POES AVHRR 10.8 µm IR images

AWIPS images of POES AVHRR 10.8 µm IR data (above) showed a thunderstorm that was moving off the Georgia/Florida coast during the pre-dawn hours on 17 June 2011. Rapidly-warming cloud top IR brightness temperatures indicated that this thunderstorm was quickly dying.

A POES AVHRR false color Red/Green/Blue (RGB) image at 12:36 UTC (below) depicted a well-defined outflow boundary resulting from the downdrafts of the collapsing thunderstorm — and to the east of the storm, the hazy signature of residual smoke from wildfires that had been burning across the region during previous days.

POES AVHRR false color Red/Green/Blue (RGB) image

McIDAS images of GOES-13 0.63 µm visible channel data (below) showed that a great deal of the smoke east of the storm was apparently dissipated by cleaner downdraft air from the dying convection.

GOES-13 0.63 µm visible channel images

This clearing of the smoke was also apparent on a MODIS true color image from the SSEC MODIS Today site (below).

MODIS true color image

For additional images and information, see the US Air Quality “Smog Blog”.

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FY-2E 0.73 µm visible channel images (click image to play animation)

The Nabro volcano erupted in the northeast Africa country of Eritrea on 12 June 2011. An oblique view using the Chinese FY-2E satellite (positioned over the Equator at 105º East longitude) 0.73 µm visible channel data (above; click image to play animation) showed the volcanic plume streaming northwestward on 13 June (the Nabro volcano is located near the bottom center of the images. Note that the plume became much brighter on the visible images later in the day, due to forward scattering.

A sequence of EUMETSAT Meteosat-9 7.35 µm “water vapor channel” images (below; click image to play animation) was useful for following the leading edge of the volcanic plume (the volcano summit is circled on the first few images of the animation). The plume moved northward over far northeastern Africa, and eventually curved anticyclonically and passed over the northern Arabian Peninsula on 14 June. It then appeared as if the leading edge of the volcanic plume might have eventually become entrained into a conveyor of isentropic ascent, where moisture began to increase (exhibiting a darker blue color on the water vapor images).

Meteosat-9 7.35 µm water vapor channel images (click image to play animation)

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GOES-12 0.63 µm visible channel images

Hurricane Adrian developed into a Category 3 hurricane early in the day on 09 June 2011. McIDAS images of GOES-12 0.63 µm visible channel data (above) initially showed a well-defined eye before it began to get partially obscured by the high clouds of a central dense overcast (CDO).

DMSP SSMIS 85 GHz microwave images from the CIMSS Tropical Cyclones site (below) revealed a distinct eye at 12:09 UTC and 14:56 UTC.

DMSP SSMIS 85 GHz microwave images

GOES 10.7 µm IR images (below) also briefly showed a well-defined eye early in the day, which later filled in a bit beneath the CDO as a curved band of cold high clouds began to wrap around the eastern and northern quadrants of the hurricane.

GOES 10.7 µm IR images

The circulation of Hurricane Adrian could be clearly seen on an AWIPS image of ASCAT scatterometer winds overlaid on a GOES IR image (below).

ASCAT scatterometer winds (overlaid on GOES IR image)

AWIPS images of the MIMIC Total Precipitable Water (TPW) product (below) showed that Adrian was tapping moisture from the Inter-Tropical Convergence Zone (ITCZ) / “Monsoon Trough”, which was located at approximately 10º North latitude over the eastern Pacific Ocean.

MIMIC Total Precipitable Water product

===== 10 June Update =====

Hurricane Adrian intensified to a Category 4 storm on 10 June 2011. 4-km resolution GOES 10.7 µm IR channel images (below; click image to play animation) continued to show a well-defined eye structure.

GOES 10.7 µm IR images (click image to play animation)

A closer view of the eye could be seen using 1-km resolution GOES visible channel images (below; click image to play animation).

GOES visible channel images (click image to play animation)

The intensity of Hurricane Adrian was expected to decrease as the storm began to move over colder waters, as seen on an image of the Sea Surface Temperature (SST) analysis (below).

Sea Surface Temperature (SST) analysis

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GOES-13 10.7 µm IR images

AWIPS images of 4-km resolution GOES-13 10.7 µm IR data (above) showed an area of collapsing convection (exhibiting rapidly warming cloud top IR brightness temperatures) moving northeastward across far southern Kansas on 09 June 2010. Downdrafts within this collapsing convection led to a nocturnal heat burst at Wichita (station identifier KICT) .

McIDAS images of  GOES-11 (GOES-West) and GOES-13 (GOES-East) 3.9 µm shortwave IR channel data (below) revealed that a warm “heat burst signature” (yellow color enhancement) could be more easily detected (and seen for a longer period of time) on the GOES-11 images, utilizing the more oblique satellite viewing angle from the western satellite.

GOES-11 (left) and GOES-13 (right) 3.9 µm shortwave IR images

About 2 hours after the heat burst event, a comparison of AWIPS images of 1-km resolution POES AVHRR 10.8 µm IR and 3.7 µm shortwave IR data (below) continued to show an area of slightly warmer surface IR brightness temperatures (20.0º C and warmer, yellow color enhancement) along the rear flank of the collapsing convection. Again,  the areal coverage of the warm signature was greater on the 3.7 µm shortwave IR image, since that channel is more sensitive to warmer temperatures.

POES AVHRR 10.8 µm IR and 3.7 µm shortwave IR images

An alternative view using a McIDAS image of the NOAA-19 AVHRR 3.7 µm shortwave IR channel data with plots of surface temperature (below) showed that the instrument shelter air temperatures had cooled to 79-80º F by 08:00 UTC — however, there is some question as to whether the warmest surface IR brightness temperatures seen on the image (red color enhancement) represent the core of the remnants of the heat burst signature, or simply a warm signature of the city of Wichita itself (Sedgewick county is outlined in black on the image).

NOAA-19 AVHRR 3.7 µm IR image + surface temperatures

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