POES AVHRR 0.86 µm visible channel and 12.0 µm IR channel images

A strong storm (with a central pressure near 950 hPa or 28.05″) had been intensifying over the Gulf of Alaska on 02 November 2012, and eventually began to enhibit a classic tightly-wrapped signature of a cyclone that had reached the occluded stage on POES AVHRR 0.86 µm visible channel and 12.0 µ IR images at 19:05 UTC (above) and also on MODIS 0.64 µm visible channel and 11.0 µm IR channel images at 21:00 UTC (below). This storm was producing widespread storm-force winds, with some gusts to hurricane force over the western Gulf of Alaska.

MODIS 0.64 µm visible channel and 11.0 µm IR channel images

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MODIS 0.65 µm visible channel and false-color Red/Green/Blue (RGB) images

Cold air and upslope flow on the western side of Hurricane Sandy contributed to some very impressive snowfall totals across parts of the central Appalachian Mountains in the eastern US (HPC storm summary)| HPC snowfall contour map). Once some of the cloud cover began to clear from the region on 02 November 2012, a comparison of AWIPS images of visible channel data and false-color Red/Green/Blue (RGB) composites from MODIS at 16:09 UTC or 12:09 PM local time (above) and again at 17:55 UTC or 1:55 PM local time (below) revealed the extent of the remaining high-elevation snow cover. On the false-color RGB images (created using the 2.1 µm “snow/ice channel” on MODIS, and the 1.61 µm “snow/ice channel” on VIIRS as the Green and Blue components of the image composites), snow cover appeared as the darker red features (which also appeared white on the corresponding visible images).

Data from the National Operational Hydrologic Information Center (observed snow depth | model-derived snow depth) indicated that some sites still had a snow depth in excess of 20 inches on on the morning of 02 November.

Suomi NPP VIIRS 0.64 µm visible channel and false-color Red/Green/Blue (RGB) images

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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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