence of low-pressure formations near south Bengal. There was none in the month that was close enough to the city to influence the weather here,” Debnath explained.

The little rain that the city received last month was caused by localised thundercloud cells that were strong enough to trigger only scattered showers.

So even if the city beat the long-period average in terms of the number of rainy days in August — 22 out of 31 against an average of 17.2 days — the sum total was dismal with less than 5mm of rain being recorded on 12 of these days.

“If 97 per cent of the total rainfall in the month came in seven days, it’s easy to gauge how below-par the rest of the month has been,” said O.P. Sharma, the chief meteorologist of a private Met agency.

“Even in July, over 40 per cent of the entire month’s rain came on the last day. The performance of the monsoon in July and August, traditionally the wettest months of the year for Kolkata, doesn’t augur well for the rest of the season,” he added.

Weather scientists said September would receive rain through the month but not enough.“The month-end reading is likely to end up below the long-period average, which means the 2009 record is in danger,” said a scientist at the National Centre for Medium Range Weather Forecasting in Noida.

“September is very unlikely to make up for the deficit in July and August,” he added.

Debnath said no heavy rainfall was expected within the first 10 days of September. The city usually receives 295.9mm of rain over 13.4 rainy days in September.

The monsoon hit town five days behind schedule on June 13. Although it has rained frequently since, barely seven days have been washouts.

The monsoon usually lasts till the first week of October in the city with over 1,400mm of rain and around 65 rainy days over the entire season.


Meghdeep Bhattacharya, The Telegraph Metro