Hail damage to Space Shuttle external fuel tanks

February 26th, 2007 |

GOES-12 10.7µm IR image

An isolated thunderstorm developed over east-central Florida and moved over the Kennedy Space Center during the late afternoon on 26 February 2007, producing golf ball size hail (2.0 inches in diameter) and wind gusts as high as 72 mph (SPC storm reports). This hail produced damage to the external fuel tanks of the Space Shuttle Atlantis, which was on the launch pad undergoing preparations for a 15 March 2007 launch. This particular convective cell was relatively compact and formed rather quickly, and exhibited cloud top temperatures between -50 to -60º C (orange to red enhancement) on GOES-12 10.7µm InfraRed (IR) imagery (above; Java animation).

A comparison of 4-km resolution GOES-12 IR imagery with the corresponding 1-km resolution NOAA-15 AVHRR IR image (below) shows that more accurate (and significantly colder) cloud top temperatures can be detected using satellite instruments with better spatial resolution. Note the distinct “overshooting top” region with a minimum brightness temperature of -65º C (dark red enhancement) on the 21:50 UTC NOAA-15 image, versus cloud top temperature values that were only as cold as -54º C (orange enhancement) on the 21:45 UTC GOES-12 image (these two IR images were about 20-25 minutes prior to the time of the reported hail damage). The Advanced Baseline Imager (ABI) instrument on GOES-R (scheduled for launch in 2014) will have IR channels with a spatial resolution of 2 km, which should improve cloud top temperature detection capabilities over the current GOES imager IR channels.
NOAA-15 / GOES-12 IR image comparison