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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GOES-13 0.63 µm visible channel images (click image to play animation)

The Wallow Fire continued to burn out of control, becoming the second largest fire on record in the state of Arizona on 07 June 2011. McIDAS images of 1-km resolution GOES-13 0.63 µm visible channel data (above; click image to play animation) showed the dense plume of smoke that stretched from Texas northward to Minnesota and Wisconsin (this was smoke from the previous day of burning).

AWIPS images of GOES-13 visible channel data (below) showed a closer view of areas of smoke of varying height and density covering the Upper Midwest region of the US. The areal coverage of the smoke became more apparent later in the day, as the forward scattering angle increased between the GOES-13 satellite (positioned at 75º West longitude) and the setting sun.

GOES-13 0.63 µm visible channel images (click image to play animation)

A line of convective cells began to develop around sunset along the Minnesota-Wisconsin border (below) — these towering cumulonimbus clouds were able to cast very long shadows (some over 100 miles long) onto the top of the dense smoke layer below.

GOES-13 0.63 µm visible channel image

During the middle of the day, when the forward scattering angles are not as favorable to allow the best view of the areal coverage of the smoke, other satellite channels can be employed to help locate the areas where the smoke is most dense. Two comparisons of 1-km resolution MODIS 0.65 µm visible channel and the MODIS near-IR 1.38 µm “cirrus detection” channel data (below) demonstrated the utility of the cirrus channel for helping to locate the areas where the smoke was most dense during the daytime at 16:21 UTC and 19:21 UTC. The cirrus detection channel is helpful at identifying airborne particles that are efficient scatterers of light (ice crystals, dust particles, smoke particles) — so the thicker areas of smoke showed up as the slightly brighter arc-shaped features across pars of Kansas, Iowa, and Wisconsin.

MODIS 0.65 µm visible channel and 1.38 µm "cirrus detection" channel images

MODIS 0.65 µm visible channel and 1.38 µm "cirrus detection" channel images

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