First images from Himawari-8

December 18th, 2014
Himawari-8 0.64 µm visible channel image (click to enlage)

Himawari-8 0.64 µm visible channel image (click to enlarge)

The Japan Meteorological Agency has released the first images from the AHI instrument on the Himawari-8 satellite, which was launched on 7 October this year.

This link shows full disk imagery from all 16 spectral bands. The AHI on Himawari-8 is very similar to the ABI that will fly on GOES-R.

A comparison of images using each of the 16 spectral bands is shown below, centered over the Sea of Japan. Cloud streets are seen over much of the open waters, due to the southeastward and eastward transport of very cold air from Siberia (surface analysis). Lee waves (or “mountain waves”) are evident on the water vapor bands (8, 9  and 10) downwind or southeast of the higher terrain areas on the main Japanese island of Honshu.

Comparison of the 16 AHI spectral bands, centered on the Sea of Japan (click to enlarge)

Comparison of the 16 AHI spectral bands, centered on the Sea of Japan (click to enlarge)

 Band 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
µm  0.47   0.64   0.86   1.37   1.6   2.2   3.9   6.2   7.0   7.4   8.4   9.6   10.33   11.2   12.3   13.3 

Similar comparisons of Himawari-8 images covering Hawaii, western Australia, and the far Southern Hemisphere are available on the First Light AHI Satellite Band Webapp.

As seen on the MTSAT-2 vs Himawari-8 comparison below, even at large satellite viewing angles over the far southern portion of the Southern Hemisphere (for example, between Australia/Tasmania and Antarctica) AHI imagery such as that from water vapor channels exhibits higher quality (due to factors such as improved spatial resolution, signal-to-noise ratio, data bit depth, etc).

MTSAT-2 vs Himawari-8 water vapor channel images

MTSAT-2 vs Himawari-8 water vapor channel images

Rapid cyclogenesis off the coast of Japan, with an aircraft experiencing severe turbulence

December 16th, 2014
COMS-1 6.95 µm water vapor channel images (click to play animation)

COMS-1 6.95 µm water vapor channel images (click to play animation)

McIDAS images of KARI COMS-1 6.95 µm water vapor channel data (above; click image to play animation; also available as an MP4 movie file) showed the tell-tale signatures — well-formed dry slot; distinct comma head — of rapid cyclogenesis for a pair of storms off the west and east coasts of Japan on 16 December 2014. An American Airlines passenger jet flying from Seoul, South Korea (RKSO) to Dallas/Fort Worth, Texas experienced severe turbulence at an altitude around 27,000 feet over the eastern portion of Honshu Island, Japan (media report); several passengers and crew members were injured (with some requiring hospitalization), forcing the aircraft to divert from its course and turn back to make a landing at Tokyo Narita airport (RJAA). The turbulence encounter likely occurred near the center portion of the red square which was drawn on the images whose times were within about 30 minutes of the 10:35 UTC turbulence encounter  (FlightAware track log) — note the development of a “transverse banding” signature along the western edge of the southern storm comma head feature (10:00 UTC image).  After the multi-layered clouds of the comma head departed, lee waves or “mountain waves” could be seen downwind of the high terrain of Honshu Island. It should also be noted that the flight path was in the left exit region of an intensifying upper-tropospheric jet streak (250 hPa winds).

A dry slot exhibiting much warmer brightness temperatures (brighter yellow to orange color enhancement) was seen with the more southern of the two storms, which became the dominant system as it moved northeastward and rapidly intensified from a central pressure of 998 hPa at 06 UTC to 971 hPa at 18 UTC (below). The storm was forecast to produce a large area of hurricane-force winds over the far northwestern Pacific Ocean.

MTSAT-2 6.75 µm water vapor channel images with surface analyses at 06, 12, and 18 UTC

MTSAT-2 6.75 µm water vapor channel images with surface analyses at 06, 12, and 18 UTC

An AWIPS image of MTSAT-2 water vapor channel data with overlays of the NWS Ocean Prediction Center surface analysis and Metop ASCAT scatterometer winds showed surface wind speeds as high as 55 knots (63 mph) with the southern storm and 53 knots (61 mph) with the northern storm at 11:48 UTC (below). During the day wind gusts as high as 81 knots (93 mph) were reported at the Izu Islands south of Tokyo Bay.

MTSAT-2 6.75 µm water vapor channel image, with Metop ASCAT scatterometer surface winds and surface analysis

MTSAT-2 6.75 µm water vapor channel image, with Metop ASCAT scatterometer surface winds and surface analysis

Super Typhoon Hagupit

December 4th, 2014
Advanced Dvorak Technique (ADT) intensity estimation plot

Advanced Dvorak Technique (ADT) intensity estimation plot

As seen on a plot of the Advanced Dvorak Technique (ADT) intensity estimation (above), Typhoon Hagupit underwent a period of rapid intensification in the West Pacific Ocean late in the day on 03 December 2014, reaching Super Typhoon (Category 5) intensity on 04 December. During this period of rapid intensification, COMS-1 10.8 µm IR channel images (below; click to play animation; also available as an MP4 movie file) showed the development of a well-defined eye, with very cold cloud-top IR brightness temperatures (in the -80 to -90º C range, shades of violet) in the surrounding eyewall region.

COMS-1 10.8 µm IR channel images (click to play animation)

COMS-1 10.8 µm IR channel images (click to play animation)

A nighttime comparison of Suomi NPP VIIRS 0.7 µm Day/Night Band and 11.45 µm IR channel images at 15:50 UTC on 03 December (below; images courtesy of William Straka, SSEC) showed great detail in the cloud top IR brightness temperature patterns, as well as demonstrated the “visible image at night” capability of the Day/Night Band (which benefited from an abundance of reflected moonlight from a nearly-full Moon).

Suomi NPP VIIRS 0.64 µm and 11.45 µm IR image comparison

Suomi NPP VIIRS 0.64 µm and 11.45 µm IR image comparison

A longer-term sequence (beginning on 30 November) of storm-centered COMS-1 IR images is shown below (click image to play animation).

COMS-1 10.8 µm storm-centered IR images (click to play animation)

COMS-1 10.8 µm storm-centered IR images (click to play animation)

COMS-1 0.675 µm visible channel images from the CIMSS Tropical Cyclones site (below; click image to play animation) revealed the presence of mesovortices within the eye of Hagupit, with intricatecloud-top banding structures seen surrounding the eye.

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

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

A DMSP SSMIS 85 GHz microwave image at 22:43 UTC on 04 December (below) also showed the well-defined eyewall structure of the storm.

DMSP SSMIS 85 GHz microwave image

DMSP SSMIS 85 GHz microwave image

For additional images and information on Super Typhoon Hagupit, see the VISIT Meteorological Interpretation blog.

===== 06 December Update =====

A comparison of MTSAT 10.8 µm IR and TRMM TMI 85 GHz microwave images just after 16:30 UTC on 06 December (below) showed the center of Hagupit making landfall on the island of Samar in the Philippines as a Category 3 typhoon. The slow-moving tropical cyclone dropped as much as 300-400 mm (12-16 inches) of rainfall.

MTSAT 10.8 µm IR and TRMM TMI 85 GHz microwave images

MTSAT 10.8 µm IR and TRMM TMI 85 GHz microwave images

Nuri transforms into a strong extratropical storm

November 9th, 2014
MTSAT-2 6.75 µm IR water vapor channel images (click to play animation)

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)

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 Visible Imagery (0.70 µm) over the Bering Sea, 7-10 November 2014 (click to enlarge)

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)

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