This year the 3rd day of Garbottam ended at around 5 PM yesterday (1st January 2016). This has an impact on rainfall from 19th July to 2nd August 2016
In this period, 2 important dates are going occur this year which are crucial for determining the rainfall. One can find mention of these 2 days in Panchangam.
(1) “Aadi-k-kuRi” (ஆடிக் குறி):-
There are 4 indicators of this of which any one or none could occur in the month of Aadi in a year. In 2016 season, one Aadi-k-kuRi is going to occur. If Rohini is the star of the day on Dasami (10th thithi) or Ekadashi (11th thithi) in the waning period of the Moon (தேய்பிறை), one must observe the cloud formation. If they sky is cloudy or overcast, there will be good rains in the rest of the season of rainfall. This conjunction of Rohini and waning Dasami and Ekadasi is going to occur on 29th July 2016 from the sunrise of 29th July till the sunrise next day. We have to watch the cloud formation on that day to know about the rainfall in the period later.
As this period (29th July 2016) comes within the fortnight-long impact period of the 3rd day of Garbottam which shows more than average rains, we can expect good cloud formation on that day.
(2) “Pari vesham” of Moon (பரி வேடம்).
This is the halo around moon. On the day of Full Moon of Aadi, one must observe for the halo around the Moon. At the start of the impact period of 3rd day of Garbottam, that is, on 19th July 2016, there is going to be Full Moon. One must observe the Full Moon for the whole night on that day.
If there is halo (Parivesham) around the Moon in the first 4 hours of after Moon rise, there would be good rains in the month of Aippasi (NE monsoon period).
If the halo is seen in the second 4 hours of Moon at night, there will be good rains in the month of Karthigai (NE Monsoon).
In the third 4 hours if the halo is seen, there will be rains in the month of Margazhi.
In 2016, Full Moon will be there for the first 8 hours of night. After that Prathamai comes. Therefore the rains, if they materialise can be there only upto Karthigai, if Parisvesham is noticed.
Moreover if it rains on the first thithi after a Full moon or New Moon, it will rain till the time Moon comes to the same position (one month). This year rains were there in coastal Tamilnadu in November- December, as it rained on the 1st thithi (Prathamai) after 25th November (Karthigai Deepam) .
19th July of 2016 being a Full Moon day in the month of Aadi, cloud formation is needed on that day for good rainfall later. Suppose could formation happens on that day and it rains in the next day, there will be rains for one full month after that. (From 20th July to 18th August). Thus 20th July also must be watched for good rains thereafter.
This kind of rules in astrology shows that successive or periodical updates must be done for rainfall prediction.
On the basis of 3rd day of Garbottam which had good wind and cloud conditions, there is a good probability that the impact period having 19th July (Full Moon of Aadi) and 29th July (conjunction of waning Dasami and Rohini or Aadi-k-kuRi) is showing positive features for good North East Monsoon for Tamilnadu in 2016.
PS:- I will again post these and other dates of importance just before the date of observation.