Synchronous Meteorological Satellite (SMS-1) 11 µm infrared channel image, 2130 UTC 27 June 1974 (click to enlarge)

The oldest satellite image in the SSEC data archive is shown above, taken 40 years ago on 27 June 1974, from SMS-1 (the corresponding visible image can be seen here). The infrared channel sensed radiation in a broad spectrum between 10.5 and 12.6 µm (source). The SMS-1 satellite (launched on 17 May 1974) was positioned over the Equator over eastern South America, at about 45 degrees West Longitude.

More information on the SSEC Datacenter archive is here.

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

McIDAS images of GOES-13 0.63 µm visible channel data on 20 June 2014 (above; click image to play animation; also available as an MP4 movie file) and on 21 June 2014 (below; click image to play animation; also available as an MP4 animation file) revealed the hazy signature of a veil of Saharan Air Layer (SAL) dust aloft over much of the southern and western portions of the Gulf of Mexico.

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

The hazy dust signature also showed up well in Suomi NPP VIIRS true-color Red/Green/Blue (RGB) images, as visualized using the SSEC RealEarth web map server (below).

Suomi NPP VIIRS true-color RGB images

The SAL tracking product showed the strong pulse of SAL dust emerging from the African continent on 10 June, then moving rapidly westward across the Atlantic Ocean and over the Caribbean Sea by 17 June (below; click image to play animation).

Meteosat-10 Saharan Air Layer tracking product (click to play animation)

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Suomi NPP VIIRS 0.64 µm visible channel images, with contours of GFS90 500 hPa geopotential height

AWIPS images of Suomi NPP VIIRS 0.64 µm  visible channel data (above) showed the development of early afternoon thunderstorms over the interior of Alaska as an upper-level low moved westward over the region on 19 June 2014.

An animation of VIIRS 11.45 µm IR channel images spanning the 18-19 June period (below) depicted large areas of cloudiness exhibiting cold cloud-top IR brightness temperature values in the -45 to -50º C range (darker red color enhancement). During this time some locations across the interior of Alaska received over 4 inches of rainfall, prompting the issuance of Flood Warnings for parts of the Goodpaster, Salcha, and Upper Chena Rivers.

Suomi NPP VIIRS 11.45 µm IR channel images

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Blended Total Precipitable Water product (click to play animation)

The Blended Total Precipitable Water (TPW) product (above; click image to play animation) showed areas where TPW values were in the 25-30 mm or 1.0 to 1.2 inch range (darker green to yellow color enhancement). The corresponding Percent of Normal TPW product (below; click image to play animation) indicated that these TPW values were generally in the 150-200% of normal range for this region and this time of year.

Percent of Normal Blended Total Precipitable Water product (click to play animation)

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Suomi NPP VIIRS 11.45 µm IR channel and 0.7 µm Day/Night Band images, with cloud-to-ground lightning strikes

A comparison of AWIPS images of Suomi NPP VIIRS 11.45 µm IR channel and 0.7 µm Day/Night Band data (above) showed very large areas of cold cloud-top IR brightness temperatures associated with Mesoscale Convective Systems (MCSs) over the Upper Midwest region of the US at 08:00 UTC (3:00 AM Central time) on 18 June 2014. The coldest IR brightness temperature was -88º C over far southern  Minnesota.  Numerous bright white “streaks” were seen on the Day/Night Band (DNB) image, which indicated portions of the cloud that were illuminated by intense lightning activity. Cloud-to-ground lightning strikes are also plotted on the DNB image, showing how electrically-active these storms were at the time. The western MCS initially formed over eastern South Dakota during the previous evening, producing a few tornadoes there (SPC storm reports). The eastern MCS began to form later along the Wisconsin/Illinois border region — one aircraft flying near the northern edge of a rapidly-developing thunderstorm encountered severe turbulence.

Shortly after the time of the Suomi NPP satellite overpass, a 08:21 UTC overpass of the NOAA-19 POES satellite provided AVHRR-derived CLAVR-x Cloud Top Temperature (CTT), Cloud Top Height (CTH), and Cloud Type products (below). The minimum CTT value was -84º C, and the maximum CTH value was 14 km; much of the MCS cloud shield was classified as the Overshooting Top type (magenta color).

POES AVHRR Cloud Top Temperature, Cloud Top Height, and Cloud Type products

After sunrise, McIDAS  images of GOES-13 0.63 µm visible channel data (below; click image to play animation; also available as an MP4 movie file) showed that the eroding MCS cirrus shield aloft exposed a middle-tropospheric Mesoscale Convective Vortex (MCV) which continued moving eastward across Wisconsin during the day.

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

Consecutive overpasses of the Terra and Aqua satellites provided MODIS 0.65 µm visible channel images of the region (below). The convective outflow boundary from the earlier MCS activity had acted to push the warm frontal boundary (which had been acting as a focus for convective development) south of the Wisconsin/Illinois border, leaving a relatively stable boundary layer with a weak capping inversion aloft over Wisconsin — as a result, the MCV circulation did not play a role in initiating any new convective development.

MODIS 0.65 µm visible channel images, with surface reports and surface fronts

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