The Japanese Satellite Himawari-8 was successfully launched from
southern Tanegashima Island today at 05:16 UTC. (NASA News Source). Is the plume from that launch visible in MTSAT imagery? The visible imagery with a nominal time of 0514 UTC was actually scanning Tanegashima Island at 0519 UTC, and a plume, denoted by the yellow arrow above, is visible off the southern edge of the Island. (The 0501 UTC image of the same scene, pre-launch, is here).

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The Suomi NPP VIIRS image toggle, above, from the pre-dawn hours (3:42 am local time) on 6 October 2014 shows a 0.7 µm Day/Night Band image and an 11.45 µm Infrared image, along with observations of postive and negative lightning strikes. With ample illumination by moonlight, the “visible image at night” Day/Night Band image highlighted areas of convective overshooting tops, but also included bright horizontal stripes that are associated with intense lightning activity; after scanning a particularly bright area of lightning in Arkansas, this image also showed a darker “post-saturation recovery” stripe downscan (to the southeast), which stretched from central Arkansas into Mississippi. This vigorous convective system dropped southeastward from Oklahoma towards the Gulf of Mexico, eventually becoming a Quasi-Linear Convective System (QLCS) which produced hail and wind damage (with one fatality) across parts of northeastern Texas and far northwestern Louisiana (SPC storm reports).

The southward-dropping Mesoscale Convective System followed a channel of unstable air as diagnosed by the GOES Sounder, above. Note that the Lifted Index values were smaller (less instability) along the path that the system had moved. Total Precipitable water was also enhanced in that corridor, suggesting a region where moisture return from the Gulf of Mexico was ongoing and concentrated.

Mesoscale Convective Systems can exhibit signatures that suggest the presence of turbulence in the atmosphere. In the GOES-13 IR image above, parallel filaments or “transverse bands” of cirrus  (extending approximately north-south) on the poleward side of the MCS suggest the presence of turbulence, and scattered pilot reports of Moderate Turbulence confirm that. Visible MODIS Imagery, below, also shows the transverse bands, as well as the outflow boundary arcing from Houston to the northwest and north.

An animation of hourly GOES-13 Visible imagery, below, shows the motion of the western portion of the outflow boundary as the decaying QLCS moved into the Gulf of Mexico.

GOES-13 6.5 µm water vapor channel imagery, below, displayed a signature of subsidence immediately upstream of the dissipating MCS, in the form of an arc of warmer/drier (yellow to orange color enhancement) brightness temperatures that extended from the Texas coast into central Arkansas. One rapidly-developing convective cell which formed along the advancing outflow boundary was responsible for severe turbulence in eastern Texas; the subtle signal of the westward-propagating outflow boundary could also be followed on the water vapor imagery.

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The visible imagery animation above shows stratocumulus over Wisconsin behind a strong early-season cold front. Careful examination of the animation will reveal the presence of at least three exhaust plumes from power plants over Wisconsin. Imagery from 1715 UTC, below, shows visible (0.63 µm) and infrared (3.9 µm and 10.7 µm) data (Click here for an image toggle without the Big Red Box). The plume is warmer in the 3.9 µm imagery, relative to its surroundings; the plume is cooler in the 10.7 µm imagery, relative to its surroundings (an enhanced version of the loop makes this even more evident). Why does the temperature difference exist?

Plumes appear darker — warmer — in the 3.9 µm imagery because of increased reflectivity in the plume: cloud droplets in the power plant plume are smaller and more reflective of 3.9 µm radiation than the cloud droplets in the surrounding stratocumulus field. The plume is cooler in the 10.7 µm imagery because the plume is higher in the atmosphere than the surrounding stratocumulus deck.

Suomi NPP overflew the area at 1836 UTC, and that imagery is shown below. The higher resolution data allows a better discrimination of the small plumes over the state. As with GOES data, the shortwave infrared (3.74 µm for VIIRS) data also shows warmer conditions over the plume compared to the surrounding stratocumulus deck.

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McIDAS images of GOES-15 Visible (0.63 µm) data (above) showed the hazy signature of a plume of re-suspended volcanic ash originating from the region of the Novarupta volcano in Alaska, moving southeastward over the Shelikof Strait toward Kodiak Island on 29 September 2014. The 1912 eruption of Novarupta left a very deep deposit of volcanic ash, which often gets lofted by strong winds in the early Autumn months before snowfall covers the ash (another example occurred on 22 September 2013). Surface winds gusted as high as 30 knots at regional reporting stations, with numerical models estimating terrain-enhanced winds as high as 40-50 knots over the Novarupta ash field.

An AWIPS II image of POES AVHRR Visible (0.86 µm) data (below) showed the ash plume at 22:46 UTC; a pilot report at 22:45 UTC indicated that the top of the ash plume was between 4000 and 6000 feet above ground level.

A sequence of 3 Suomi NPP VIIRS True Color Red-Green-Blue (RGB) images from SSEC RealEarth (below) indicated that the re-suspended ash plume had been increasing in areal extent during that period.

A sequence of 4-panel products from the NOAA/CIMSS Volcanic Cloud Monitoring site (below) shows False-color images, Ash/dust cloud height, Ash/dust particle effective radius, and Ash/dust loading (derived from either Terra/Aqua MODIS or Suomi NPP VIIRS data).

Hat tip to Mark Ruminski (NOAA/NESDIS) for alerting us to this event.

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