For the past 20 years, from the beginning of November to the middle of April, two types of aircraft, the NOAA G-IV and the USAF Reserve WC-130J, have been flying over the Gulf of Mexico, along the U.S East Coast and even over the Pacific Ocean to gather data on winter storms that could have big impacts of wind, rain, freezing rain, sleet and snow and storm surge.
The number of aircraft in the NOAA and USAF Reserve Hurricane Hunter fleet
How do the crews know where and when to fly? Those orders come from NOAA’s National Centers for Environmental Prediction in College Park, Maryland. Depending upon where the winter storm could develop, the aircraft are sent to the Gulf of Mexico, or the Atlantic Ocean off the middle-Atlantic coastline, or perhaps both. They also fly over the Pacific Ocean between Hawaii and California for winter storms, including atmospheric rivers, that may affect the U.S West Coast. And just as is done for tropical cyclones, the missions are coordinated through the Chief, Aerial Reconnaissance Coordination All Hurricanes, also known as CARCAH, located at NOAA’s National Hurricane Center in Miami.
As with hurricane missions, the two aircraft obtain different but complementary data. The NOAA G-IV flies at high altitude (40,000 to 45,000 feet) and the USAF WC-130J does so at a lower altitude (24,000 and 30,000 feet). Just like those flights into tropical cyclones, the aircraft will deploy a series of dropwindsondes over the data-sparse oceanic regions, gathering data on temperature, wind, moisture and pressure.
The data from the aircraft is quality-controlled by CARCAH and goes into a number of computer models to help improve the forecast of the high-impact winter storms. It ensures the most accurate winter storm watches, warnings and advisories are issued to keep everyone safe.