GOES-12 0.65 µm visible channel images

An explosive eruption of the Puyehue-Cordón Caulle volcano in Chile occurred on 04 June 2011. GOES-12 0.65 µm visible channel images (above) showed a darker gray ash cloud punching above the meteorological cloud deck around 18:15 UTC, with the ash cloud quickly spreading southeastward and moving over Bariloche, Argentina (station identifier SAZS).

A comparison of GOES-12 3.9 µm shortwave IR and 10.7 µm IR window channel images (below) revealed a pronounced and persistent “hot spot” signature (dark black pixels) at the summit of the volcano on the shortwave IR images — while the long and narrow cold high-altitude volcanic cloud (exhibiting IR brightness temperatures around -60º C, darker red color enhancement) could be seen spreading southeastward for a great distance on the IR window images.

GOES-12 3.9 µm shortwave IR (top) and 10.7 µm IR window (bottom) images

CIMSS activities in the GOES-R Proving Ground include the generation of real-time volcanic ash retrieval products (using Meteosat SEVIRI data as a proxy for GOES-R data), which showed a significant volcanic ash plume emerging over the Atlantic Ocean (below).

SEVIRI volcanic ash retrieval products

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MODIS true color and false color images

250-meter resolution MODIS true color and false color Red/Green/Blue (RGB) images from the SSEC MODIS Today site (above) showed the long, dense smoke plume (gray on the true color image) and the hottest active fires  (pink on the false color image) around the perimeter of the large burn scar of the “Wallow Fire” in eastern Arizona on 03 June 2011. At over 106,000 acres, the Wallow Fire has become the 4th largest wildfire in Arizona history.

===== 04 JUNE UPDATE =====

1-km resolution GOES-13 0.63 µm visible channel images (below; click image to play animation) showed the development of a very large pyrocumulus  cloud late in the afternoon on 04 June 2011 (note: the date labels on some of the images are incorrect; the Rapid Scan Operations animation spans from 16:02 UTC on 04 June to 00:55 UTC on 05 June).

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

A comparison of SSEC MODIS Today 250-meter resolution true color and false color Red/Green/Blue (RGB) images (below) from the Terra satellite (17:38 overpass time) and the Aqua satellite (20:53 UTC overpass time) showed a more detailed view of the development of the pyrocumulus cloud (brighter white, within the gray colored smoke plume on the true color image), as well as the flare-up of very hot active fires (pink features in the false color image).

MODIS true color Red/Green/Blue (RGB) images

MODIS false color Red/Green/Blue (RGB) images

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GOES-13 10.7 µm IR images + SPC severe weather reports

AWIPS images of 4-km resolution GOES-13 10.7 µm IR images with overlays of SPC storm reports (above) showed the large Mesoscale Convective System that moved across the New England region of the US on 01 June 2011. This was part of a long line of thunderstorms that stretched from Maine to West Virginia, as seen on POES AVHRR 0.63 µm visible images (below).

POES AVHRR 0.63 µm visible channel images

One of the more notable events was a tornado that produced EF-3 damage in the Westfield and Springfield areas in southwestern Massachusetts. Images of GOES-13 10.7 µm IR images with an overlay of the Automated Overshooting Top Detection product (below) revealed a overshooting top (OT) just to the northwest of Westfield (station identifier KBAF) at 20:02 UTC — about 28 minutes later the tornado was reported in Westfield at 20:30 UTC (also see the NOAA Hazardous Weather Testbed blog). It is important to mention that the OT markers as plotted in AWIPS are parallax-corrected, which moves them slightly to the southeast of the coldest cloud tops on the non-parallax-corrected GOES IR imagery in AWIPS.

Note that another OT was detected farther to the north at 19:45 UTC, with the cell that later produced damaging winds at Northampton at 19:58 UTC. and Hadley at 20:15 UTC.

GOES-13 10.7 µm IR images + Automated Overshooting Top Detection

A 1-km resolution POES AVHRR 10.8 µm IR image at 20:39 UTC with an overlay of the cumulative SPC storm reports up to that time (below) offered a more detailed view of the cold storm top IR brightness temperatures (which were as cold as -79º C).

POES AVHRR 10.8 µm IR image + cumulative SPC storm reports

CIMSS participation in GOES-R Proving Ground activities includes making POES AVHRR images and products available for National Weather Service offices to add to their local AWIPS workstations, as well as the testing and evaluation of products such as Automated Overshooting Tops Detection during the NOAA Hazardous Weather Testbed. The VISIT training lessons “POES and AVHRR Satellite Products in AWIPS” and “Objective Satellite-Based Overshooting Top and Enhanced-V Anvil Thermal Couplet Signature Detection” are available to help users understand these products and their applications to weather analysis and forecasting.

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GOES-13 6.5 µm water vapor images (click to play animation)

An area of organized convection was seen moving rapidly southwestward across the western Atlantic Ocean on 31 May 2011, not far off the East Coast of the US. AWIPS images of GOES-13 6.5 µm “water vapor channel” data (above; click image to play animation) suggested that this area of convection over the Atlantic (which was designated Atlantic Tropical Invest 93L on the morning of 01 June) may have been due to a residual Mesoscale Convective Vortex (MCV) that was created by a large Mesoscale Convective System (MCS) over the Upper Midwest region of the US 2 days earlier (for additional information, see the WeatherMatrix Blog and the Weather Underground WunderBlog). A comparison of a POES AVHRR 0.63 µm visible image at 12:37 UTC with ASCAT scatterometer surface winds about 2 hours later at 14:40 UTC (below) revealed a well-defined cyclonic circulation within the convective cluster on 31 May.

POES AVHRR 0.63 µm visible channel image + ASCAT scatterometer surface winds

MODIS Sea Surface Temperature (SST) product images (below) indicated that the SST values within the Gulf Stream were in the upper 70s to low 80s F (darker red color enhancement) — and these warm waters may have helped the MCV convection to organize and intensify as it eventually moved southwestward over the Gulf Stream.

MODIS Sea Surface Temperature product images

The feature could also be followed on the MIMIC Total Precipitable Water (TPW) product (below; click image to play animation) — TPW values remained above 40-45 mm during the entire journey across the western Atlantic Ocean, and peaked at 58 mm at 18:00 UTC on 31 May as the disturbance began to move over the warmer waters of the Gulf Stream.

MIMIC Total Precipitable Water (TPW) product (click to play animation)

A sequence of MODIS 11.0 µm IR and POES AVHRR 10.8 µm IR images (below) showed minimum cloud top IR brightness temperature values in the -71º C to -83º C range during the 31 May to 01 June period.

MODIS 11.0 µm IR + POES AVHRR 10.8 µm IR images

A somewhat similar case was noted back in July 1999, when MCV-related convection moved inland produving large hail, damaging winds, and heavy rain in parts of North Carolina and South Carolina.

CIMSS participation in GOES-R Proving Ground activities includes making a variety of POES AVHRR, MODIS, and MIMIC TPW images and products available for National Weather Service offices to add to their local AWIPS workstations. The VISIT training lessons “POES and AVHRR Satellite Products in AWIPS”, “MODIS Products in AWIPS“, and “Morphed TPW Detection (MIMIC)” are available to help users understand these products and their applications to weather analysis and forecasting.

[Added, 7 June 2011: An enhanced infrared loop using data from GOES-13 that shows the entire life of the MCV is available here. Note: 34 megabyte file size]

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