Farewell, NOAA-18

By Douglas Schumacher • 6 June 2025

Today at 17:40 UTC, NOAA decommissioned one of its three remaining legacy polar-orbiting weather satellites, NOAA-18. The spacecraft was launched on May 20th, 2005, and was declared operational on August 30th, 2005. For nearly 20 years, NOAA-18 collected weather information across the whole globe, with every point on Earth in view, at minimum, every 12 hours.

The final NOAA-18 orbit collecting data over the continental United States occurred around 16:08 UTC today. At this point, the AVHRR visible/IR imaging sensor was no longer collecting infrared bands 4 and 5. The HRPT direct broadcast signal during this overpass was collected by SSEC’s X/L-band tracking antenna in Madison, and processed using EUMETSAT’s AAPP and CSPP Polar2Grid software:

Band 1: “Red Visible” [0.63 µm]	Band 2: “Vegetation Near-IR” [0.86 µm]	Band 3A: “Snow/Ice Near-IR” [1.61 µm]

Of NOAA’s 5th generation POES spacecraft, 2 remain active: NOAA-15 and NOAA-19. Both are expected to be decommissioned later this summer. Prior to today, the last NOAA polar weather satellite to be decommissioned was NOAA-16 on June 9th, 2014. The JPSS constellation (S-NPP, NOAA-20, and NOAA-21) remains active as NOAA’s primary polar-orbiting weather satellites.

Categories: General interpretation, POES