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UPDATE: Nov. 15,About 2017, 9:05 a.m. EST The JPSS launch on Wednesday morning was scrubbed due to strong upper level winds. United Launch Alliance, which operates the rocket taking the satellite to space, said it is searching for a new launch opportunity.

After billions of dollars in cost overruns and delays, NASA is planning to launch one of the most important weather satellites ever early Wednesday morning.

The Joint Polar Satellite System-1, or JPSS-1, satellite -- which will be invaluable for improving forecasting, detecting lost sailors, aiding firefighters, and other applications -- is expected to blast off from Vandenberg Air Force Base in California at 1:47 a.m. PT, or 4:47 a.m. ET, aboard a United Launch Alliance Delta II rocket. The JPSS-1 launch to Wednesday after the launch, originally planned for Tuesday was halted.

The JPSS-1 is the first in the National Oceanic and Atmospheric Administration's (NOAA) next-generation of four polar-orbiting satellites that provide the majority of data streamed into weather forecasting models.

In its orbit, the satellite will pass over the equator about 14 times per day, and cover the globe twice every 24 hours. Sensors aboard the spacecraft will collect measurements of air, ocean, and ground conditions, as well as fire locations, temperatures and water vapor throughout the atmosphere.

The National Weather Service anticipates being able to take advantage of these measurements to improve its forecasts, particularly for high-impact weather events, such as hurricanes and winter storms. Instruments aboard polar-orbiting satellites, like ones aboard JPSS-1 and its preceding spacecraft, known as the Suomi-NPP, obtain data on the winds and moisture in the upper atmosphere.

This information supplements the data gathered from weather balloons launched at sites across the U.S., particularly for large expanses of water where balloon launches are not feasible.

Polar-orbiting satellites also keep tabs on erupting volcanoes and receive the emergency pings from planes and mariners in distress, which are then used to dispatch rescue crews.

Satellites like JPSS-1 are not responsible for the images typically shown on your nightly weather forecast or your phone's weather app, since most weather imagery comes from geostationary satellites, which orbit above a fixed point on the planet.

For years, policy makers and scientists worried about a looming polar-orbiting satellite gap that could come once one satellite blinked out from old age, prior to the next one launching.

Assuming that JPSS-1 launches successfully on Wednesday and functions normally in orbit, the U.S. will again have two working polar satellites at work at the same time. This would avoid a dreaded gap that could have adversely affected weather forecast accuracy in the U.S.

“Eighty-five percent of the data flowing into our weather forecast models come from polar-orbiting satellites, such as Suomi NPP and the new JPSS series," Louis W. Uccellini, director of the National Weather Service, said in a statement.

The new satellite will be the most advanced polar-orbiting weather platform the U.S. has yet put to use, NOAA officials said, since it will carry upgraded instruments able to gather more weather information than ever before.

UPDATE: Nov. 14, 2017, 8:20 a.m. EST This story was updated to reflect a new launch date set for Wednesday after a scrubbed launch on Tuesday.