GOES-11 10.7µm InfraRed (IR) images (above; Java animation) showed an area of strong thunderstorms (exhibiting cold brightness temperatures of -70 to -80º C, black to white enhancement) expanding eastward toward the islands of American Samoa in the South Pacific Ocean on 28-29 May 2007. The motion of these storms on satellite imagery prompted the issuance of a Flash Flood Warning for the islands of Tutuila, Aunuu, and Manua at 02:54 UTC on 29 May (3:54 PM on 28 May, local time). It is important to note that there is no radar in that particular region, making satellite imagery the only forecasting tool for such hazards — however, GOES-11 Southern Hemisphere sector imagery (below) is only available over that region 2-3 times per hour.

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The moon was observed adjacent to the Earth’s limb on the GOES-12 imagery at 11:15 UTC on 24 May 2007. Some of the large-scale features of the moon’s surface could be seen in the GOES-12 visible channel image (above), while the other 4 InfraRed (IR) channels (below) revealed a “banded” pattern of brightness temperatures resulting from the large thermal gradient between the very hot sunlit portion of the moon (where temperatures can reach +110º C / +230º F) and the very cold “dark” side of the moon (where temperatures can fall to -180º C / -292º F).

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An AWIPS image of MODIS sea surface temperature (SST) on 21 May 2007 (above) shows an intricate pattern of Atlantic Ocean eddies along either side of the axis of the Gulf Stream. SST values in the 70-78º F / 21-26º C range (orange enhancement) marked the Gulf Stream axis as it meandered northeastward across the western Atlantic. Some of the eddies were offset a considerable distance from the Gulf Stream axis, most notably the pronounced cool eddy (SST values around 64º F / 18º C, dark green enhancement) located well to the southeast. The black areas over water on the image are regions where the MODIS cloud mask product indicated that clouds were present — no SST data is generated for such “cloudy” pixels. Although some cloud patches were indeed present, the strong thermal gradients associated with the Gulf Stream sometimes cause the MODIS cloud mask product to falsely indicate “cloud” over fairly large regions that in reality are not cloudy.

Note how the Real-Time Global SST model analysis (below) does a poor job resolving the details of these particular eddy features.

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The largest wildfire in Georgia history started on 16 April, and continued to burn on 20 May and 21 May 2007. The Terra and Aqua false-color red/green/blue (RGB) images using MODIS channels 07, 02, and 01 (above) reveal the extensive burn scars resulting from the 472,000 acre Sweat Farm Road / Big Turnaround fire south of Waycross, Georgia (station identifier KAYS), as well as the 125,000 acre Bugaboo fire that straddled the Georgia/Florida border. The locations of the hottest active fires were indicated by the pink-colored pixels along the periphery of the burn scars.

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