Southwest Monsoon usually makes an onset on June 1 over Kerala, but invariably, either it is a little early or slightly late.
This time, Southwest Monsoon 2019 while did arrive early over the Bay Islands, but was delayed by a week over Kerala, on June 8. Taking a look at the Monsoon arrival in the past, the latest onset date is June 18, 1972 while the earliest onset was on May 18, 2004.
Talking about the Monsoon onset between 1971 and 2019, there have been eight occasions, when Monsoon arrived over the mainland on or after June 8, including the years 1972, 1979, 1983, 1995, 1997, 2003, 2016, and 2019.
Weakest Monsoon in June Likely
Out of these eight years, only two years have seen normal rains in the month of June. In June 1972 the country saw 123.3 mm, 1979 140.5 mm, 1983 150.8 mm, 1995 143.3 mm, 1997 171.7 mm, 2003 166.6 mm, and 2016 174.6 mm,
The rest of the years as can be seen have seen below normal rains. This year, until June 20, the country has seen 53.8 mm, against 94.3 mm making it 43 percent deficient.
The lowest June rains were seen in 1972, at 123.3 mm, and to match that also, rest of June should have normal rains, which does not look like a possibility this time. This year, it may be the weakest and lowest June ever in terms of rains. With 75.2 mm of rains left, about 7 mm rains are needed for the country each day.
Sluggish Monsoon This Year
The pace of Monsoon this year has not been as it usually is. Late onset does not mean late coverage and there have been occasions when Monsoon made an onset late, it has covered in time. The earliest onset over the country was in 2013, when Monsoon reached the entire country on June 16 despite making an onset over Kerala on June 8. It had reached parts of Uttar Pradesh on June 15 and in one day took a big leap and covered the entire country.
Monsoon pace remains alright along the West Coast and gets stuck on the eastern side. In 2015, Monsoon had reached the Dahanu region on time but was slightly in eastern parts. By June 26, it did cover the entire country. This year, it has been the other way round and Monsoon has had a very slow progress on the West Coast but has still managed to cover Northeast and reach Kolkata as of today.
Last year, in 2018, it reached Mumbai on June 9 and had covered the country on June 29, but the progress over the eastern parts was jerky. Moreover, 2017 had a timely arrival over Mumbai but it was late to cover the country, i.e. on July 19, four days later than its usual date.
Thus, Monsoon is slow or fast, and never follows a smooth pattern always having bumps in between. This time, Monsoon has remained sluggish with only 10 percent of Peninsular India witnessing the onset.
The Northern Limit of Monsoon is passing through Ratnagiri, Kolhapur, on the West Coast and central side and merely Shimoga, Salem, Cuddalore in the Peninsular region and covering Kolkata, Gangtok on the eastern side.
As of now, Monsoon is advancing along the West Coast, as the NLM did pass from Kochi first, then Mangaluru, and now Ratnagairi, further moving to Kolhapur.
However, it is dipping down Salem, Cuddalore, just a few parts of Karnataka and Tamil Nadu. On the eastern side it has just reached Kolkata until now.
However, now a fresh Low Pressure area will result in the advancement of Monsoon over a bigger chunk including interior regions of Telangana, Hyderabad, Bengaluru, rest of Karnataka including Bengaluru, most parts of Maharashtra including Mumbai, as well as Andhra Pradesh including Vizag, and some parts of Odisha.
Image Credit: NDTV
Please Note: Any information picked from here must be attributed to skymetweather.com