GOES-14 Super Rapid Scan Operations (SRSO) 1-minute imagery

August 13th, 2013 |
GOES-14 3.9 µm shortwave IR images (click image to play animation)

GOES-14 3.9 µm shortwave IR images (click image to play animation)

The GOES-14 satellite was placed into Super Rapid Scan Operations for GOES–R (SRSO-R) mode on 13 August 2013, providing images at 1-minute intervals over the western US. The prime features of interest were wildfires burning in southern Idaho and northern California. McIDAS images of GOES-14 3.9 µm shortwave IR data (above; click image to play animation) showed that some clouds and thunderstorms (black to cyan color enhancement) were moving over Idaho during the pre-dawn hours, but a few flickers of fire “hot spots” (brighter white enhancement) could be seen through breaks in the clouds. Northern California was cloud-free, which allowed a good view of the fire hot spots over that region. Note: real-time GOES-14 SRSO-R images are available here, here, and here.

AWIPS images of GOES-15/GOES-13 10.7 µm IR channel data (below) showed that the thunderstorms moving across Idaho were producing numerous cloud-to-ground lightning strikes, which could have ignited new fire activity.

GOES-15/GOES-13 10.7 µm IR image composite (with cloud-to-ground lightning strikes)

GOES-15/GOES-13 10.7 µm IR image composite (with cloud-to-ground lightning strikes)

An AWIPS comparison of Suomi NPP VIIRS 3.74 µm shortwave IR and 0.7 µm Day/Night Band images at 09:30 UTC or 3:30 AM local time (below) revealed that there were still hot spot signatures (brighter white enhancement on the shortwave IR image) evident as the fires in Idaho continued to burn through the night-time hours — and the large fire complexes also exhibited a very bright signature on the corresponding Day/Night Band image. Other bright areas on the Day/Night Band image were city lights.

Suomi NPP VIIRS 3.74 µm shortwave IR and 0.7 µm Day/Night Band images

Suomi NPP VIIRS 3.74 µm shortwave IR and 0.7 µm Day/Night Band images

With the arrival of daylight, GOES-14 0.63 µm visible channel images (below; click to play animation; also available as a QuickTime movie) showed the dissiparion of the thunderstorms over Idhao during the morning hours.

GOES-14 0.63 µm visible channel images (click image to play animation)

GOES-14 0.63 µm visible channel images (click image to play animation)

Farther to the south, GOES-14 0.63 µm visible channel images (below; click image to play animation) showed the morning erosion of areas of inland marine stratus, along with a variety of nearshore eddy circulations on different spatial scales: large eddies west of the Los Angeles area, and a series of tiny eddies moving southward from Point Sur.

GOES-14 0.63 µm visible channel images (click image to play animation)

GOES-14 0.63 µm visible channel images (click image to play animation)

Super Typhoon Utor

August 11th, 2013 |
MTSAT-2 0.73 µm visible channel images (click image to play animation)

MTSAT-2 0.73 µm visible channel images (click image to play animation)

MTSAT-2 0.7 µm visible channel images (above; click image to play animation) and 10.8 µm IR channel images (below; click image to play animation) showed a close-up view of the small “pinhole eye” exhibited by Super Typhoon Utor east of the island of Luzon in the Philippines on 11 August 2013. On the following day, the eyewall of Utor made landfall on Luzon, but the storm had weakened somewhat at that point (to a Category 4 intensity), due to an ongoing eyewall replacement cycle — for more details, see the “From the Lee Side” blog post on Weather Undergrouund.

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

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

Wildfires in southern Idaho

August 10th, 2013 |
GOES-15 (left) and GOES-13 (right) 0.63 µm visible channel and 3.9 µm shortwave IR channel images (click image to play animation)

GOES-15 (left) and GOES-13 (right) 0.63 µm visible channel and 3.9 µm shortwave IR channel images (click image to play animation)

A cluster of 4 major fire complexes (the Elk, Pony, McCan, and Beaver complexes) began to exhibit extreme fire behavior on during the afternoon and evening hours on 10 August 2013. A comparison of GOES-15 (GOES-West) and GOES-13 (GOES-East) 1-km resolution 0.63 µm visible channel and 4-km resolution 3.9 µm shortwave IR images (above; click image to play animation) showed 2 different perspectives of the many dense smoke plumes and the eventual development of a well-defined pyrocumulonimbus (pyroCb) cloud whose source appeared to be the Pony Complex. On the shortwave IR images, the hottest fire pixels are enhanced red.

The corresponding 4-km resolution GOES-15 and GOES-13 10.7 µm IR channel images (below; click image to play animation) revealed that the pyroCb cloud first began to exhibit IR brightness temperatures colder than -20 C  (cyan color enhancement) after 20:00 UTC or 1:00 PM local time, -40 C (green color enhancement) after 20:20 UTC or 1:30 PM local time, and -60 C (darker red color enhancement) after 00:30 UTC or 6:30 PM local time.

GOES-15 (left) and GOES-13 (right) 10.7 µm IR channel images (click image to play animation)

GOES-15 (left) and GOES-13 (right) 10.7 µm IR channel images (click image to play animation)

Several hours later, a comparison of 1-km resolution Suomi NPP VIIRS 3.74 µm and 4-km resolution GOES-13 3.9 µm shortwave IR images just after 4 AM local time (below) demonstrated the advantage of higher spatial resolution for detecting the true location of fire “hot spots” (black to yellow to red color enhancement). Note that there is also a significant westward displacement of the largest hot spot cluster on the GOES-13 image — there is a known navigation error with the GOES 3.9 µm channel imagery, which is in the process of being corrected.

Suomi NPP VIIRS 3.74 µm and GOES-13 3.9 µm shortwave IR images

Suomi NPP VIIRS 3.74 µm and GOES-13 3.9 µm shortwave IR images

Hurricane Henriette

August 8th, 2013 |
Suomi NPP VIIRS 11.45 µm IR images

Suomi NPP VIIRS 11.45 µm IR images

A sequence of three AWIPS images of 1-km resolution Suomi NPP VIIRS 11.45 µm IR data (above) showed the relatively compact cloud structure associated with Hurricane Henriette over the Eastern Pacific Ocean during the 07 August – 08 August 2013 period. Cloud-top IR brightness temperatures were as cold as -83 C (violet color enhancement) on the 08 August/11:12 UTC image. Henriette also exhibited a small eye on the 11:12 UTC and 22:26 UTC images on 08 August.

On a night-time comparison of Suomi NPP VIIRS 0.7 µm Day/Night Band  and 11.45 µm IR images at 11:15 UTC (below), it is interesting to point out that the eye could still be faintly identified on the Day/Night Band image, even though there was only a minimal amount of illumination from airglow alone (the Moon was in its early Waxing Crescent phase, at only 1-3% of full, but was actually below the horizon for this particular image).

Suomi NPP VIIRS 0.7 µm Day/Night Band and 11.45 µm IR channel images

Suomi NPP VIIRS 0.7 µm Day/Night Band and 11.45 µm IR channel images

The compact eye of Henriette was well-defined on a comparison of VIIRS 0.64 µm visible channel and 11.45 µm IR channel images at 22:26 UTC (below). Henriette was near its maximum intensity of 90 knots around this time.

Suomi NPP VIIRS 0.64 µm visible channel and 11.45 µm IR channel images

Suomi NPP VIIRS 0.64 µm visible channel and 11.45 µm IR channel images

A 1-km resolution GOES-15 0.63 µm visible channel image with an overlay of ASCAT surface scatterometer winds from the CIMSS Tropical Cyclones site (below) also showed a good presentation of the eye and the surface wind flow associated with the Henriette.

GOES-15 0.63 µm visible channel image with ASCAT surface scatterometer winds

GOES-15 0.63 µm visible channel image with ASCAT surface scatterometer winds

An animation of GOES-15 10.7 µm IR channel images (below) revealed that the eye was becoming less obvious after about 00 UTC on 09 August.

GOES-15 10.7 µm IR channel images

GOES-15 10.7 µm IR channel images