GOES-15 0.63 µm visible images (Super Rapid Scan Operations)

As part of the GOES-15 Post Launch Science Test, the satellite was placed into Super Rapid Scan Operations (SRSO) mode on 13 September 2010, providing images as frequently as every 1 minute during the day. GOES-15 0.63 µm visible channel images (above; also available as a QuickTime movie) showed the well-defined eye of Hurricane Igor, with SRSO images during a 4 hour period (from 16:39 – 20:39 UTC). The visible images were brightened a bit after 19:26 UTC to help detect the presence of any mesoscale vortices within the eye.

A comparison of 1-minute interval GOES-15 SRSO images with the normal operational 15-minute interval GOES-13 visible images (below) clearly demonstrates the advantage of higher temporal resolution for monitoring the evolution of the eye structure of the hurricane (courtesy of Tim Schmit, NOAA/ASPB).

GOES-15 1-minute visible images (left) and GOES-13 15-minute visible images (right)

While Hurricane Igor maintained a Category 4 intensity for more than 24 hours, an SSMI/S 85 GHz microwave brightness temperature image from the CIMSS Tropical Cyclones site (below) suggested that the storm might be entering an eyewall replacement cycle (ERC) late in the day on 13 September, which would signal a likely decrease of the storm’s intensity during the ERC process.

SSMI/S 85 GHz microwave brightness temperature image

A large eye was also evident on GOES-13 10.7 µm IR imagery (below).

GOES-13 10.7 µm IR images

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SSMI/S 85 GHz microwave brightness temperature image

An SSMI/S 85 GHz microwave brightness temperature image from the CIMSS Tropical Cyclones site (above) displayed a well-defined eyewall structure associated with Hurricane Igor ar 11:32 UTC on 12 September 2010.

GOES-13 1-km resolution 0.63 µm visible channel images (below) showed an improving appearance to the eye of Igor during the morning hours.

GOES-13 0.63 µm visible channel images

========== UPDATE ==========

GOES-13 10.7 µm IR images

Igor rapidly intensified into a Category 4 hurricane later in the day. GOES-13 4-km resolution 10.7 µm IR images (above) displayed a well-defined eye, while a plot of the CIMSS Advanced Dvorak Technique (below) showed the trend of rapid intensification.

Plot of the CIMSS Advanced Dvorak Technique (ADT)

1-km resolution GOES-13 0.63 µm visible channel images (below) showed a fairly nice eye structure during the daytime hours.

GOES-13 0.63 µm visible channel images

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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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