Camp Fire in northern California

November 8th, 2018 |

GOES-16

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) [click to play animation | MP4]

The Camp Fire started at 1433 UTC or 6:33 AM local time on 08 November 2018 in Northern California; the rapid spread of the fire prompted evacuations and forced road closures. GOES-16 (GOES-East) GOES-16 “Red” Visible (0.64 µm), Shortwave Infrared (3.9 µm), “Clean” Infrared Window (10.3 µm) and Fire Temperature (above) showed the evolution of the fire at 5-minute intervals — especially noteworthy were the rapid vertical jump of the smoke column seen at 1547 UTC (which cast a long shadow), and Fire Temperature values that exceeded 2000 K (bright red pixels) at numerous times with a maximum value just over 2300 K.

A GOES-16 Mesoscale Domain Sector was positioned over California beginning at 2115 UTC, providing imagery at 1-minute intervals — a comparison of Visible and Shortwave Infrared images (below) showed how quickly the hot thermal signature of the fire (yellow to red enhancement) advanced southwestward during the remaining 3 hours of daylight. Just northwest of the fire, Chico (station identifier KCIC) reported very low relative humidity values (6% at 21 UTC), as seen by the large spread between temperature and dewpoint late in the day.

GOES-16

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

1-km resolution NOAA-18 AVHRR Visible (0.64 µm), Near-Infrared “Vegetation” (0.86 µm), Shortwave Infrared (3.7 µm) and Infrared Window (10.8 µm) images (below) showed the bifurcation of the smoke plume as well as the large, very hot thermal signature of the fire at 1712 UTC or 9:12 AM local time.

NOAA-18 AVHRR Visible (0.64 µm), Near-Infrared "Vegetation" (0.86 µm), Shortwave Infrared (3.7 µm) and Infrared Window (10.8 µµ) images [click to enlarge]

NOAA-18 AVHRR Visible (0.64 µm), Near-Infrared “Vegetation” (0.86 µm), Shortwave Infrared (3.7 µm) and Infrared Window (10.8 µm) images [click to enlarge]

NOAA-20 Visible (0.64 µm), Near-Infrared

NOAA-20 VIIRS Visible (0.64 µm), Near-Infrared “Snow/Ice” (1.61 µm) and Infrared Window (11.45 µm) images [click to enlarge]

Higher spatial resolution views were provided by NOAA-20 VIIRS Visible (0.64 µm), Near-Infrared “Snow/Ice” (1.61 µm) and Infrared Window (11.45 µm) images (above) and by Aqua MODIS Visible (0.65 µm), Near-Infrared “Snow/Ice” (1.61 µm) and Infrared Window (11.0 µm) images (below). [Note: the NOAA-20 VIIRS images are incorrectly labeled as Suomi NPP]

Aqua MODIS Visible (0.65 µm), Near-Infrared

Aqua MODIS Visible (0.65 µm), Near-Infrared “Snow/Ice” (1.61 µm) and Infrared Window (11.0 µm) images [click to enlarge]

Alternative views of the NOAA-20 VIIRS and Aqua MODIS images are shown below (using legacy AWIPS-1).They include Shortwave Infrared images from the 2 satellites, which reveal the very large (approximately 10 miles in length) thermal anomaly or fire “hot spot”. Due to the very dry atmosphere over the region (MODIS 6.7 µm Water Vapor image), the smoke could be clearly seen on the MODIS 1.37 µm Cirrus image (since there was very little attenuation of upwelling 1.37 µm radiation by middle/upper-tropospheric water vapor).

NOAA-20 Visible (0.64 µm), Day/Night Band (0.7 µm), Near-Infrared "Snow/Ice" (1.61 µm), Shortwave Infrared (3.74 µm) and Infrared Window (11.45 µm) images [click to enlarge]

NOAA-20 Visible (0.64 µm), Day/Night Band (0.7 µm), Near-Infrared “Snow/Ice” (1.61 µm), Shortwave Infrared (3.74 µm) and Infrared Window (11.45 µm) images [click to enlarge]

Aqua MODIS Visible (0.65 µm), Near-Infrared "Cirrus" (1.37 µm), Near-Infrared "Snow/Ice" (1.61 µm), Shortwave Infrared (3.7 µm) and Infrared Window (11.0 µm) images [click to enlarge]

Aqua MODIS Visible (0.65 µm), Near-Infrared “Cirrus” (1.37 µm), Near-Infrared “Snow/Ice” (1.61 µm), Shortwave Infrared (3.7 µm) and Infrared Window (11.0 µm) images [click to enlarge]

As a result of the unusual dryness air mass across the region, the 00 UTC Oakland sounding set a record low Total Precipitable Water value for the date (3 mm or 0.12 inch):

 

The Aqua MODIS Total Precipitable Water product at 2123 UTC (below) showed widespread values in the 3-5 mm range (darker shades of brown) over much or northern California. 12 hours later, the TPW value from the 12 UTC Oakland sounding was slightly lower (2.9 mm or 0.11 inch) — and the MODIS TPW product at 0921 UTC continued to show widespread dry air over California.

Aqua MODIS Total Precipitable Water product and Visible (0.65 µm) image at 2123 UTC [click to enlarge]

Aqua MODIS Total Precipitable Water product and Visible (0.65 µm) image at 2123 UTC [click to enlarge]

True Color Red-Green-Blue (RGB) imagery from NOAA-20 VIIRS (below) provided a good view of the smoke.

NOAA-20 VIIRS True Color RGB image [click to enlarge]

NOAA-20 VIIRS True Color RGB image [click to enlarge]

A NOAA-15 AVHRR Shortwave Infrared image at 0225 UTC or 6:25 PM local time (below) depicted the very large thermal anomaly of the fire.

NOAA-15 AVHRR Shortwave Infrared (3.7 µm) image; major highways are plotted in cyan, with Interstate highways plotted in red [click to enlarge]

NOAA-15 AVHRR Shortwave Infrared (3.7 µm) image; major highways are plotted in cyan, with Interstate highways plotted in red [click to enlarge]

The smoke had an adverse  impact on air quality over 100 miles from the fire source: the surface visibility dropped to 1 mile at Santa Rosa KSTS and 2 miles at San Francisco International Airport KSFO (below).

Time series of surface observations for Santa Rosa [click to enlarge]

Time series of surface observations from Santa Rosa [click to enlarge]

Time series of surface observations from San Francisco International Airport [click to enlarge]

Time series of surface observations from San Francisco International Airport [click to enlarge]

===== 09 November Update =====

NOAA-20 VIIRS Day/Night Band (0.7 µm) and Shortwave Infrared (3.74 µm) images [click to enlarge]

NOAA-20 VIIRS Day/Night Band (0.7 µm) and Shortwave Infrared (3.74 µm) images [click to enlarge]

Nighttime VIIRS Day/Night Band (0.7 µm) and Shortwave Infrared (3.74 µm) images from NOAA-20 at 0849 UTC (above) and Suomi NPP at 0942 UTC (below) revealed the bright glow and the large, hot thermal anomaly of the Camp Fire.

Suomi NPP VIIRS Day/Night Band (0.7 µm) and Shortwave Infrared (3.74 µm) images [click to enlarge]

Suomi NPP VIIRS Day/Night Band (0.7 µm) and Shortwave Infrared (3.74 µm) images [click to enlarge]

VIIRS True Color RGB images from Suomi NPP at 2104 UTC and NOAA-20 at 2154 UTC (below) showed the broad extent of the smoke from the Camp Fire in northern California as well as the Woolsey Fire in southern California. These images were captured and processed by the CIMSS/SSEC Direct Broadcast ground station.

Suomi NPP VIIRS True Color RGB image at 2104 UTC [click to enlarge]

Suomi NPP VIIRS True Color RGB image at 2104 UTC [click to enlarge]

NOAA-20 VIIRS True Color RGB image at 2154 UTC [click to enlarge]

NOAA-20 VIIRS True Color RGB image at 2154 UTC [click to enlarge]

An animation of 1-minute GOES-16 Visible and Shortwave Infrared images (below) revealed several plume jumps over the fire source from 15-19 UTC — and toward the end of the day, a decrease in the areal coverage and intensity of hot pixels indicated that extreme fire conditions were easing and containment efforts were slowing the spread of the fire.

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

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

Abnormally dry to extreme drought conditions across California were a contributing factor to this and other wildfires across the state.

US Drought Monitor conditions as of 06 November [click to enlarge]

US Drought Monitor conditions as of 06 November [click to enlarge]

====== 11 November Update =====

Suomi NPP VIIRS Shortwave Infrared (3.74 µm) images [click to play animation]

Suomi NPP VIIRS Shortwave Infrared (3.74 µm) images [click to play animation]

A sequence of Suomi NPP VIIRS Shortwave Infrared (3.74 µm) images centered at Paradise, California viewed using RealEarth (above) showed the spread of the Camp Fire thermal anomaly (dark black pixels) during the period 1943 UTC on 08 November to 1046 UTC on 11 November.

1-minute GOES-16 Visible and Shortwave Infrared images (below) showed the development of new smoke plume and hot thermal signatures around the periphery of the ongoing Camp Fire during the day on 11 November. As of 1849 UTC (10:49 AM local time), the fire had burned 109,000 acres and was listed as 25% contained.

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

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

The new smoke plume — as well as residual smoke from previous days of burning — could be seen on VIIRS True Color RGB imagery from Suomi NPP at 2029 UTC and NOAA-20 at 2114 UTC (below). The entire image swaths as captured and processed by the Direct Broadcast ground station at CIMSS/SSEC can be seen here and here.

Suomi NPP VIIRS True Color RGB image at 2029 UTC [click to enlarge]

Suomi NPP VIIRS True Color RGB image at 2029 UTC [click to enlarge]

NOAA-20 VIIRS True Color RGB image at 2114 UTC [click to enlarge]

NOAA-20 VIIRS True Color RGB image at 2114 UTC [click to enlarge]

The Camp Fire has claimed 42 lives and destroyed 6,522 homes and 260 businesses, making it both the deadliest and the most destructive wildfire on record for the state of California.

Fog/stratus dissipation in southern Louisiana

October 30th, 2018 |

GOES-16

GOES-16 “Red” Visible (0.64 µm) images [click to play animation | MP4]

The topic of a conversation on Twitter, GOES-16 (GOES-East) “Red” Visible (0.64 µm) images (above) revealed curious circular areas of fog/stratus dissipation across southern Louisiana on the morning of 30 October 2018. — making it a natural candidate for the “What the heck is this?” blog category.

GOES-16 GEOCAT Low IFR Probability and Fog/Low Stratus Depth products (below) indicated that this fog and low stratus had been increasing in coverage and spreading northward across Louisiana during the preceding nighttime hours (VIIRS fog/stratus Brightness Temperature Difference images) — and the fog/stratus was relatively shallow, only having a depth of about 300 feet or less. In fact, if you look closely at the Visible animation above, a few small spots of slightly brighter cloud can be seen in the vicinity of Baton Rouge KBTR which are tall objects (such as refinery stacks, and even the State Capitol building) protruding above the fog/stratus and acting as an obstacle to their flow.

GOES-16 Low Instrument Flight Rules (IFR) Probability [click to play animation | MP4]

GOES-16 Low Instrument Flight Rules (IFR) Probability [click to play animation | MP4]

GOES-16 Fog/Low Stratus Depth product [click to play animation | MP4]

GOES-16 Fog/Low Stratus Depth product [click to play animation | MP4]

A sequence of 4-panel comparisons of GOES-16 “Blue” Visible (0.47 µm), “Red” Visible (0.64 µm) and Near-Infrared “Vegetation” (0.86 µm) images with Near-Infrared “Snow/Ice” (1.61 µm), Near-Infrared “Cloud Particle Size” (2.24 µm) and Shortwave Infrared (3.9 µm) images (below) showed no indication of any substantial differences between the cloud material within the circular features and the adjacent fog/stratus. The largest “outer rings” of the dissipating fog/stratus areas had a small amount of vertical extent, which cast a shadow that was best seen in the Near-Infrared 0.86 µm and 1.61 µm images.

4-panel comparisons of GOES-16

Sequence of 4-panel comparisons of GOES-16 “Blue” Visible (0.47 µm), “Red” Visible (0.64 µm), Near-Infrared “Vegetation” (0.86 µm), “Snow/Ice” (1.61 µm), and “Cloud Particle Size” (2.24 µm), and Shortwave Infrared (3.9 µm) images [click to play animation | MP4]

The most plausible explanation for the circular dissipation features turned out to be fires that were set in sugar cane fields following harvest — particulates in the smoke could have “seeded” the fog/stratus cloud layer, either changing the particle size distribution or making the cloud more susceptible to faster dissipation after sunrise due to solar heating of black carbon nuclei within the cloud droplets.  An Aqua MODIS Shortwave Infrared (3.7 µm) image from the previous afternoon (below) did reveal a number of small thermal anomalies or fire “hot spots” (yellow to red pixels) across the region at 1909 UTC (2:09 PM local time).

Aqua MODIS Shortwave Infrared (3.7 µm) image [click to enlarge]

Aqua MODIS Shortwave Infrared (3.7 µm) image [click to enlarge]

Similarly, GOES-16 Shortwave Infrared images on 29 October (below) also showed signatures of widespread small and generally short-lived fires (darker black pixels) across southern Louisiana. Surface winds were very light across that area (KARA | KPTN | KNBG | KMSY | KNEW), minimizing smoke dispersion from any fires.

GOES-16 Shortwave Infrared (3.9 µm) images [click to play animation | MP4]

GOES-16 Shortwave Infrared (3.9 µm) images [click to play animation | MP4]

Pyrocumulonimbus cloud in South Africa

October 29th, 2018 |

Meteosat-11 Visible (0.8 µm), Shortwave Infrared (3.92 µm) and Longwave Infrared Window (10.8 µm) images [click to play animation | MP4]

Meteosat-11 Visible (0.8 µm, top), Shortwave Infrared (3.92 µm, center) and Longwave Infrared Window (10.8 µm, bottom) images [click to play animation | MP4]

The Garden Route Fires had been burning since about 24 October 2018 near George along the southern coast of South Africa (media story). On 29 October, EUMETSAT Meteosat-11 High Resolution Visible (0.8 µm), Shortwave Infrared (3.92 µm) and Longwave Infrared Window (10.8 µm) images (above) showed an elongated west-to-east oriented thermal anomaly or fire “hot spot” (red pixels) just northeast of George (station identifier FAGG) on Shortwave Infrared imagery during the hours leading up to the formation of a pyrocumulonimbus (pyroCb) cloud around 1300 UTC. The pyroCb exhibited the characteristic warm (+10 to +15ºC, darker gray enhancement) shortwave infrared cloud-top signature just off the coast at 1315 UTC, — this is due to enhanced solar reflection off ice crystals that are smaller compared to those of conventional thunderstorm tops.

Zooming out a bit to follow the southeastward drift of the pyroCb cloud (below), the coldest cloud-top 10.8 µm infrared brightness temperature (BT) was -61ºC (darker red enhancement) at 1315 UTC — then the cloud tops remained in the -55 to -59ºC range (orange enhancement) for the next 6 hours or so. Leveraging the large difference between cold 10.8 µm and warm 3.92 µm BTs, NRL calculates a pyroCb index, which classified this feature as an “intense pyroCb” (1315 UTC | animation). The coldest 10.8 µm cloud-top BT of -61ºC roughly corresponds to an altitude of 13.5 km based on 12 UTC rawinsonde data from Port Elizabeth (plot | list).

Meteosat-11 Shortwave Infrared (3.92 µm, left) and Longwave Infrared Window (10.8 µm, right) images [click to play animation | MP4]

Meteosat-11 Shortwave Infrared (3.92 µm, left) and Longwave Infrared Window (10.8 µm, right) images [click to play animation | MP4]

Imagery from NOAA-19 at 1420 UTC (courtesy of René Servranckx) also revealed the warm (dark gray) Shortwave Infrared pyroCb signature, along with a minimum cloud-top infrared BT of -58.1ºC (below).

NOAA-19 AVHRR imagery at 1420 UTC [click to enlarge]

NOAA-19 AVHRR imagery at 1420 UTC [click to enlarge]

A Suomi NPP VIIRS True Color Red-Green-Blue (RGB) image at 1230 UTC (below) was about a half hour before the formation of the pyroCb, but it did show a signature of smoke drifting southeastward off the coast.

Suomi NPP VIIRS True Color RGB image [click to enlarge]

Suomi NPP VIIRS True Color RGB image [click to enlarge]

On the following day (30 October), a NOAA-20 VIIRS True Color image (below) showed the classic comma cloud signature of a mid-latitude cyclone south of the coast, with the band of cold-frontal clouds extending northward across Lesotho. Note the thick plume of smoke spreading eastward within the strong post-frontal westerly winds.

NOAA-20 VIIRS True Color RGB image [click to enlarge]

NOAA-20 VIIRS True Color RGB image [click to enlarge]

A time series of of surface observations from George (below) supported the idea of a cold frontal passage: ahead of the front, temperatures rapidly rose to 104ºF/40ºC (with a dew point of 39ºF/4ºC) on 28 October about 1.5 hours prior to the formation of the pyroCb — then strong westerly winds (gusting to 40 knots/21 mps) with rising pressures and falling temperatures followed on 30 October.

Time series plot of of surface observations from George [click to enlarge]

Time series plot of of surface observations from George [click to enlarge]

The pyroCb research community believes that this is the first documented case of a pyroCb on the African continent.

 

Delta Fire pyroCumulonimbus cloud in California

September 5th, 2018 |

GOES-16

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 animation | MP4]

GOES-16 (GOES-East) “Red” Visible (0.64 µm), Shortwave Infrared (3.9 µm), “Clean” Infrared Window (10.3 µm) and Cloud Top Temperature product images displayed using AWIPS (above) showed the formation of a pyroCumulonimbus (pyroCb) cloud generated by the Delta Fire in Northern California late in the day on 05 September 2018. As the pyroCb cloud drifted eastward toward the California/Nevada border, Cloud Top Temperature values cooled to a minimum of -53ºC (lighter green enhancement) at 0300 UTC. Note the pulsing behavior of updrafts over the fire area: 2 distinct updraft pulses were apparent (at 0022 UTC and 0042 UTC), with the later pulse producing the pyroCb.



A longer animation of GOES-16 “Red” Visible, Shortwave Infrared and “Clean” Infrared Window images displayed using McIDAS (below) showed that the first hot (red) Shortwave Infrared pixels appeared at 2027 UTC. The fire caused a 5-mile section of Interstate 5 to be closed.

GOES-16 "Red" Visible (0.64 µm, top), Shortwave Infrared (3.9 µm, middle), "Clean" Infrared Window (10.3 µm, bottom); Interstate 5 is plotted in cyan [click to play animation | MP4]

GOES-16 “Red” Visible (0.64 µm, top), Shortwave Infrared (3.9 µm, middle) and “Clean” Infrared Window (10.3 µm, bottom) images; Interstate 5 is plotted in cyan [click to play animation | MP4]

GOES-17 (positioned at 89.5º W longitude during its post-launch checkout phase) had a more direct view of the pyroCb than GOES-16 (positioned over the Atlantic Ocean at 75.2º W longitude) — and GOES-17 “Red” Visible, Shortwave Infrared and “Clean” Infrared Window images are shown below. Unfortunately the default GOES-17 Western US Mesoscale Domain Sector was shifted farther to the south on this day, so 1-minute imagery of the pyroCb event was not available.

GOES-17 "Red" Visible (0.64 µm, top), Shortwave Infrared (3.9 µm, middle), "Clean" Infrared Window (10.3 µm, bottom) images; Interstate 5 is plotted in cyan [click to play animation | MP4]

GOES-17 “Red” Visible (0.64 µm, top), Shortwave Infrared (3.9 µm, middle) and “Clean” Infrared Window (10.3 µm, bottom) images; Interstate 5 is plotted in cyan [click to play animation | MP4]

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