Holy Fire in southern California, as viewed by 4 GOES

August 9th, 2018 |
Shortwave Infrared (3.9 µm) images from GOES-15, GOES-14, GOES-17 and GOES-16 [click to play MP4 animation]

Shortwave Infrared (3.9 µm) images from GOES-15, GOES-14, GOES-17 and GOES-16 [click to play MP4 animation]

 * GOES-17 images shown here are preliminary and non-operational *

GOES-15 (GOES-West), GOES-14, GOES-17 and GOES-16 (GOES-East) Shortwave Infrared (3.9 µm) images (above) showed the thermal anomaly or “hot spot” (black to yellow to red pixels) associated with the Holy Fire that was burning in southern California on 09 August 2018. This comparison demonstrates how fire detection can be affected by both satellite viewing angle and shortwave infrared detector spatial resolution (4 km at satellite sub-point for the GOES-14/15 Imager, vs 2 km for the GOES-16/17 ABI).

On the previous day, a 30-meter resolution Landsat-8 False Color Red-Green-Blue (RGB) image visualized using RealEarth (below) provided a more detailed view of the Holy Fire, showing active fires (brighter red) around the northern and eastern perimeter of the burn scar and the smoke plume that was drifting to the north and northwest.

Landsat-8 False Color image [click to enlarge]

Landsat-8 False Color RGB image [click to enlarge]

Smoke from Mendocino Complex fires in California

August 4th, 2018 |

GOES-16

GOES-16 “Red” Visible (0.64 µm, left) and Shortwave Infrared (3.9 µm, right) images, with hourly plots of surface observations [click to play animation | MP4]

GOES-16 (GOES-East) “Red” Visible (0.64 µm) and Shortwave Infrared (3.9 µm) images (above) showed the smoke and thermal anomalies or “hot spots” (red pixels) associated with the Mendocino Complex burning in Northern California on 04 August 2018. Smoke was reducing the surface visibility to 2.5 miles at nearby Sacramento International Airport KSMF and Marysville KMYV. As of 7pm local time on 04 August the Mendocino Complex had burned 229,000 acres.

A 30-meter resolution Landsat-8 False Color Red-Green-Blue (RGB) image viewed using RealEarth (below) showed active burning along the eastern edge of the Ranch Fire (part of the Mendocino Complex) at 1845 UTC. The larger fire was producing a pyrocumulus cloud in addition to the dense smoke plume drifting northeastward.

Landsat-8 False Color image [click to enlarge]

Landsat-8 False Color RGB image [click to enlarge]

GOES-16 Upper-level (6.2 µm), Mid-level (6.9 µm) and Low-level (7.3 µm) Water Vapor images (below) revealed a southwest-to-northeast oriented band of moisture and fast flow associated with a middle to upper-tropospheric jet streak that was moving over the region (300 hPa analyses). “Red” Visible (0.64 µm) images showed the smoke plume drifting rapidly northeastward over California and Nevada, and visible Derived Motion Winds — which are calculated for pressure levels at and below 700 hPa —  tracked the smoke moving as fast as 58 knots at 2337 UTC. This speed was faster than 00 UTC winds at or below 700 hPa on rawinsonde data from either Oakland KOAK or Reno KREV.

GOES-16 Upper-level (6.2 µm, top left), Mid-level (6.9 µm, top right), Low-level (7.3 µm, bottom left) Water Vapor and "Red" Visible with Derived Motion Winds (0.64 µm, bottom right) [click to play MP4 animation]

GOES-16 Upper-level (6.2 µm, top left), Mid-level (6.9 µm, top right), Low-level (7.3 µm, bottom left) Water Vapor images and “Red” Visible (0.64 µm, bottom right) images with Derived Motion Winds [click to play MP4 animation]

===== 07 August Update =====

NOAA-20 VIIRS Day/Night Band (0.7 µm), Near-Infrared (1.61 µm and 2.25 µm) and Shortwave Infrared (3.75 µm) images [click to enlarge]

NOAA-20 VIIRS Day/Night Band (0.7 µm), Near-Infrared (1.61 µm and 2.25 µm) and Shortwave Infrared (3.75 µm) images [click to enlarge]

A comparison of NOAA-20 VIIRS Day/Night Band (0.7 µm), Near-Infrared (1.61 µm and 2.25 µm) and Shortwave Infrared (3.75 µm) images (above; courtesy of William Straka, CIMSS) showed the nighttime glow and thermal signatures of the Mendocino Complex fires on 07 August 2018. As of 8:30am the fire had burned over 290,000 acres, becoming the largest wildfire on record in the state of California.

 

Carr Fire pyrocumulonimbus in California

July 27th, 2018 |

GOES-16

GOES-16 “Red” Visible (0.64 µm, left) and Shortwave Infrared (3.9 µm, right) images [click to play MP4 animation]

1-minute Mesoscale Domain Sector GOES-16 (GOES-East) “Red” Visible (0.64 µm) and Shortwave Infrared (3.9 µm) images (above) showed the large thermal anomaly or “hot spot” (cluster of red pixels) associated with the Carr Fire in northern California as it produced a pyrocumulonimbus (pyroCb) cloud during the afternoon hours on 27 July 2018. A 30-meter resolution Landsat-8 False Color image from the previous day showed the large size of the burn scar; extreme fire behavior on 27 July caused the Carr Fire to quickly increase in size and move closer to Redding CA, and also produce the pyroCb.

Another view using GOES-16 “Red” Visible, Shortwave Infrared, “Clean” Infrared Window (10.3 µm) and the Cloud Top Temperature product (below) showed the pyroCb cloud as it drifted rapidly northeast over Nevada and Oregon, along with a second (albeit smaller) pyroCb cloud which developed around 0130 UTC. One standard parameter used for defining a pyroCb cloud is a minimum cloud-top longwave infrared brightness temperature of -40ºC (ensuring complete glaciation) — and in this case with 1-minute imagery, the multi-spectral Cloud Top Temperature (CTT) product (FAQ) indicated that the pyroCb cloud reached the -40ºC threshold 19 minutes earlier than the 10.3 µm infrared imagery. From that point forward, the CTT product was consistently at least 5-10ºC colder than the 10.3 µm brightness temperature; the CTT product eventually displayed a minimum value of -53.9ºC over northeastern California. Even as the 10.3 µm brightness temperature began to rapidly warm after about 0100 UTC, the CTT product continued to display values in the -45 to -50ºC range (shades of green) which allowed for unambiguous tracking of the pyroCb.

GOES-16 "Red" Visible (0.64 µm, top left), Shortwave Infrared (3.9 µm, top right), "Clean" Infrared Window (10.3 µm, bottom left) and Cloud Top Temperature product (bottom right) [click to play MP4 animation]

GOES-16 “Red” Visible (0.64 µm, top left), Shortwave Infrared (3.9 µm, top right), “Clean” Infrared Window (10.3 µm, bottom left) and Cloud Top Temperature product (bottom right) [click to play MP4 animation]

In the case of the second (smaller) pyroCb cloud that formed from the Carr Fire after 0130 UTC, the 10.3 µm brightness temperature failed to reach the -40ºC threshold, while the CTT product again displayed values in the -45 to -50ºC range. The coldest CTT value of -53.9ºC (seen with the initial pyroCb) roughly corresponded to an altitude of 12.5 km or 41,000 feet according to 00 UTC rawinsonde data from Reno, Nevada (below). Strong upper-tropospheric winds of 80-90 knots rapidly transported the pyroCb anvil northeastward.

Plot of 00 UTC rawinsonde data from Reno, Nevada [click to enlarge]

Plot of 00 UTC rawinsonde data from Reno, Nevada [click to enlarge]

Cranston Fire pyrocumulonimbus

July 25th, 2018 |

GOES-16

GOES-16 “Red” Visible (0.64 µm, left) and Shortwave Infrared (3.9 µm, right) images, with hourly plots of surface reports [click to play animation | MP4]

GOES-16 (GOES-East) “Red” Visible (0.64 µm) and Shortwave Infrared (3.9 µm) images (above) showed the smoke and pyrocumulus clouds as well as the thermal anomaly or “hot spot” (red pixels) associated with the Cranston Fire — located in the center of the images — which started southwest of Palm Springs, California (KPSP) around 1852 UTC or 11:52 am PDT on 25 July 2018. The large areas of red seen on the Shortwave Infrared images early in the animation were signatures of very hot sandy soil surfaces of the southern California deserts. Note the very warm air temperatures seen across the region; Palm Springs had an afternoon high of 116ºF, and Thermal KTRM had a high of 119ºF (farther inland, Death Valley had a high of 127ºF).

A slightly different view — with the fire located in the lower left corner, southwest of KPSP — using GOES-16 “Red” Visible (0.64 µm), Shortwave Infrared (3.9 µm) and “Clean” Infrared Window (10.3 µm) images (below) revealed that the fire actually produced 3 distinct pulses of pyroCumulonimbus (pyroCb) cloud, where the 10.3 µm cloud-top infrared brightness temperature reached or exceeded the -40ºC threshold (lime green enhancement). Three specific times that these separate pyroCb clouds were evident were 2102 UTC, 2147 UTC and 2312 UTC.

GOES-16 "Red" Visible (0.64 µm, left), Shortwave Infrared (3.9 µm, center) and "Clean" Infrared Window (10.3) images, with 4-letter airport identifiers plotted in yellow [click to play animation | MP4]

GOES-16 “Red” Visible (0.64 µm, left), Shortwave Infrared (3.9 µm, center) and “Clean” Infrared Window (10.3 µm, right) images, with 4-letter airport identifiers plotted in yellow [click to play animation | MP4]

Another view of the pyroCb pulses was provided by a 4-panel view of GOES-16 “Red” Visible (0.64 µm), Shortwave Infrared (3.9 µm), “Clean” Infrared Window (10.3 µm) and Cloud Top Phase (below). The coldest 10.3 µm cloud-top infrared brightness temperatures were -55ºC as the primary pyroCb anvil drifted northeastward toward the California/Nevada border.

GOES-16 "Red" Visible (0.64 µm, top left), Shortwave Infrared (3.9 µm, top right), "Clean" Infrared Window (10.3 µm, bottom left) and Cloud Top Phase (bottom right) images [click to play animation | MP4]

GOES-16 “Red” Visible (0.64 µm, top left), Shortwave Infrared (3.9 µm, top right), “Clean” Infrared Window (10.3 µm, bottom left) and Cloud Top Phase (bottom right) images [click to play animation | MP4]

There was also substantial lightning observed with these pyroCb clouds:


Below is a timelapse video of the first 8 hours of the fire, which shows the pyroCb evolution at the end.

Timelapse of Cranston Fire [click to play YouTube video]

Timelapse of Cranston Fire [click to play YouTube video]

===== 26 July Update =====

GOES-16 "Red" Visible (0.64 µm, top left), Shortwave Infrared (3.9 µm, top right), "Clean" Infrared Window (10.3 µm, bottom left) and Fire Temperature (bottom right) images [click to play animation | MP4]

GOES-16 “Red” Visible (0.64 µm, top left), Shortwave Infrared (3.9 µm, top right), “Clean” Infrared Window (10.3 µm, bottom left) and Fire Temperature (bottom right) images [click to play animation | MP4]

Another pyroCb was produced by the Cranston Fire on 26 July, as shown by GOES-16 “Red” Visible (0.64 µm), Shortwave Infrared (3.9 µm), “Clean” Infrared Window (10.3 µm) and Fire Temperature images (above). Similar to the previous day, there appeared to be 2 pulses of pyroCb formation — with cloud-top infrared brightness temperatures cooling to -44ºC. Pyrocumulus from the smaller Ribbon Fire (just southeast of the Cranston Fire) could also be seen.