Saturday, December 29, 2012

Rainfall prediction – Part 1 (Pre-rainy season observation & GarbOttam)

This is a series on astrological inputs on predicting rainfall in advance. I will write the articles in such a way that any interested amateur meteorologist can make the recordings, interface with meteorological maps and check whether the predictions do take place. I suggest that this methodology must be recorded for atleast 5 years continuously to derive a reliable set of factors for rainfall prediction. If anyone is doing this seriously, I request them to intimate me the findings.


Rainfall prediction is considered as Purva Chitti – prior wisdom, by Vedic Thought. In the ritualistic question and answer dialogue in the course of Ashvamedha yajna, one question is
"Who is called poorvachitti?"
The reply that follows is:- 
"The rain falling is called poorva chitti".

It is because the rain falling in a place is formed very much in advance under certain conditions, knowing which one can tell in advance whether it would rain or not. Reiterating this Varahamihira says,

"The predictions of an astronomer who pays exclusive attention, both day and night to the indications of rain afforded by pregnant clouds, will as little fail of success as the words of rishis.

What science can probably excel, in interest, the science relating to the prediction of rain, by a thorough study of which one though ignorant in other matters passes for a great astrologer in this Kaliyuga." (Brihad samhita, Chapter 21 – verses 3 &4)

The authors for rainfall prediction techniques.
Sages  Garga, Parasara, Kasyapa, Vatsa and others.

Books :- Brihad Samhita (Chapter 21 to 28) and Prasna Marga (Chapter 25)

Things needed:-
  • Knowledge of names of Lunar months and dates (thithi) and names of 27 stars of the Vedic astrology.
  • Astrology software or any source which will help one to know the star in which Sun or Moon transits on a particular day.
  • Round the clock observation or observation of the outside at regular intervals.
Period of observation.
From the Lunar month of Karthika until Shravana.

When to begin observation.
There are 3 dates given, two by Brihad Samhita and one by Prasna Marga. No explanation is given by the authors for the differences. My interpretation is given in brackets.
1.      The first day of the bright half of the lunar month of Karthika (Oct- Nov) – Siddhasena School (Check for the breaking of South West Monsoon in Lakshadweep or Kerala.)
2.      The day Moon transits Puravashada in the bright half of Margashira (Nov- Dec) – Sage Garga (Check for the first rains in Middle or North India)
3.      The day Sun enters the star Purvashada. This is occurs after 13-20 degrees in the Sign Sagittarius. The period of 14 days starting from this is called the period of 'Conception of rainfall' or GarbhOttam.
Importance of GarbhOttam.

The 14 day duration is the period taken by the Sun to transit the entire extent of Purvashada. The extent  of a star is 13 degrees and 20 minutes. Sun covers roughly 1 degree per day. GarbhOttam period is the period of Sun in the entire extent of Purvashada.
Preliminary observation for the 14 day period of GarbhOttam is to check  if the entire sky is covered with dark clouds and the Sun is hidden behind the clouds.

The observation (or any observation that is being said in this article) is applicable for the place of the observer. In olden days every village had astrologers doing that observation. Today meteorology applies to vast regions, but the ancient Indian method helps to tell on a day to day basis whether a particular locality would get rains or not. For that, the observer must be available on the place continuously atleast from Margashira to Phalguni and on specific days at other months.

 If on the 1st day of GarbhOtta, there are dark clouds all over the sky and sun is hidden behind, it will rain here and there and every now and then in the 14 day period when Sun will be transiting Arudra (in Gemini)

Similarly if on the 2nd  day of GarbhOtta, there are dark clouds all over the sky and sun is hidden behind, it will rain here and there and every now and then in the 14 day period when Sun will be transiting Punarvasu star (in Gemini and Cancer).

Similarly on the 3rd  day of GarbhOtta, there are dark clouds all over the sky and sun is hidden behind, it will rain here and there and every now and then in the 14 day period when Sun will be transiting Pushya star (in Cancer).

Like this Sun's transit upto Moola star (prior to starting of the GarbhOtta) is noted for rainfall. 

The rationale is that  each day of the GarbhOtta in Purvashada in Sagittarius will have bearing for the duration of sun's stay in every star starting from Arudra in the month of Aani (in tamil) / Gemini / lunar month of Jyeshta in the next year and goes upto Moola in next Margashira.

The stars mentioned below indicate the 14 day transit of Sun in that star. Eg 1st day of GarbhOtta will have an effect on 14 days of sun's transit in Arudra.

1st day – Arudra
2nd day – Punarvasu
3rd day – Pushya
4th day – Aslesha (Ayilyam)
5th day – Magam
6th day – Purva phalguni (Pooram)
7th day – Uttara Phalguni (Uttaram)
8th day – Hastha
9th day – Chithra
10th day – Swati
11th day – Vishaka
12th day – Anuradha (Anusham)
13th day – Jyeshta (Kettai)
14th day  - Moola.

If the sky is completely overcast for the whole day in one of these days, predict rainfall from the day Sun enters the corresponding star.
This year GarbhOtta started yester day (28-12-2012). The whole of yesterday, the sky was overcast in Chennai, at my place where I did the observation, right from the morning and it rained after midnight. Rains will mar the subsequent rains after 195 days. Therefore the first level of prediction is that there will be scattered rainfall in my place for 7 days as soon as Sun enters Arudra. Sun enters Arudra on the early morning hours of 22nd June 2013. Since for the whole day the sky was overcast, it is predicted that the first half of Arudra (7 days) would give rains. Since it rained in the night yesterday, we can expect a less wet or dry period in the 2nd half of the 14 day period starting from 22nd June. Cloud cover is good, but rains are not good during GarbhOtta days. It could be a drizzle but not rains.

The cloud cover continues today also. Therefore we can expect good rains once again after Sun enters Punarvasu star (After July 6th).  
Whether there will be good rains or not can be assessed from the following factors.

Basics factors to observe:-
1.      Winds
2.      Rain
3.      Lightening
4.      Roar of thunder
5.      Appearance of clouds

Now the next step:-

In all these 14 days, the above mentioned 5 points must also be observed. Then the observation must be continued everyday for four months until lunar month of Phalguni is over. If any single day has all the 5 factors present, good rainfall must be predicted on the 195th day from the day of observation.

In other words, one must note the thithi and paksha of the day of observation. Eg: Observation is on Dwitheeya in the dark half of Margshira. Its resultant rainfall will be on Dwitheeya on the bright half of Jyeshta. That is 6 and a half month from the month of observation.
If noticed in a thithi in the Bright half of moon, the result will take place on the same thithi on the dark half of moon 6 months later.
If noticed in the morning, the resultant rain will be in the evening on that day.

If winds or clouds are noticed in a direction, the resultant rain will be in the opposite direction on that day. Keeping this in mind one must record not only the features but also the direction and time of the day.

Now the features to be observed:-

Note:- Applicable on day to day basis. The prediction is for the corresponding day later, on the 195th day..

1.      Winds:-
Gentle and agreeable wind = Good rainfall
Cool breeze from North and Northeast = good rainfall.
Heavy winds = rain clouds would gather but be shattered
Dust storm = No rains
2.      Rain
In Margashira, there will be no rains. If it rains heavily, rainfall on the corresponding day would be affected. A gentle rain or drizzle would give good rainfall on the corresponding day after 6 and a half months.
3.      Lightening
Lightening = good rainfall
Rainbow in the morning or evening = good rainfall
4.      Roar of thunder
Low, rumbling roar of thunder = good rainfall
Heavy sounding thunder = rain clouds would shatter away.
5.      Clouds
Sky overcast with huge, bright, dense clouds = good rainfall
Needle shaped clouds or sword shaped clouds = good rainfall
Blood red clouds = good rainfall.

If one any day in the months from  Margashira to Phalguni, all the above 5 factors are present, the quantity of the subsequent rainfall will be 1 Drona. (Drona is equal to 200 phalas. Quantification in today's terms is not known. Perhaps the rainfall on those days can be recorded and cross checked with other days when similar conditions prevailed.)

Reduce the quantity by quarter for the absence of every one factor.

Three-some observation.
1.      Terrestrial
2.      Atmospheric
3.      Planetary.

(I) Terrestrial factors to be observed.
1.      Sweet chirpings of birds.
2.      Animals moving relaxedly and making pleasant sounds
3.      Kids making sweet sounds and playing
4.      Trees with sprouts
5.    Trees grow without diseases.

(II) Atmospheric factors to be observed.
1.      Clouds resembling pearl or silver colour
2.      Clouds in the shape of aquatic animal, huge and dense.
3.      These clouds scorched by bright sun light
4.      Gentle breeze (presence of 3 and 4 together would result in torrential rain on the 195th day)
5.      Sun and the Moon encircled by glossy, bright and thick halo.
6.      Sky filled with bulky clouds or smooth needle like clouds (cirrus), or in the shape of sword.
7.      Clouds appearing in red or blue tint.
8.      Pleasant twilights in morning and evening.
9.      Light rumbling thunder
10.  Rainbow in the lower horizon.
11.  Red glow in the horizon at dawn and sun set. This must be seen only in Margashira and Pushya months. (Solar months also)
12.  Clouds with halos

Month-wise observation

In Margashira –
·         red sun in the morning and evening, 
 -    sky in red colour before sunrise and after sunset.
·         clouds surrounded by halos,
·         very cold.
In Pushya -
  • ·         red sun in the morning and evening,
  • ·         clouds surrounded by halos,
  • ·          excessive snowfall.

In Magha –
·         strong wind,
·         sun and moon must be dimmed by clouds or snowfall at sun rise and sun set,
·         fog, mist, excessive cold
In Phalguna –
  • ·         rough and violent storms
  • ·       tawny colour of the sun,
  • ·         broken and imperfect halos around the sun and the moon,
  • ·         glossy clouds moving across the sky

The above ensure good 'conception of rainfall'.

In Chaitra and Vaishaka, sky marked by winds, clouds and halos ensure conception of rainfall which will fall 195th day afterwards. 

The following features in the 4 months from Margashira to Phalguni mar conception of rainfall.
1.      Meteor showers.
2.      Thunderbolt
3.      Dust storm
4.      Appearance of city-like formation of clouds.
5.      Unnatural phenomenon in the atmosphere in colour of sky, clouds etc and at sun rise and sun set.
6.      Rainfall
7.      Sighting of comets
8.      Eclipses
9.      Spots in solar disc (sun spot maxima?)

(III) Planetary factors to be observed in the 4 month period.

Good for conception of rainfall
 - Planets appearing with clear and bright disc at night
-  Planets moving in Northern declinations
- Moon and stars must appear white 

Planetary features marring conception of rainfall.

·         Eclipses ( mar rainfall later on the corresponding day)
·         Planetary war (where planets are close together in such a way one planet will be crossing another.) (mars rainfall for several days in the corresponding period.)

Position of Moon during the above 4  month period.

When the above 3-some favourable features of conception are present in a day when Moon is crossing Purvashada, Uttarashada, Purva bhadrapada, Uttarabhadrapada and Rohini, the subsequent rainfall on the 195th day will be abundant.

When the above 3-some favourable features of conception are present in a day when Moon is crossing Arudra, Aslesha, Magha , Swati and Satabhishak, the subsequent rains will go on for many days. On the contrary, if the 3 some factors are marred, there will be dryness.

If Moon crosses all the above mentioned stars with 3-some factors being present and marring factors being absent in Margashira - would give rainfall for 8 days later (after 195 days).

In Pushya - for 6 days
In Magha -16 days
In Phalguni – 24 days
In Chaitra – 20 days
In Vaishaka – 3 days.

(To be continued)

Related articles:-

Part 2:-

Part 3:-


Anonymous said...

NASA news

sun winked at them on 22.12.2012
solar spot maxima

Jayasree Saranathan said...

Please send the link.

tenali said...

this is the link

Unknown said...

The amazing solar 'wink' that let us know the end of the world really was just a misconception
Eruptions of magnetic activity on the solar surface appear to make the sun 'wink' as the time many believed the world would end passed
Comes after Nasa was forced to issue two videos explaining the Maya prophecies were a misconception

Read more:
Follow us: @MailOnline on Twitter | DailyMail on Facebook

Anonymous said...

கர்ப்போட்டம் பற்றி தமிழில் எனக்கு தேவை ;[ எனக்கு ஆங்கிலம் தெரியாது ]

Anonymous said...

Jayasree Mam,

Do we need to have a good command over Astrology too to keep watch on climatic changes?

- Krishna

Jayasree Saranathan said...

Thanks for the link Mr Tenali and Mr Haran.

The Solar flares happen regularly. Its to add some pep in reporting they had mentioned Mayan prophecy. Everytime Sun crosses Fiery signs (Aries, Leo, Sagittarius / corresponding Tmnil months are Chithrai, Avani and Margazi) this happens. When it crosses, Aries, the intensity will be more as Aries is Martian sign (Mars is a fiery planet as per astrology).

When Mars and Sun join in any of these signs, the intensity will be more and have the potential to disrupt communication equipments and satellites besides affecting human behaviour. My older articles on this can be read here:-

On 22nd December, Sun was in Sagittarius (fiery sign) but Mars had moved out. If Mars had joined the sun in close degrees in Sagittarius, perhaps scientists would have detected it earlier and geared for protecting the instruments.

On the rainfall prediction, this is a matter of concern. We have to check past records of sun spot / solar flare occurring in the Garbhotta period (plus 4 months till Phalguni) with the rainfall in the corresponding rainy season, to get a better insight into its marring effect on garbhottam.

Jayasree Saranathan said...

//கர்ப்போட்டம் பற்றி தமிழில் எனக்கு தேவை ;[ எனக்கு ஆங்கிலம் தெரியாது ]//

As of now I am busy with other works and not in a position to translate this. If any reader is willing to translate, I would post it here.

Jayasree Saranathan said...

@ Mr Krishna,

I have mentioned things needed at the beginning. That much knowledge of names and positions of planets are enough.

Srinivasan Ramakrishnan said...

ஹலோ மேடம்,
இந்த கட்டுரைஐ தமிழில் வெளிட்டால் நன்றாக இருக்கும்.

Brihad Samhita or Brihad Jathaka both are same?

Jayasree Saranathan said...

//இந்த கட்டுரைஐ தமிழில் வெளிட்டால் நன்றாக இருக்கும்.//

I hope to get it translated in a day or two. Once it is ready, I will post it.

//Brihad Samhita or Brihad Jathaka both are same?//

No they are not the same. Usually a Samhita will be a compilation or a collection. Brihad samhita is a miscellaneous collection of astrological issues. In Brihad samhita you will come across mundane and worldly issues. On the contrary, Brihad Jathaka is Phalitha part (predictive part) of astrology. It deals with horoscopy of individuals.

Jayasree Saranathan said...

From: Arun Upadhyay
Date: Sun, Dec 30, 2012 at 5:45 PM
Subject: Re: Non-random-Thoughts:Rainfall prediction – Part 1
To: jayasree

Excellent article. It will take some time to grasp it-full logic may not be understood.
I have an excellent compilation in sanskrit and hindi on rainfall. You may see the English introduction by Mr. A S Ramnathan in Kadambini.

Jayasree Saranathan said...

Meteor shower on the morning of 3rd (Thursday - today). Meteor shower Quadrantids come from the direction of Big Dipper, it means it will be visible / experienced in the Northern hemisphere. Meteor shower has a marring effect on Garbhottam (conception of rainfall today). We have to keep this mind while watching rainfall on the corresponding period.

This day being the 6th - 7th day of Garbhottam, the corresponding period comes in Shravana - Bhadarapada (Tamil month Avani) which is the first month of the rainy season.

ASHISH said...

Pls ref following in your article :

"14 day transit of Sun in that star

If the sky is completely overcast for the whole day in one of these days, predict rainfall from the day Sun enters the corresponding star. "

If the overcast sky was to be noted when Sun entered in Hashta Nakshatra, how do we predict for earlier transits viz Arudra to Uttaram since Sun transits Purvashada after Moola and completes the transit at Mrigashiras prior to Arudra.

My comprehension in all possibility is incorrect. However one needs to observe Sun’s transit from Arudra to Moola as per your comment regarding 'Conception of rainfall' or GarbhOttam.

Jayasree Saranathan said...

Dear Mr Asshish,

That is not correct. I have given a time period in this article. I said watch the sky for certain indicators for full 4 months from Margashira and Phalguni. For Chaitra and Vaishaka, the factors are different and I have noted them.

After that the observations will be different. I will write them in due course. From the time of Sun's entry into Arudra, different factors must be observed - one among them being planetary positions which I had mentioned in El Nino article.

You would have observed that there is not much on planetary positions in Garbhottam period. They come from Jyeshta month onwards. What I have written here is upto Vaishaka month. In this period atmospheric conditions are important.

Jayasree Saranathan said...

@ Ashish,

The theme of this article is watch the 14 day period of Garbhottam when Sun transits Purvashada in the month of Margashira. Each day corresponds to each star starting from Arudra which goes upto Moola which is the 14th star from Arudra.

Factors observed on each day in Garbhottam period, will manifest as rainfall or lack of the same, during Sun's transit (14 days) in the corresponding star starting from Arudra.

Hope this is understood.

Jayasree Saranathan said...

//ஹலோ மேடம்,
இந்த கட்டுரை தமிழில் வெளிட்டால் நன்றாக இருக்கும்//

The Tamil version of this article has been published. Read and circulate.

Jayasree Saranathan said...

Part-2 of the article has been posted.

Jayasree Saranathan said...

Part 4 of rainfall astrology is posted

Follow the same in Tamil at

Readers are free to share these with due acknowledgements.

Knowledge Seeker said...

In 2016 the moon won't be there in Purvashada during bright half. Should we consider dark half also? With tropical ayanamsha, moon changes to Purvashada on 27-12-2016 at 2:35:07 PM having Margashira Krishna Chaturdashi. Can this be considered as starting point?

Jayasree Saranathan said...

@ Mr Hemanth Kumar,

The starting point is Sun's transit in Purvashada star, not moon. Tomorrow early morning this transit of Sun begins. If you are interested, please read this article of last year's garbottam:-
Read the articles under the tag "Rainfall 2016" to know how I had done the observations and inferences.

For 2017 rainfall, I have started the series of articles

You can read the first 2 levels of prediction in the above link. The 3rd level is Sun's transit in Purvashada that is to begin tomorrow. I will be posting soon the article on this. Please stay in touch.

Knowledge Seeker said...

Thank you. I have read all these articles. Appreciate your efforts and blogging style. By the way, my question was about the 2nd point of the highlighted section "When to begin observation" in this article.

Jayasree Saranathan said...

Ok Mr Hemanth Kumar. Noted. In Margashira, whatever it could be -lunar or soalr month- Amavasya comes generally in Jyeshta or Moola. So Moon in Purvashada would be in bright half. Please check the date you have given. On 27-12-2016 Moon was in Jyeshta not Purvashada.

Knowledge Seeker said...

Namaste, Since this is related to Physical Astronomical observations, I used Tropical (Sayana) Ayanamsha in JHora software which gives Moon's position in Purvashada-1 (13 Sg 20'00.04"). JHora uses astronomical database supplied by Swiss Ephemeris, the latter being based on NASA's JPL datasets, which are most reliable data of modern physical astronomy. A simplified software of Swiss Ephemeris can be freely downloaded by anyone, which shows half a minute errors. Hence JHora is reliable as far as physical planetary positions are concerned. Your observation is right with respect to other Ayanamsha's like SSS, Lahiri, etc., in Nirayana mode. Thank you.

Jayasree Saranathan said...

@ Mr Hemanth Kumar,

Vedic astrology follows sidreal positions. If you check the 3 models given in the article, the first is thithi based and the last two are star based. Tropical astrology is not applicable to and is useless for Vedic astrology. If you have read my posts on Greek vs Vedic astrology, the main issue was this - tropical or sidreal only. Mr Dieter Koch who has given Swiss ephemeris kept insisting on Tropical astrology. But if you follow that you would end up celebrating Deepavali in Purattasi month and Navaratri in AavaNi month!

If you want to do rainfall predictions, follow sidreal position of Sun, moon and planets. You would find that the yogas et al were with reference to star positions only.

Marthi SivaRama YajnaNarayana Sarma said...


Do you think this same method of analysis is applicable for all countries like USA, Russia, Australia..? If not how can not Garbottam and predict rainfall in those regions?

Jayasree Saranathan said...

This method is applicable only for the Indian sub continent.
For other places, people of those places have to observe and work out models for them as the sages had done for our country through generations of observation.

Marthi SivaRama YajnaNarayana Sarma said...

@Jayasree Saranathan

Thank you

Unknown said...

Please write a book for the benefit of all astrologers as your immense research and knowledge will benefit us and preserve your invaluable knowledge . Sunil Dutt