GOES-13 10.7 µm IR images

Hurricane Igor became the 4th hurricane of the season in the Atlantic Basin late in the day on 11 September 2010. GOES-13 10.7 µm IR images from the CIMSS Tropical Cyclones site (above) displayed an increasingly organized structure to the convection surrounding the center of the storm. Igor existed in an environment of low deep layer wind shear, which was a favorable factor for further intensification.

The development of a few convective bursts near the center of Igor’s circulation could be seen on GOES-13 0.63 µm visible images (below), suggesting the formation of an eyewall.

GOES-13 0.63 µm visible images

A 22:56 UTC microwave image from the SSMI/S instrument (below) revealed a well-defined convective ring around the center of Igor.

SSMI/S 85 GHz mircrowave brightness temperature

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GOES-11 / GOES-15 / GOES-13 3.9 µm shortwave IR images

A large natural gas explosion occurred in San Bruno, California on the evening of 09 September 2010, which killed 4 people and destroyed 38 homes. McIDAS images of GOES-11 (GOES-West), GOES-15, and GOES-13 (GOES-East) 3.9 µm shortwave IR channel data (above) showed the resulting fire “hot spots” (black to yellow color enhancement) during the 01:00 UTC to 04:00 UTC time period (6 pm to 9 pm local time).

The plot below shows that the maximum 3.9 µm shortwave IR pixel brightness temperatures were seen on the 01:15 UTC (6:15 pm local time) GOES-15 and GOES-13 images, and 30 minutes later at 01:45 UTC (6:45 pm local time) on the GOES-11 images.

Plot of GOES-11, GOES-15, and GOES-13 3.9 µm IR brightness temperatures

A comparison of the 1-km resolution NOAA-16 AVHRR 3.7 µm and the 4-km resolution GOES-11 3.9 µm shortwave IR images (below) showed the fire hot spot (black pixels) around 02:00 UTC (7:00 pm local time). Note the more accurate placement of the fire hot spot on the AVHRR image — San Bruno is located more toward the eastern side of the San Francisco Peninsula.

NOAA-16 AVHRR 3.7 µm shortwave IR and GOES-11 3.9 µm shortwave IR images

AWIPS images of the 1-km resolution MODIS 3.7 µm shortwave IR channel and the 4-km resolution GOES-11 3.9 µm shortwave IR data around 06:00 UTC (11:00 pm local time) can be seen below. Although no fire hot spot was evident on the GOES-11 image, a small cluster of yellow pixels could still be seen on the MODIS image.

MODIS 3.7 µm shortwave IR and GOES-11 3.9 µm shortwave IR images

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MODIS 6.7 µm water vapor image + GOES-13 6.5 µm water vapor image

AWIPS images of the 1-km resolution MODIS 6.7 µm water vapor channel and the 4-km resolution GOES-13 water vapor channel data on 09 September 2010 (above) is another great example that demonstrates how an improvement in spatial resolution leads to a dramatic improvement in the ability to detect the total areal coverage of mountain wave signatures on water vapor imagery.

Overlays of RUC model wind speeds (below) indicated that a 105-knot upper level jet was located over the region — these strong winds were interacting with the complex terrain of the Rocky Mountains to produce the widespread mountain waves.

MODIS water vapor image + RUC model wind speeds

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MODIS fog/stratus product + GOES-11 fog/stratus product

AWIPS images of the 1-km resolution MODIS fog/stratus product and the 4-km resolution GOES-11 fog/stratus product (above) revealed the presence of fog and stratus clouds that extended fairly far inland across much of southern California around 06 UTC on 08 September 2010 (11 pm local time on 07 September). The improvement in spatial resolution on the MODIS image allowed a more accurate assessment of the location of the stratus cloud edges, as well as the location of the cloud holes immediately offshore.

McIDAS images of the GOES-15 0.63 µm visible channel data (below) showed how persistent this deck of stratus clouds was during the daytime hours. In fact, these clouds held down temperatures such that the daily high temperature was only 68º F at Burbank (station identifier KBUR, located near the center of the images) — their normal high temperature for the date is 88º F, and they had a high temperature of 102º F just 4 days earlier.

GOES-15 0.63 µm visible channel images

10-km resolution GOES-11 sounder Cloud Top Height product images (below) showed that there was a high amount of variability in the heights of these stratus cloud tops (which was also evident in the appearance of the stratus cloud deck on the GOES-15 visible imagery above).

GOES-11 sounder Cloud Top Height product

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