GOES-14 0.63 µm visible channel images (click image to play animation)

McIDAS images of GOES-14 0.63 µm visible channel data (above; click image to play animation) showed Tropical Storm Barbara as it intensified to Category 1 hurricane shortly before making landfall along the coast of the Gulf of Tehuantepec in southeastern Mexico on 29 May 2013. Since reliable records began for the Eastern Pacific Basin in 1966, Hurricane Barbara was the second-earliest hurricane landfall, as well as the easternmost landfall location.

An AWIPS image of ASCAT surface scatterometer winds overlaid on a GOES IR image (below) depicted a maximum wind speed of 53 knots at 16:01 UTC (while Barbara was still at tropical storm intensity).

ASCAT surface scatterometer winds

A 375-meter resolution Suomi NPP VIIRS 11.45 µm IR image at 19:35 UTC (below) showed the very cold cloud-top IR brightness temperatures (primarily in the -80 to -90 C range, enhanced with varying shades of violet) associated with convective clusters around the center of Hurricane Barbara as the storm was making landfall along the Mexican coast.

Suomi NPP VIIRS 11.45 µm IR image

 ===== 30 May Update =====

GOES-14 0.63 µm visible channel images (below; click image to play animation) seem to suggest that the low-level circulation of Barbara remained intact after crossing the rugged terrain of southern Mexico, and emerged into the Gulf of Mexico on 30 May. The GOES-14 satellite had been placed into Rapid Scan Operations (RSO), providing images as frequently as every 5-10 minutes.

GOES-14 0.63 µm visible channel images (click image to play animation)

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Suomi NPP VIIRS 1.61 µm “snow/ice discrimination channel” images

A sequence of AWIPS images of Suomi NPP VIIRS 1.61 µm near-IR “snow/ice discrimination channel” data covering the period from 13:47 UTC on 27 May to 23:24 UTC on 28 May 2013 (above) showed the effects of ice jam flooding along the Yukon River in the vicinity of Galena, Alaska (station identifier PAGA). In addition to snow and ice, water is also a strong absorber at the 1.61 µm near-IR wavelength — so it appears darker on the images. This dark signature of water inundation can be seen increasing in areal coverage during that 1.5 day period. This flooding forced the evacuation of around 300 residents of Galena, as many homes were extensively damaged by the flooding.

A comparison of Suomi NPP VIIRS 0.64 µm visible channel, 0.86 µm “land/water discrimination channel”, and 1.61 µm “snow/ice discrimination channel” images at 21:43 UTC on 28 May (below) showed that the Yukon River downstream of Galena was still snow/ice covered (appearing brighter white on the 0.64 µm and 0.86 µm images). Meanwhile, the darker signature of floodwaters near and upstream of Galena was evident to some extent on the 0.86 µm image, but was even more pronounced on the 1.61 µm image. The Yukon River ice jam flooding in the Galena area occurred about a week after similar ice jam flooding occurred much farther upstream in the Fort Yukon area.

Suomi NPP VIIRS 0.64 µm visible channel, 0.86 µm land/water discrimination channel, and 1.61 µm snow/ice discrimination channel images

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GOES-14 6.5 µm water vapor channel images (click image to play animation)

An unusual late-season nor’easter storm produced heavy rainfall (as much as 6.14 inches at Whiting, Maine) and heavy snow (as much as 13.4 inches at Mount Mansfield in Vermont and 34 inches at Whiteface Mountain, New York) during the 24 May – 26 May 2013 period. McIDAS images of GOES-14 6.5 µm water vapor channel data (above; click image to play animation) displayed some interesting storm structures during the 25-26 May timeframe.

AWIPS images of the MIMIC Total Precipitable Water product (below; click image to play animation) showed that a long atmospheric river was transporting abundant tropical moisture northward, which was then wrapping inland around the storm circulation.

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

A comparison of 1-km resolution Suomi NPP VIIRS 0.7 µm Day/Night Band and 11.45 µm IR channel images at 05:52 UTC or 1:52 AM local time on 26 May (below) showed cloud features associated with the storm as it was centered just off the coast of Maine. Strong northerly/northwesterly winds along the back side of the storm (gusting as high as 102 mph at Mt. Washington, New Hampshire) were producing bands of orographic waves clouds over parts of Vermont and New York. This example helps to highlight the “visible image at night” capability of the VIIRS Day/Night Band (given ample illumination by moonlight).

Suomi NPP VIIRS 0.7 µm Day/Night Band abd 11.45 µm IR channel images (with overlay of surface analysis)

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CONUS view of GOES 10.7 µm Longwave Infrared (IR Window) imagery

At 10:00 UTC on 23 May, GOES-14 imagery started flowing to AWIPS as the GOES-East satellite (as seen in the comparison between the 09:30 and 10:10 UTC IR images above). Work continues on evaluating the status of GOES-13. GOES-14 remains in geostationary orbit at 105.5 West longitude, and GVAR data are being broadcast directly from GOES-14 (not relayed through GOES-13). Updates on GOES-13 — and all satellites — can be found here.

GOES sounder water vapor channel (6.5 µm) imagery from GOES-13 and GOES-14

Sounder data from GOES-14 are also flowing into AWIPS. The 6.5µm water vapor channel imagery from the GOES Sounder is much cleaner on GOES-14 than on GOES-13, as shown in the image comparison above. Note also that the Sounder footprint is slightly different between GOES-13 (positioned at 75 W) and GOES-14 (positioned at 105.5 W).

GOES-14 0.63 µm visible channel images (click image to play animation)

For the first 24 hours or so, users will notice some slight problems with the accuracy of the Image Navigation and Registration (INR), as can be seen in a sequence of GOES-14 0.63 µm visible channel images (above; click image to play animation).

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