MTSAT-2 6.75 µm IR water vapor channel images (click to play animation)

Super Typhoon Nuri has completed its transition to one of the strongest extratropical cyclones ever on record in the Bering Sea (Link; Shemya Island had a gust to 96 miles per hour!). The animation above (click here for an mp4, or view it on YouTube) covers the entire lifecycle, from birth out of the ITCZ over the western Pacific to occlusion 7500 km north in the Bering Sea. (A faster animation is available as a animated gif or mp4).

Total Precipitable Water, 0000 6 November 2014 through 0600 9 November 2014 (click to enlarge)

Animations of Total Precipitable Water (from MIMIC) from 6-9 November, above, show that deep tropical moisture associated with Nuri did not make it up into the Bering Sea, but instead was shunted off to the east. Earlier, moisture from Nuri was entrained into the development of a storm in the Bering Sea on 4-5 November. A streamer of high-level moisture in the outflow from Nuri moves northeastward and eastward. That storm subsequently slipped southeastward and made landfall over the Pacific Northwest on 8 November.

Suomi NPP Day Night Band Visibe Imagery (0.70 µm) over the Bering Sea, 7-10 November 2014 (click to enlarge)

Suomi NPP overflew the developing storm in the Bering Sea about every twelve hours, and the imagery above, from the GINA Direct Broadcast Antenna at the University of Alaska-Fairbanks, shows the rapid development of a tight swirl of clouds by early on 8 November. Subsequently, the weakening storm drifted northward through the Bering Sea.

GOES-15 also viewed the strong development, both in the window channel (YouTube video) and in the water vapor channel (YouTube video (Color Enhanced)). The visible animation, below, shows a strong cyclone by 0300 UTC on 8 November; at the subsequent sunrise, 2000 UTC, the system had occluded.

GOES-15 0.62 µm IR Visible Imagery on 7, 8 and 9 November 2014 (click to play animation)

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GOES-15 6.5 µm water vapor images and atmospheric motion vector (AMV) winds

As seen on a sequence of 3-hourly GOES-15 (GOES-West) 6.5 µm water vapor images with satellite-derived atmospheric motion vector (AMV) winds from the CIMSS Tropical Cyclones site (above), a weak but persistent trough aloft over the Hawai’i region was acting to destabilize the atmosphere and create an environment conducive to the development of widespread showers and thunderstorms — some of which were producing heavy downpours over parts of the island chain — during the 04-05 November 2014 period.

Due to radar outages, the NWS forecast office in Honolulu HI requested that the GOES-15 satellite be placed into Rapid Scan Operations (RSO) mode (NOAA/NESDIS bulletin), providing 10 images per hour (compared to only 4 per hour during routine operations). An animation of GOES-15 0.63 µm visible channel images (below; click image to play animation) begins at 17:30 UTC with routine 15-minute interval images, and then after 21:30 UTC transitions into the RSO images to demonstrate how the development and motion of features can be more carefully monitored with improved temporal resolution.

GOES-15 0.63 µm visible channel images (click to play animation)

Additional details on GOES-15 RSO sectors which were implemented during October 2014 can be found here.

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Advanced Dvorak Technique (ADT) intensity estimate for Super Typhoon Nuri

A plot of the Advanced Dvorak Technique (ADT) intensity estimation for Super Typhoon Nuri (above) shows that the tropical cyclone went through a period of rapid intensification early in the day on 02 November 2014, reaching Super Typhoon strength with sustained winds of 155 knots later in the day.

During this period of rapid intensification, MTSAT-2 10.8 µm IR channel images (below; click image to play animation; also available as an MP4 movie file) showed the development of a small “pinhole” eye (with a diameter of about 15 km); as the storm began to recurve to the north and northeast, a bit of trochoidal motion or “wobble” of the eye was also evident. The coldest cloud-top IR brightness temperatures were -88º C (darker violet color enhancement).

MTSAT-2 10.8 µm IR channel images (click to play animation)

A 375-meter resolution Suomi NPP VIIRS 11.45 µm IR channel image (below; courtesy of William Straka, SSEC) showed great detail in the storm top temperature structure within the eyewall region of Nuri at 17:12 UTC or 2:12 am local time.

Suomi NPP VIIRS 11.45 µm IR channel image

During the daylight hours,  the COMS-1 satellite provided 15-minute interval 0.675 µm visible channel images (below; click image to play animation; also available as an MP4 movie file) which revealed the presence of mesovortices within the eye of Super Typhoon Nuri.

COMS-1 0.675 µm visible channel images (click to play animation)

============================= Added 11/04/2014 =====================

Suomi NPP VIIRS 0.7 µm Day Night Band and 11.45 µm Infrared imagery during the overnight hours (16:49 UTC or 1:49 am local time) on 03 November showed a strong, well-organized system. Ample illumination from the Moon in a Waxing Gibbous phase (94% of full) helped to highlight the “visible image at night” capability of the Day/Night Band.

Suomi NPP VIIRS Day Night Band and 11.45 µm Infrared images of the typhoon eye (click to enlarge)

Suomi NPP VIIRS Day Night Band and 11.45 µm Infrared images of the typhoon (click to enlarge)

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GOES-13 3.9 µm shortwave infrared channel images (click to enlarge)

The launch of an Antares rocket from Wallops Island, Virginia, failed on October 28th (NASA Statement on the failure). The thermal signature from the explosion and fire is evident in the animation of GOES-13 3.9 µm imagery above, within the red circle: the IR brightness temperature was 292.2K on the 22:30 UTC image (darker black pixel), compared to 286.9 and 286.7 K on the 22:15 UTC and 22:45 UTC images, respectively. The nominal time of the satellite image with the warm pixel is 22:30; however, the actual satellite scan time at Wallops Island’s latitude is 22:33 UTC. The launch was at 22:22 UTC.

On a side note, another feature that stands out in the GOES-13 3.9 µm images is the warm signature (darker black enhancement) of the waters of the Gulf Stream. A comparison of the Suomi NPP VIIRS Sea Surface Temperature product at 06:47 UTC (2:47 am local time) and 18:11 UTC (2:11 pm local time), below, showed a number of eddy features along the edges of the warm (darker red) Gulf Stream.  Strong winds associated with a Nor’easter storm several days earlier helped to create these eddies.

Suomi NPP VIIRS Sea Surface Temperature product (click to enlarge)

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