Kauaʻi or Kauai is geologically the oldest of the main Hawaiian Islands. With an area of 562.3 square miles (1,456.4 km2), it is the fourth largest of the main islands in the Hawaiian archipelago, and the 21st largest island in the United States. Known also as the "Garden Isle", Kauaʻi lies 105 miles (169 km) across the Kauaʻi Channel, northwest of Oʻahu. This island is the site of Waimea Canyon State Park.
The United States Census Bureau defines Kauaʻi as Census Tracts 401 through 409 of Kauaʻi County, Hawaiʻi, which is all of the county except for the islands of Kaʻula, Lehua, and Niʻihau. The 2010 census population of Kauaʻi (the island) was 67,091, with the largest town by population being Kapaʻa.
Kauai’s climate is generally mild, although localized weather phenomena and infrequent storms have caused instances of extreme weather. At the lower elevations the annual precipitation varies from an average of about 50 inches on the windward (northwestern) shore, to less than 20 inches on the (southwestern) leeward side of the island. Average temperature ranges from 71 °F (22 °C) in February and March to 79 °F (26 °C) in August and September. Kauai’s mountainous regions offer cooler temperatures and provide a pleasant contrast to warmer coastal areas. At the Kōkeʻe state park (3200–4200 ft. ASL), day temperatures vary from an average of 45 °F (7 °C) in January to 68 °F (20 °C) in July. In the winter temperatures have been known to drop down to the 30s and 40s at Kōkeʻe state park, which holds an unofficial record low of 29 °F (-2 °C) recorded in February 1986 at Kanaloahuluhulu Meadow.
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