Monday 31 August 2015

August 2015 - Monsoon Performance, continuing to be below normal!

The South West Monsoon in 2015 is turning out to be a deficient rainfall year in Goa, in line with the deficient rainfall witnessed in the rest of the country.

As against normal area weighted average rainfall for the State of Goa  of 682 mm in August, only 515 mm rainfall was recorded, which is 24% below normal. Overall in 2015 SWM season from June 1 till August 31, the rainfall was 22% below normal. This monthly deficiency trend is seen in every month this year.


With El Nino getting stronger and failure of the Arabian Sea branch of the SW Monsoon this year, Goa received just about 50% of the rains recorded in  the month of August 2014.


 During August 2015 there were just 2 days without rainfall, but only 8 days with above normal rainfall. The rainfall was substantially below normal rest of the days.




















Places in the interiors of Goa, at the base of the western Ghats, like Valpoi, Sanguem, Sakhali etc have performed poorly in 2015, compared to earlier years, leading to the overall -22% overall rain deficiency this year.

Sanguem is the seasonal topper so far this year, being the only place in Goa to have received more than 100 inches of rainfall till August 31. It is closely followed by Valpoi, Ponda, Old Goa, Quepem and Sakhali.



The rainfall recorded at various centres in Goa month wise till August 31 is as per the chart below:



While the Selaulim Dam, with largest water holding capacity, located near Sanguem, was reported to be over flowing, other major water reservoirs including the Anjunem Dam in North Goa, were still below the maximum level.

The daily rainfall chart of Vagaries Goa at Aquem, Margao indicates the pattern of rain in August this year.





















The overall monsoon performance for India indicates a deficiency of 11% till August 31, 2015.


The failure of the monsoons throughout the west coast and in the Gangetic Plains is very telling.

Outlook for the rest of the season ending September 30th is not very encouraging. There are indications that the withdrawal of the SW Monsoon may be very imminent, if it hasn't already started from Pakistan and NW India. Click on this link, to understand the withdrawal parameters, as explained in the blog Vagaries of the Weather.

For daily updates on the rainfall all over Goa visit http://weatheringoa.blogspot.in/p/swm-2015-goa-graphs-and-charts.html