GOES-15 (GOES-West) Water Vapor (6.5 µm) images (above; also available as a 52 Mbyte animated GIF) showed the development of a Hurricane Force low in the North Pacific Ocean during the 15 November – 17 November 2016 period. Surface analysis charts for this storm, produced by the Ocean Prediction Center, are shown below.

Although it was more of an oblique viewing angle, JMA Himawari-8 AHI Water Vapor (6.2 µm, 6,9 µm and 7.3 µm) images (below; also available as a 27 Mbyte animated GIF) provided a nice view of the storm on 15 November as it was intensifying to produce Hurricane Force winds.

Since the ABI instrument on GOES-R is nearly identical to the AHI, there will also be imagery from 3 water vapor bands (6.2 µm, 6.9 µm and 7.3 µm) available once GOES-R becomes operational (as GOES-16) in 2017.

 

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Fires (as seen on 07 and 10 November) continued to burn in parts of the southeast US on 14 November 2016. A sequence of 3 consecutive true-color Red/Green/Blue (RGB) images from Terra MODIS (1650 UTC), Aqua MODIS (1829 UTC) and Suomi NPP VIIRS (1913 UTC) viewed using RealEarth, above, showed the aerial extent of the dense smoke that was most concentrated over Tennessee, Georgia, North Carolina and South Carolina. With the aid of some of the 16 spectral bands on the ABI instrument aboard GOES-R, true-color images like these will be available at least once every 5 minutes over the Lower 48 states and adjacent areas.

GOES-13 (GOES-East) Visible (0.63 µm) images with plots of surface weather and visibility (below; also available as an MP4 animation) revealed that visibility was restricted to 3 miles or less at one or more sites in all of the aforementioned states. A pair of pilot reports in eastern Tennessee indicated that he top of the smoke layer was at 6000 feet above ground level.

High loading of particulate matter (PM) due to smoke led to AIRNow Air Quality Index ratings of Unhealthy (red)  to Very Unhealthy (purple) over much of that 4-state region (below).

===== 15 November Update =====

A toggle between Suomi NPP VIIRS Shortwave Infrared (3.74 um) and Day/Night Band (0.7 um) images (with and without METAR surface reports) at 0735 UTC or 3:35 am local time on 15 November (above) showed the “hot spot” signatures and bright glow from the larger fires that were burning in northern Georgia and western North Carolina. With ample illumination from the Moon — which was in the Waning Gibbous phase, at 99% of Full — smoke plumes from some of these fires could be seen drifting southward or southeastward,  thanks to the “visible image at night” capability of the Day/Night Band.

During the subsequent daytime hours, Terra MODIS and Suomi NPP VIIRS true-color RGB images (below) again revealed the vast coverage of the thick smoke — and VIIRS Aerosol Optical Depth values were quite high over South Carolina. Unhealthy AQI values persisted during much of the day across parts of Tennessee, Georgia and South Carolina.

A sampling of pilot reports (PIREPS) showed some of the impacts that the smoke was having on aviation (below).

===== 16 November Update =====

Terra/Aqua MODIS and Suomi NPP VIIRS true-color images (above) showed that much of the smoke had moved over the adjacent offshore waters of the Atlantic Ocean on 16 November.

 

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Photos taken by SSEC scientist Claire Pettersen at 1615 UTC (above) and 1623 UTC (below) revealed several examples of ice crystal cloud optics over Madison, Wisconsin on 14 November 2016.  More information on the various types of ice cloud halos can be found here and here.

1650 UTC Terra MODIS Visible (0.65 µm), near-infrared Cirrus (1.375 µm) and Infrared Window (11.0 µm) images (below) showed the patches of cirrus clouds that were over southern Wisconsin not long after the photos above were taken. Many of the cirrus cloud features over the Madison (KMSN) area appeared very thin and nearly transparent on the Visible image; they also exhibited very warm Infrared Window brightness temperature values (warmer than -20ºC), since a great deal of radiation from the warmer surface of the Earth was reaching the MODIS detectors through the thin clouds. The 1.375 µm Cirrus band is able to detect the presence of airborne particles that are efficient scatterers of light — such as cirrus cloud ice crystals, dust, volcanic ash, smoke, haze — so the thin cirrus clouds exhibited a good signature on that image.

A similar 1.37 µm Cirrus Band will be on the ABI instrument aboard GOES-R.

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Persistent moderate to severe drought (shown here, from this site) over the southeastern United States has supported the development of fires in and around the Great Smoky Mountains on 7 November 2016. True-color imagery from Terra MODIS, above, (source: MODIS Today) showed the active fires and plumes of smoke spreading northward into the Ohio River Valley.

Suomi NPP VIIRS true-color imagery also captured the smoke emanating from the active fires, and the Aerosol Optical Depth product, toggled below (data sources: RealEarth) showed the extent of the thickest smoke layer (click here for an animation that does not include the RealEarth framing).

A sequence of true-color Red/Green/Blue (RGB) images from Terra MODIS (1643 UTC), Suomi NPP VIIRS (1809 UTC) and Aqua MODIS (1824 UTC) is shown below.

The temporal evolution of the smoke was captured on GOES-13 Visible (0.63 µm) images (below; also available as an MP4 animation). Smoke reduced the surface visibility to 2.5 – 3.0 miles at some locations in Kentucky (KJKL | KLOZ) and Tennessee (KOQT), leading to EPA Air Quality Index values in the “Unhealthy” category.

===== 10 November Update =====

In the wake of a cold frontal passage on 09 November, northerly to northeasterly winds were transporting the smoke south-southwestward as the fires continued to burn on 10 November. GOES-13 Visible (0.63 µm) images, above, showed the dense smoke plumes — some of which were briefly reducing the surface visibility to less than 1 statute mile in far western North Carolina (Andrews | Franklin). In Georgia, smoke restricted the visibility to 2.5 miles as far south as Columbus.

A Pilot Report (PIREP) in northern Georgia at 1530 UTC, below, indicated that the top of the smoke layer was around 3500 feet (where the Flight Visibility was 4 miles).  Surface reports in the vicinity of that PIREP indicated a ceiling of 1500 to 1700 feet, suggesting that the dense smoke layer aloft was about 1800-2000 feet thick over northern Georgia.

The smoke plumes showed up very well on an Aqua MODIS true-color RGB image from the MODIS Today site, below.

The 1858 UTC Suomi NPP VIIRS true-color image (with fire detections) and the Aerosol Optical Depth product, below, depicted the aerial coverage of the smoke.

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