Brihat Samhita
वर्षाकाले वृष्टिं करोति सद्यः शिरीषपुष्पऽभः । शिखिपत्रनिभः सलिलं न करोति द्वादशाब्दानि ॥ ३-२८ ॥
If in Varṣā the colour of the sun be that of the flower Śirīṣa (Mimosa flexuosa) there will be immediate rain; if the colour be that of the peacock’s plume there will be no rain for twelve years to come.
english translation
varSAkAle vRSTiM karoti sadyaH zirISapuSpa'bhaH । zikhipatranibhaH salilaM na karoti dvAdazAbdAni ॥ 3-28 ॥
hk transliteration by Sanscript