Wildfires in Southern California

December 3rd, 2020 |

GOES-17 “Red” Visible (0.64 µm) and Shortwave Infrared (3.9 µm) images [click to play animation | MP4]

GOES-17 “Red” Visible (0.64 µm) and Shortwave Infrared (3.9 µm) images [click to play animation | MP4]

As discussed on the Satellite Liaison Blog, wildfires driven by strong Santa Ana winds developed after sunset on 02 December — and 1-minute Mesoscale Domain Sector GOES-17 (GOES-West) “Red” Visible (0.64 µm) and Shortwave Infrared (3.9 µm) images (above) displayed the thermal anomalies and smoke plumes associated with larger fires that persisted into the subsequent daytime hours on 03 December 2020.

GOES-17 True Color Red-Green-Blue (RGB) images created using Geo2Grid (below) showed the offshore transport of wildfire smoke during the day.

 GOES-17 True Color RGB images [click to play animation | MP4]

GOES-17 True Color RGB images [click to play animation | MP4]

A before (24 November) / after (03 December) comparison of 30-meter resolution Landsat-8 False Color RGB images viewed using RealEarth (below) revealed the appearance of burn scars (darker shades of brown), active fire fronts (brighter shades of pink) and smoke plumes (shades of gray) associated with the Bond Fire east of Santa Ana and the smaller Airport Fire northwest of Corona.

Landsat-8 False Color images, 24 November vs 03 December 2020 [click to enlarge]

Landsat-8 False Color RGB images, 24 November vs 03 December 2020 [click to enlarge]

River Flooding in Southwest Alaska

May 5th, 2020 |

Landsat-8 False Color RGB mage + Google Maps background [click to enlarge]

Landsat-8 False Color RGB image + Google Maps background [click to enlarge]

A Landsat-8 False Color Red-Green-Blue (RGB) image as viewed using RealEarth (above) showed areas of flooding (water = darker shades of blue) along portions of the Innoko River and the Iditarod River in Southwest Alaska on 05 May 2020. Much of southwestern Alaska had received above-average winter season snowfall — and rapid snow melt was contributing to this river flooding.

The Suomi NPP VIIRS River Flood Areal Extent product over that same region (below) indicated several areas of 81-90% flooding coverage (red enhancement).

Suomi NPP VIIRS River Flood Areal Extent product [click to enlarge]

Suomi NPP VIIRS River Flood Areal Extent product [click to enlarge]

Developing winter storm over Colorado

March 19th, 2020 |

GOES-16 Mid-level Water Vapor (6.9 um) images, with hourly plots of surface wind barbs and gusts (knots) [click to play animation | MP4]

GOES-16 Mid-level Water Vapor (6.9 um) images, with hourly plots of surface wind barbs and gusts (knots) [click to play animation | MP4]

As a winter storm began to organize over Colorado on 19 March 2020, GOES-16 (GOES-East) Mid-level Water Vapor (6.9 um) images (above) showed the developing  middle tropospheric cyclonic circulation across the Colorado/Kansas/Nebraska border area. Peak wind gusts included 60 mph in Colorado and Nebraska, and 62 mph in Kansas (WPC Storm Summary).

As a result of the strong winds, several areas of blowing dust were seen in GOES-16 “Red” Visible (0.64 um), Split Window Difference (10.3-12.3 um) and Dust Red-Green-Blue (RGB) images (below): (1) a well-defined plume that originated in southeastern Colorado and moved northeastward across western Kansas, (2) a smaller plume originating north/northwest of Lamar, Colorado which moved eastward toward the Colorado/Kansas border, (3) a small plume that originated over the burn scar from the 07 March “Beaver Fire” in the Oklahoma Panhandle, and (4) multiple narrow plumes of dust in the wake of a cold front that moved southeastward across the region late in the day (which reduced the surface visiblity to 2 miles in southwestern Kansas).

GOES-16

GOES-16 “Red” Visible (0.64 um), Split Window Difference (10.3-12.3 um) and Dust RGB images [click to play animation | MP4]

A NOAA-20 True Color RGB image as viewed using RealEarth (below) provided a more detailed view of the dust plume north of Lamar, Colorado as well as the longer plume which stretched from southeastern Colorado into western Kansas.

NOAA-20 True Color RGB image at 18:40 UTC [click to enlarge]

NOAA-20 True Color RGB image at 18:40 UTC [click to enlarge]

GOES-16 Visible images with plots of GLM Groups (below) revealed a few clusters of lightning associated with convective elements that were likely producing thundersnow across northeastern Colorado and near the Colorado/Nebraska border. Where warmer air was still present near the Colorado/Kansas border, a more longer-lived thunderstorm was producing rainfall at the surface.

GOES-16

GOES-16 “Red” Visible (0.64 um) images, with GLM Groups plotted in red and hourly surface weather type plotted in yellow [click to play animation | MP4]



===== 20 March Update =====

GOES-16 Day Cloud Phase Distinction RGB images [click to play animation | MP4]

GOES-16 Day Cloud Phase Distinction RGB images [click to play animation | MP4]

On the following day, GOES-16 Day Cloud Phase Distinction RGB images (above) showed the large swath of fresh snow cover (shades of green) produced by this storm as it moved northeastward across the Upper Midwest. Clouds persisted over much of eastern Colorado, masking the extent of the snow cover there.

===== 21 March Update =====

Landsat-8 False Color RGB image, with and without labels [click to enlarge]

Landsat-8 False Color RGB image at 1724 UTC, with and without labels [click to enlarge]

On 21 March, a decrease in cloudiness over eastern Colorado allowed much of the snow cover (shades of cyan) to be seen in a swath of 30-meter resolution Landsat-8 False Color imagery as viewed using RealEarth (above). The effects of terrain were evident, with a lack of snow cover seen in areas where downslope flow was prevalent during the winter storm.

The effect of snow cover on boundary layer cloud development

March 15th, 2020 |

GOES-16 Snow/Cloud Discrimination RGB images [click to play animation]

GOES-16 Snow/Cloud Discrimination RGB images, with hourly plots of surface wind barbs (knots) [click to play animation]

GOES-16 (GOES-East) “Snow/Cloud Discrimination” Red-Green-Blue (RGB) images (above) revealed a west-to-east oriented band of fresh snow cover (1-4 inches, shades of red) across central Illinois on 15 March 2020. With a low-level northeasterly flow of cold air across the region, boundary layer cumulus clouds began to develop as solar heating warmed the surface — but this cloud development was suppressed over deeper portions of the snow cover. These RGB images use “Red” Visible (0.64 µm) data as the Red component, and Near-Infrared “Snow/Ice” (1.61 µm) data as the Green and Blue components; bare ground appears as shades of cyan, with supercooled water droplet clouds appearing as brighter shades of white.

A sequence of VIIRS Snow/Cloud Discrimination RGB images from NOAA-20 and Suomi NPP (below) showed a closer look at the band of snow cover and its effect on modulating the afternoon development of cumulus clouds.

VIIRS Snow/Cloud Discrimination RGB images from NOAA-20 and Suomi NPP [click to enlarge]

VIIRS Snow/Cloud Discrimination RGB images from NOAA-20 and Suomi NPP [click to enlarge]

A 30-meter resolution Landsat-8 False Color RGB image viewed using RealEarth (below) provided a detailed view of the band of snow cover (shades of cyan) at 1622 UTC.

Landsat-8 False Color RGB image, with and without labels [click to enlarge]

Landsat-8 False Color RGB image, with and without labels [click to enlarge]