GOES-17 (GOES-West) Upper-level Water Vapor (6.2 µm), Mid-level Water Vapor (6.9 µm) and Air Mass RGB images (above) displayed the signature of dry, ozone-rich air associated with a Potential Vorticity (PV) anomaly approaching Baja California and Southern California on 05 November 2019. The “dynamic tropopause” — taken to be the pressure of the PV1.5 surface — descended to the 500 hPa level within this PV anomaly.

A GOES-17 Water Vapor image with plots of available NOAA-20 NUCAPS soundings (below) is labeled with sounding points within the core of the PV anomaly (Point 1) and within the core of the driest air (Point 2).

The NUCAPS sounding profiles for Point 1 and Point 2 are shown below. The middle/upper troposphere was quite dry at both locations.

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A sequence of 1-minute Mesoscale Domain Sector GOES-16 (GOES-East) images from all 16 of the ABI spectral bands during the period 1358-1406 UTC on 02 November 2019 (above) revealed signatures of the launch of an Antares rocket from the Wallops Flight Facility along the eastern shore of Virginia. The signature that was seen in all 16 spectral bands was that of the low-altitude rocket exhaust condensation cloud, which originated at the launch site then drifted northeastward over the Chincoteague area.

In addition, a thermal signature of air that was superheated by the rocket exhaust was evident in Shortwave Infrared (3.9 µm) and Water Vapor (6.2 µm, 6.9 µm and 7.3 µm) images — initially about 2-3 miles east-northeast of Chincoteague at 1401 UTC, and then about 50 miles due east of Wallops Island at 1402 UTC (below). Also apparent on the 1402 UTC Water Vapor images was the cooler signature of the low-altitude exhaust condensation cloud near Chincoteague.

An animation of 16-panel images displaying all of the GOES-16 ABI spectral bands is shown below.

Regarding the northeastward-moving low-altitude rocket exhaust condensation cloud, GOES-16 Cloud Top Temperature and Cloud Top Phase products (above) indicated that the feature was composed of water droplets, exhibiting cloud top temperature values in the 8ºC to 10ºC range. According to 12 UTC rawinsonde data from Wallops Flight Facility, Virginia (below), those temperatures existed at altitudes of 1.8-2.1 km (5900-6900 ft) where there were southwesterly winds of 18-25 knots.

Because of the low early-morning sun angle, the exhaust condensation cloud was casting a shadow farther inland over Virginia, as seen in GOES-16 Visible images (below).

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As northeast Santa Ana winds began to increase before sunrise on 30 October 2019, 1-minute Mesoscale Domain Sector GOES-17 (GOES-West) Shortwave Infrared (3.9 µm) and “Red” Visible (0.64 µm) images (above) showed the sudden onset of a thermal anomaly (cluster of  hot 3.9 µm pixels) — associated with the Easy Fire northwest of Los Angeles — which occurred at 1308-1309 UTC (6:08-6:09 AM local time). After sunrise, the narrow wind-driven smoke plume was seen in the Visible imagery.

A comparison of 3 consecutive VIIRS Shortwave Infrared (3.74 µm) images from Suomi NPP and NOAA-20 with the corresponding GOES-17 Shortwave Infrared (3.9 µm) images (below) demonstrated the advantage of polar orbiter imagery for providing a more accurate depiction of the size and location of a fire. Note: the color enhancements are different for the Suomi NPP/NOAA-20 vs GOES-17 images, since there are differences between shortwave infrared detectors on the VIIRS and ABI instruments.

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GOES-16 and GOES-17 satellite imagery can be remapped and combined to create stereoscopic imagery. To achieve the 3-dimensional effect, cross your eyes until three scenes are visible, and focus on the middle image.  You can also achieve this by placing a finger halfway between your eyes and the screen, and focusing on your finger, then focusing on the image behind.  (Here’s a website that might help).  The imagery above, from 24 October 2019, shows high clouds rotating anti-cyclonically above the smoke produced from the Kincade Fire (previous blog posts on this fire are here and here). The smoke plume extended far out into the Pacific Ocean. A Full-resolution image animation is shown below.

Animations for 25 October, 26 October, 27 October, 28 October and 29 October are shown below, in order.

On the 25th and 26th of October, prevailing winds moved smoke into the Bay Area.  On both days, the fire appeared less vigorous in the visible imagery than on the 24th, at top, or on the 27th;  at least, it appeared to be producing less smoke.

On the 27th, below, the fire resembled the scene on 24 October, with a large smoke plume extending far southwest into the Pacific Ocean.

On the 28th, below, smoke generation has decreased, and the smoke pall appears over the Bay Area again. A full-resolution version is available here.

The scene on the 29th, below (Full resolution available here) is shown below. The smoke plume is extensive.

How did the smoke plume change from day to day? The animation below shows data at 2350 UTC on 24-29 October.

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