Eruption of Kambalny volcano in Kamchatka, Russia

March 25th, 2017 |

Himawari-8 Visible (0.64 µm) and Infrared Window (10.4 µm) images [Click to play animation]

Himawari-8 Visible (0.64 µm) and Infrared Window (10.4 µm) images [Click to play animation]

The Kambalny volcano in far southern Kamchatka, Russia erupted around 2120 UTC on 24 March 2017. A Himawari-8 “Target Sector” was positioned over that region — providing rapid-scan (2.5-minute interval) imagery — as seen in a 2-panel comparison of AHI Visible (0.64 µm) and Infrared Window (10.4 µm) data covering the first 7 hours of the eruption (above). Ash plume infrared brightness temperatures quickly became -40ºC and colder (bright green enhancement).

Himarari-8 false-color RGB images [click to play animation]

Himarari-8 false-color RGB images [Click to play animation]

Himawari-8 false-color Red/Green/Blue (RGB) images from the NOAA/CIMSS Volcanic Cloud Monitoring site (above) showed the ash plume drifting south-southwestward during the subsequent nighttime hours. It is interesting to note the formation and subsequent northwestward motion of numerous contrails (darker green linear features) across the region, due to the close proximity of a major Tokyo flight corridor. The contrail signatures

True-color RGB images from Terra MODIS, Suomi NPP VIIRS and Aqua MODIS, viewed using RealEarth (below) revealed the long ash plume during the late morning and early afternoon on 25 March. The dark signature of ash fall onto the snow-covered terrain was evident on the Terra and Aqua images, just west of the high-altitude ash plume.

Terra MODIS, Suomi NPP VIIRS and Aqua MODIS true-color RGB images [Click to enlarge]

Terra MODIS, Suomi NPP VIIRS and Aqua MODIS true-color RGB images [Click to enlarge]

26 March Update: a closer view of Terra MODIS true-color images from 25 and 26 March (below) showed that the perimeter of the darker gray surface ash fall signature had fanned out in both the west and east directions.

Terra MODIS truecolor RGB images from 25 and 26 March, with arrows indicating the perimeter of surface ash fall signatures on each day [Click to enlarge]

Terra MODIS truecolor RGB images from 25 and 26 March, with arrows indicating the perimeter of surface ash fall signatures on each day [Click to enlarge]

Winter storm from the Upper Midwest to the Northeast US

March 15th, 2017 |

GOES-16 Water Vapor (6.9 µm) images, with hourly plots of surface weather [click to play MP4 animation]

GOES-16 Water Vapor (6.9 µm) images, with hourly plots of surface weather [click to play MP4 animation]

** The GOES-16 data posted on this page are preliminary, non-operational data and are undergoing testing. **

A winter storm produced heavy snow across parts of the Upper Midwest on 13 March 2017, and then merged with subtropical jet stream energy to help develop an intense and rapidly-deepening storm which affected much of the Northeast US during 14 March15 March (WPC storm summary). GOES-16 ABI Water Vapor (6.9 µm) images covering the 13-15 March period (above) showed the development and motion of this complex storm. .

A closer view of the Northeast US on 14 March (below) displayed some of the complex banding structures associated with the deepening storm, and also showed the sharp gradient of precipitation type along the coastal areas. Notable weather impacts included a storm total snowfall of 48.4 inches at Hartwick, New York, a new all-time 24-hour snowfall accumulation of 31.1 inches at Binghamton, New York, 0.4 inch of freezing rain accumulation at Chesilhurst, New Jersey and a wind gust of 77 mph at Plum Island, Massachusetts.

GOES-16 Water Vapor (6.9 um) images, with hourly surface weather symbols [click to play animation]

GOES-16 Water Vapor (6.9 um) images, with hourly surface weather symbols [click to play animation]

Some interesting features were also seen in the wake of the large Northeast US component of the storm. For example, a GOES-16 Mesoscale Sector provided 1-minute interval  0.5-km resolution Visible (0.64 µm) imagery of lake effect snow bands streaming southward off Lake Michigan on 14 March, which produced heavy snow in parts of southeastern Wisconsin, northeastern Illinois and northwestern Indiana (below).

GOES-16 Visible (0.64 µm) images, with hourly surface plots [click to play MP4 animation]

GOES-16 Visible (0.64 µm) images, with hourly surface plots [click to play MP4 animation]

GOES-16 6.2 µm, 6.9 µm and 7.3 µm Water Vapor images (below) revealed widespread mountain waves downwind of the southern Appalachians on 15 March.

GOES-16 Water Vapor images: 6.2 µm (top), 6.9 µm (middle) and 7.3 µm (bottom) [click to play animation]

GOES-16 Water Vapor images: 6.2 µm (top), 6.9 µm (middle) and 7.3 µm (bottom) [click to play animation]

These mountain waves were responsible for a few pilot reports of moderate turbulence, two of which are highlighted below.

GOES-13 Water Vapor (6.5 µm) image, with pilot report of turbulence [click to enlarge

GOES-13 Water Vapor (6.5 µm) image, with pilot report of turbulence [click to enlarge]

GOES-13 Water Vapor (6.5 µm) image, with pilot report of turbulence [click to enlarge]

GOES-13 Water Vapor (6.5 µm) image, with pilot report of turbulence [click to enlarge]

GOES-16 water vapor imagery: wave structures within a dry slot

March 8th, 2017 |

GOES-16 Water Vapor images: 6.2 µm (top), 6.9 µm (middle) and 7.4 µm (bottom) [click to play animation]

GOES-16 Water Vapor images: 6.2 µm (top), 6.9 µm (middle) and 7.4 µm (bottom) [click to play animation]

** The GOES-16 data posted on this page are preliminary, non-operational data and are undergoing testing. **

(Hat tip to T.J. Turnage, NWS Grand Rapids, for alerting us to this case): A variety of mesoscale wave structures were seen in NOAA GOES-16 Lower-Tropospheric Water Vapor (7.3 µm) and Middle-Tropospheric Water Vapor 6.9 µm images (above; also available as an MP4 animation) within a dry slot along the southern periphery of a trough associated with a large and intense mid-latitude cyclone centered over Hudson Bay, Canada on 08 March 2017. Beneath this dry slot, wind gusts exceeded 60 mph across southern portions of Minnesota, Wisconsin and Lower Michigan as momentum aloft was mixed downward to the surface.

Using the GOES-13 (GOES-East) Sounder water vapor bands as a proxy for the three ABI water vapor bands, weighting functions calculated using 12 UTC rawinsonde data from Chanhassen, Minnesota (below) showed a dramatic downward shift in the weighting function curves (compared to a US Standard Atmosphere) — this meant that the 3 water vapor bands were sensing radiation from layers much closer to the surface on 08 March (where the strong winds could interact with terrain and cause standing waves to form). It is interesting to note that the outline of the southern part of Lake Michigan could be seen on GOES-16 Lower-Tropospheric Water Vapor (7.3 µm) imagery (animated GIF | MP4 animation) — the signal of the thermal contrast between the lake water (MODIS SST values in the upper 30s to low 40s F) and the adjacent land surfaces (MODIS LST values in the middle 50s to low 60s F) was “bleeding up” through what little water vapor was present aloft.

GOES-13 Sounder water vapor weighting functions: 12 UTC Chanhassen, Minnesota sounding vs US Standard Atmosphere [click to enlarge]

GOES-13 Sounder water vapor weighting functions: 12 UTC Chanhassen, Minnesota sounding vs US Standard Atmosphere [click to enlarge]

A comparison of GOES-16 Visible (0.64 µm) and Middle/Lower-Level Water Vapor images (below; also available as an MP4 animation) showed that these water vapor wave structures were forming in cloud-free air — this is a signature of the potential for low-altitude turbulence.

GOES-16 images: 0.64 µm Visible (top), 6.9 µm Water Vapor (middle) and 7.4 µm Water Vapor (bottom) [click to play animation]

GOES-16 images: 0.64 µm Visible (top), 6.9 µm Water Vapor (middle) and 7.4 µm Water Vapor (bottom) [click to play animation]

In fact, there were widespread pilot reports of moderate turbulence within the dry slot (below), with a few isolated reports of severe to even extreme turbulence in eastern Wisconsin and southern Lower Michigan.

GOES-13 Water Vapor (6.5 µm) images, with pilot reports of turbulence [click to play animation]

GOES-13 Water Vapor (6.5 µm) images, with pilot reports of turbulence [click to play animation]

Turbulence over the central Pacific Ocean

December 27th, 2016 |
Himawari-8 Water Vapor Imagery (6.2 µm, top; 6.9 µm, middle; 7.3 µm, bottom), 1700-1900 UTC on 27 December 2016 [click to enlarge]

Himawari-8 Water Vapor Imagery (6.2 µm, top; 6.9 µm, middle; 7.3 µm, bottom), 1700-1900 UTC on 27 December 2016 [click to enlarge]

Turbulence over the Pacific Ocean affected at least one flight on Tuesday 27 December 2016 near 24º N, 162º E, as indicated by a pilot report issued at 1745 UTC:

PGUA UUA /OV 24N 162E/TM 1745/FL340/TP B777/TB MOD-SEV/RM ZOA

In the animation above of the three Himawari-8 Water Vapor bands (sensing radiation emitted at 6.2 µm, 6.9 µm and 7.3 µm), a characteristic banded gravity wave structure is evident which is associated with the pilot report of moderate to severe turbulence (Note: the ABI instrument on the GOES-R series of satellites will feature these same 3 upper level, mid-level and lower level water vapor bands). In contrast to a turbulence event earlier this month, documented here on this blog, the wave features responsible for this turbulence were more distinct in 8-bit McIDAS-X imagery, and were also apparent in all three water vapor bands.

The Himawari-8 satellite data were used in the subsequent issuance of a SIGMET (Significant Meteorological Information) advisory:

WSPA06 PHFO 271824
SIGPAS

KZAK SIGMET SIERRA 1 VALID 271825/272225 PHFO-
OAKLAND OCEANIC FIR MOD OCNL SEV TURB FCST BTN FL280 AND FL360.
WI N2640 E16810 – N2120 E16810 – N2120 E16240 – N2640 E16250
– N2640 E16810. MOV E 25KT. BASED ON ACFT AND SAT.

The full 11-bit McIDAS-V imagery from the 6.2 µm Water Vapor band on Himawari-8, below, shows multiple ephemeral signatures of potential turbulence. In contrast to the event on 14 December, the gravity waves in this event perturbed clouds enough that they were also apparent in the Infrared Window band, as shown in this toggle between the 10.4 µm and 6.2 µm images. Himawari-8 Infrared Window brightness temperatures exhibited by the gravity wave were in the -30º to -40ºC range at 1740 UTC, which roughly corresponded to altitudes of 30,000-34,000 feet according to data from the 12 UTC rawinsonde report from Minamitorishima RJAM (IR image | text) located about 890 km or 550 miles to the west of the wave feature. Additional Himawari-8 Water Vapor images created using AWIPS II are here for the 6.2 µm imagery (from 1720-1740 UTC); this is a toggle between 6.2 µm and 7.3 µm imagery at 1720 UTC.

Himawari-8 Infrared Imagery (6.2 µm), 1600-1900 UTC on 27 December 2016 [click to animate]

Himawari-8 Water Vapor (6.2 µm) Imagery, 1600-1900 UTC on 27 December 2016 [click to animate]

The superior spatial resolution of Himawari-8 (2-km at the sub-satellite point) was vital in detecting the gravity wave features causing the turbulence. Water Vapor imagery from COMS-1, with a nominal resolution of 4 km, does not show the features associated with the turbulence report.

COMS-1 Infrared Imagery (6.75 µm), 1630-1800 UTC on 27 December 2016 [click to animate]

COMS-1 Water Vapor (6.75 µm) Imagery, 1630-1800 UTC on 27 December 2016 [click to animate]

Similarly, HimawariCast data that is broadcast at reduced resolution was insufficient to monitor this event. See the toggle below from 1740 UTC.

Himawari-8 Infrared Imagery (6.2 µm) at 1740 UTC on 27 December 2016, native resolution and as distributed via Himawaricast [click to enlarge]

Himawari-8 Water Vapor (6.2 µm) Imagery at 1740 UTC on 27 December 2016, at native resolution and as distributed via Himawaricast [click to enlarge]