Brihat Samhita
वर्णेनएकेन यदा बहुलः स्निग्धः क्षुराभ्रकऽकीर्णः । स्वऋतौ सद्यो वर्षं करोति पीतश्च दीप्तार्कः ॥ ३४-०७ ॥
If in the rainy season, the solar or lunar halo should either appear of a single colour, or glossy; if of different colors, or occupied by clouds sword-like in shape, or if the sun, while surrounded by a halo, should appear very bright and yellow, there will be immediate rain.
english translation
varNenaekena yadA bahulaH snigdhaH kSurAbhraka'kIrNaH । svaRtau sadyo varSaM karoti pItazca dIptArkaH ॥ 34-07 ॥
hk transliteration by Sanscript