Suomi NPP VIIRS 0.7 µm Day/Night Band images (pre-Sandy, and post-Sandy)

As seen in other examples posted on this blog, the Suomi NPP VIIRS 0.7 µm Day/Night Band (DNB) is useful for detecting city lights at night. A comparison of “pre-Sandy” (a cloud-free night way back on 31 August 2012) and “post-Sandy” (01 November 2012) DNB images displayed using McIDAS-V (above) showed some of the areas that remained without power in the wake of the landfall of Hurricane Sandy on 29 October 2012 — two areas that stand out are western parts of Long Island, New York and central New Jersey. You can also interactively fade between the before/after DNB images using this Java applet.

A comparison of AWIPS images of the 01 November DNB data with the corresponding 10.8-3.74 µm  “fog/stratus product” (below) showed that those two areas of interest — western Long Island, and central New Jersey — were not obscured by any significant low fog/stratus  features (yellow to red color enhancement) or any dense high cirrus clouds (black color enhancement).

Suomi NPP VIIRS 0.7 µm Day/Night Band image and “Fog/stratus product” image

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GOES-13 10.7 µm IR imagery (Click image to play animation)

GOES-13 (GOES-East), in geostationary orbit at the Equator and 75 W longitude, was well-positioned to capture the entire lifecycle of Hurricane Sandy. An animation of 10.7 µm IR images is shown above, at 3-hourly time steps, from incipient tropical wave, to a hurricane hitting Jamaica, to a system with an almost subtropical storm appearance off Florida. Note the relentless expansion of the system as it moves towards the northeast part of the US.

Another view of a portion of the lifecyle of Sandy is shown below, with GOES-13 6.5 µm water vapor channel images at 1-hour intervals during the 24 October – 30 October period. This water vapor animation is also available as a QuickTime movie.

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

===== 31 October Update =====

GOES-West / GOES-East composite IR images (click image to play QuickTime movie)

In addition to the GOES-13 perspective, here are 2 other examples that show the life cycle of Hurricane Sandy: a GOES-West / GOES-East composite of IR images covering the period 24-31 October (above; click image to play QuickTime movie), and GOES-14 Super Rapid Scan Operations (SRSO) 1-minute interval daytime visible images during the 25-31 October period (below; click image to play YouTube video). For the best YouTube viewing experience, click on the “Change quality’ icon immediately below the images and select “1080p HD” as the resolution, then put the video into Full Screen mode. The source QuickTime video of GOES-14 SRSO visible imagery is here.

GOES-14 Super Rapid Scan visible images (click image to play YouTube video)

Another way to visualize the life cycle of Sandy is to examine a Lagrangian animation, where the GOES-13 10.7 µm IR images remain centered over the core of the storm (below; click image to play animation; also available as a QuickTime movie or on YouTube).

GOES-13 10.7 µm IR images (click image to play animation)

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Suomi NPP VIIRS 0.64 µm visible channel and false-color RGB images

A comparison of AWIPS images of 1-km resolution Suomi NPP VIIRS 0.64 µm visible channel and false-color Red/Green/Blue (RGB) images (above) showed areas of light snow cover across parts of northern Minnesota and southern Ontario on 30 October 2012. The RGB image was created by using the 0.64 µm visible image as the Red component, and the 1.61 µm “snow/ice channel” image as the Green and Blue components of the image. Snow on the ground appears brighter white on the visible image, and lighter shades of red on the corresponding RGB image. This snow cover resulted from a series of weak disturbances that had moved across the region several days earlier, which produced as much as 4 inches of snow at some locations.

It is also possible to determine which lakes in the area have frozen over — for example, the shallow Lake Wabigoon just south of Dryden, Ontario (station identifier CYHD) and the larger Lake Winnipeg (east of Gimli, station identifier CYGM) appear darker red on the RGB image and light gray on the visible image.

During the previous night, a Suomi NPP VIIRS 0.7 µm Day/Night Band image at 09:08 UTC or 4:08 AM local time (below) provided a “visible image at night” that allowed the areas of snow cover to be seen due to illumination by a full Moon.

Suomi NPP VIIRS 0.7 µm Day/Night Band image

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Suomi NPP Day/Night Band and 11.45 µm imagery of Hurricane Sandy

The Full Moon that was exacerbating the high storm tides of Hurricane Sandy also allowed for stunning “night-time visible” imagery on 29 October 2012. A comparison of AWIPS images of Suomi NPP VIIRS 0.7 µm Day/Night Band and 11.45 µm IR data from shortly after 06 UTC or 2 AM EDT (above) showed the compact convective core of Hurricane Sandy east of Cape Hatteras, near the South Wall of the Gulf Stream. Sea Surface Temperature and Ocean Heat Content products from the CIMSS Tropical Cyclones site (below) indicated that later in the morning (around 12 UTC) the center of Sandy was crossing the axis of the Gulf Stream.

Sea Surface Temperature and Ocean Heat Content products

GOES-13 10.7 µm imagery (Click image to play animation)

GOES-13 was placed into in Rapid Scan Operations (RSO) mode to monitor Sandy, and 10.7 µm IR images (above; click image to play animation) showed several noteworthy aspects to the storm. The sheer size of the storm is quite evident. The cirrus shield of the storm was pushing west through lower Michigan into Wisconsin during the 16-hour time period of the animation. The IR images also showed the pulsing development of convection near the center of the storm, and the northwest motion of the entire system. The cyclonic circulation in the low-level wind field over the ocean and the anticyclonic circulation of the higher level clouds over the eastern United States was also apparent.

A morning overpass of the Metop-A satellite provided Advanced Scatterometer (ASCAT) winds around Sandy (below) — there were a number of wind vectors having speeds of 50 knots or higher (within the area of red wind vectors) in the southern quadrant of the storm.

POES AVHRR 0.86 µm visible channel image + ASCAT surface scatterometer winds

Suomi NP VIIRS 11.45 µm, MODIS 11.0 µm, and POES AVHRR 12.0 µm IR images (click image to play animation)

A sequence of 1-km resolution Suomi NPP VIIRS 11.45 µm, MODIS 11.0 µm, and POES AVHRR 12.0 µm IR images (above; click image to play animation) showed the structure of Hurricane Sandy at various times as it curved northwestward toward the US East Coast. Such an animation also serves to underscore the potential value of having access to high spatial resolution polar-orbiting satellite imagery in AWIPS, in the event of an outage of the GOES-East satellite (such as the one that occurred on 23 September 2012). CIMSS has the unique capability to provide such imagery from VIIRS, MODIS, and AVHRR to National Weather Service forecast offices.

GOES-14 0.63 µm visible channel images (click image to play HD format QuickTime movie)

During the daylight hours, GOES-14 Super Rapid Scan 0.63 µm visible channel images at 1-minute intervals (above; click image to play HD format QuickTime movie) showed great detail in the complex temporal changes of the structure of the various cloud features associated with Sandy. Note that GOES-14 remained in SRSO-R mode to monitor Sandy, and real-time 1-minute imagery is available here. In addition, a number of GOES-14 SRSO-R animations are available on the SSEC YouTube Channel.

POES AVHRR 12.0 µm IR image with surface pressure analysis

Sandy made landfall as the storm was transitioning from a hurricane to a very intense post-tropical cyclone near Atlantic City, New Jersey around 00:00 UTC on 30 October (NHC advisory archive). A large-scale POES AVHRR 12.0 µm IR image is shown above with an overlay of the surface pressure analysis; a closer view is shown below, with surface reports and buoy reports included. The storm produced as much as 12.55 inches of rain and 34 inches of snow in Tennessee, and wind gusts as high as 90 mph in New York and New Jersey (and 145 mph at Mt. Washington, New Hampshire). A listing of significant rainfall, snowfall, and wind gusts can be found in the HPC storm summary. An excellent summary of notable Superstorm Sandy statistics can be found on the Wunderblog site.

POES AVHRR 12.0 µm IR image with surface reports and buoy reports

Landfall was also captured by GOES-14 SRSO visible and IR imagery (below; also available as a QuickTime movie). Landfall occurred after sunset, so infrared imagery was an important analysis tool.

GOES-14 0.63 µm visible channel and 10.7 µm infrared images (click image for animation)

A composite of GOES-14 1-minute interval SRSO-R visible images superimposed on GOES-13 visible images — at standard 15-minute intervals early in the day, and 5-10 minute interval Rapid Scan Operations later in the day –  (below; click image to play QuickTime animation, courtesy of Rick Kohrs, SSEC) helps to highlight the value of GOES imagery at more frequent time intervals to study the evolution of complex weather systems. With the next-generation GOES-R satellite, images will be available at 30-second intervals over special mesoscale storm sectors.

GOES-13 / GOES-14 0.63 µm visible image composite (click image to play QuickTime movie)

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