CALIFORNIA- An advanced U.S. weather satellite has been launched into polar orbit from California. It has been designed to improve the accuracy of extended forecasts.

The Joint Polar Satellite System-1 lifted off from Vandenberg Air Force Base at 1:47 a.m. Saturday on a United Launch Alliance Delta 2 rocket.

The satellite is the very first of four next-generation spacecraft for NASA and the National Oceanic and Atmospheric Administration.

JPSS-1 carries a suite of five instruments intended to make global observations that will improve forecasts of severe weather events three to seven days beforehand. It will circle the Earth from pole to pole 14 times a day.

The satellite also will contribute to near-term weather forecasts, as well as climate and ocean dynamics research.