In my previous posts on monsoon I have introduced the four factors that affect the Indian monsoon. Once again, the list of the factors that affect Indian Monsoon are
1. ENSO – EL Nino southern oscillator
2. Mascarene High
3. Indian Ocean Dipole
4. Heating up of Indian mainland

There is a fifth and final factor that affects the monsoon and it happens in two phases. First phase in the last week of May and 2nd phase in mid of July. Today I will talk about the first phase of the fifth factor. That is the confirmation that we get by looking at the rainfall in 14 observational centers located in Lakshadweep, Kerala and coastal Karnataka. Minimum of 8 out of these 14 observational centers should record more than 2.5mm rain for 2 consecutive days for the declaration of the onset of monsoon.

Which are these 14 observational centers?

Here is the list with the rains recorded in last 2 days.

Lakshadweep 28th 29th
1. Aminidivi 0mm 2mm
2. Minicoy 11mm 4mm

Kerala
3. Trivandrum 12mm 33mm
4. Punalur 6mm 56mm
5. Kollam 5mm 60mm
6. Allaphy 7mm 95mm
7. Kottayam 5mm 48mm
8. Kochi 51mm 47mm
9. Trissur 6mm 0mm
10. Kozikode 8mm 19mm
11. Talaserry 1.6mm 4.6mm
12. Kannur 4mm 1mm
13. Kasargode 11.4mm 0mm

Karnataka
14. Mangalore 0mm 10mm

11 out of 14 observational stations and 10 out of 14 observational stations have recorded more than 2.5mm rain. Minimum required is 8. So since the criterion was fulfilled they waited for south westerly directional winds to bring rain today. This happened between 1PM and 2PM in Southern Kerala in Trivandrum, Kollam and Kochi districts. So monsoon arrival has been declared by IMD. Monsoon came 2 days before scheduled date of 1st June.

So, what next?

Yes, monsoon has hit Indian southern coast Kerala. Which is a very good news for India as whole. Farmers are the happiest right now as the monsoon hits India bringing cheer in their hearts. Not just the farmers, Stock Market will also celebrate this news.

Does that mean that its going to be a good monsoon?

Does that mean that monsoon will arrive before time in the whole of country. The answer is yes and no. It may it may not. There should not be a El nino, Mascere high pressure should be maintained and IOD temperature gradient should be maintained. Then only monsoon will be excess or normal. So we will have to wait and watch.

Meanwhile here are the normal dates of arrival of monsoon in different cities in India.
Trivandrum 1st June
Chennai 1st June
Coimbatore 1st June
Kochi 2nd June
Bangalore 3rd June
Vijayawada 3rd June
Mangalore 4th June
Hyderabad 6th June
Goa 6th June
Visakhapatnam 7th June
Kolkata 7th June
Pune 9th June
Mumbai 10th June
Patna 12th June
Nagpur 12th June
Ahmedabad 14th June
Bhopal 14th June
Lucknow 19th June
Kanpur 21st June
Agra 25th June
Delhi 29th June
Shimla 30th June
Srinagar 1st July
Chandigarh 1st July
Jaipur 5th July
Amritsar 10th July
Jaisalmer 15th July

India has weighted rainfall of 887.5mm for every monsoon. India in last monsoon (2016) had rainfall of 862.0mm which is 3% lesser than the standard requirement. Likewise, every place in India has standard normal rainfall that has to be met to be called as good monsoon for that state.

For example: Telangana has normal rainfall of 755.2 mm and in last year monsoon it has received 889.8mm which is 19% more than the required making it excellent monsoon.

Next up is the arrival and withdrawal of the Monsoon. Monsoon covers the entire India by 15th July and starts withdrawing from 5th September. This withdrawal process goes on till 15th October which is the last day and that’s when monsoon exists India through Andhra Pradesh and Karnataka.

In the pictures added you can see the standard rainfall for each state and the actual performance of Monsoon 2016 and in the second picture you can look at the arrival dates of Rainfall in India across the states.

Wishing that the Monsoon stays long and give plenty of rain which will help farmers prosper and in turn help in India economic growth and also serve to the world by improving Agro-based exports!

#Monsoon #India #SriramGurujala 

http://www.imd.gov.in/pages/monsoon_main.php