Sapta-nādi-chakra is very useful in prediction of weather, esp of rainfall. There are two variants based on two ancient sources of Sapta-nādi-chakram :
Narapati-jaya-charyā and Krishi-Parāshara, and all later texts are based on them, such as Kadambini.
The original source of Sapta-nādi-chakra was a Tantric text 'Yāmaleeya-Svarodaya'.
Here, both variants of Sapta-nādi-chakra currently used by many traditional panchangas are being presented ('Nax' means Nakshatra) :
|Original (Ancient) Design :|
|Narapatijayacharyā's (~1000 AD) Design :|
Chandā-nādi represents fierce winds.
Vāyu-nādi is for more than normal winds.
Dahnā-nādi represents more temperature.
Saumyā-nādi represents normal conditions.
Neerā-nādi represents normal rains.
Jala-nādi represents more rains.
Amrit-nādi represents maximum rains.
Start from Krittikā (= number 3, numbering begins from Ashvini) in Chandā-nādi and assign nakshatras to nādis in the serpentine manner as shown in the tables above. Traditional texts present Sapta-nādi-chakra in a confusing manner , which makes it difficult to decide which of the two chakras is correct. Here, both have been presented in a well-ordered manner, which makes it easy to see that the left table is correct, because in it planets are placed according to their geocentric (or Merucentric) distances : Saturn-Jupiter-Mars-Sun-Venus-Mercury-Moon. In the right table, Jupiter and Sun are accorded lordship of wrong nādis.
Narapatijayacharyā can be procured from Chowkhambā Sanskrit Sansthān (Vārānasi). It gives some ancient rules for using this chakra.