Digital Goa, May 18- IMD Goa has issued an orange alert for Goa from May 20 to 22, warning of very heavy rainfall, thunderstorms, and strong winds up to 60 kmph in both North and South Goa districts. A yellow alert is in place for May 18, 19, 23, and 24, with moderate rain and wind gusts of 30–40 kmph expected.