The 2021–22 South Pacific cyclone season was a near average tropical cyclone season within the South Pacific Ocean to the east of 160°E. The season officially started from November 1, 2021, and officially ended on April 30, 2022, however a tropical cyclone could form at any time between July 1, 2021, and June 30, 2022, and would count towards the season total. During the season, tropical cyclones will be officially monitored by the Fiji Meteorological Service, Australian Bureau of Meteorology and New Zealand's MetService. The United States Armed Forces through the Joint Typhoon Warning Center (JTWC) will also monitor the basin and issue unofficial warnings for American interests. The FMS attaches a number and an F suffix to tropical disturbances that form in or move into the basin while the JTWC designates significant tropical cyclones with a number and a P suffix. The BoM, FMS and MetService all use the Australian Tropical Cyclone Intensity Scale and estimate windspeeds over a period of ten minutes, while the JTWC estimated sustained winds over a 1-minute period, which are subsequently compared to the Saffir–Simpson hurricane wind scale (SSHWS).

Tropical Cyclone Ruby was a strong but short-lived tropical cyclone which impacted New Caledonia with strong winds and rainfall, after its predecessor tropical low and a nearby trough caused disruption over some parts of the Solomon Islands. The third named system of the 2021-22 Australian region cyclone season and the first cyclone of the 2021-22 South Pacific cyclone season, Ruby formed from an area of convection that was first monitored by the Joint Typhoon Warning Center (JTWC) on 8 December in the Solomon Sea. However, the system didn't officially become a tropical low until 06:00 UTC on 10 December, when the Australian Bureau of Meteorology (BoM) started to issue bulletins on it. After stalling over the area, the storm moved southeastwards over the Coral Sea, where it continued to develop under favorable conditions. The system was finally upgraded to Tropical Cyclone Ruby two days later as gale-force winds encircled its eastern portions.