Geostationary Lightning Mapper (GLM) data displayed with Geo2Grid

January 30th, 2021 |

GOES-16 ABI CONUS sector band 13 (Clean Window, 10.3 µm) infrared imagery, 1901-2001 UTC on 30 January 2021

Geo2Grid is a scripting tool that accesses various Python packages to display Geostationary Satellite data, described on this blog before here, here and here (Polar2Grid is a similar package for Low Earth Orbit satellite data).  The animation above shows GOES-16 Band-13 (Clean Window, 10.3 µm) infrared data for an hour over Oklahoma/Kansas/Missouri/Arkansas during a time when tornadoes occurred (imagery was produced using Geo2Grid and GOES-16 level-1b radiance files).  (SPC Storm Reports).

Gridded GLM data are available at this website;  both CONUS and Full Disk domains are available, CONUS data are a simple subset of the Full Disk imagery.  These netCDF files (with ‘GLMC’ in the filename) are available each minute, and contain a variety of gridded GLM products, some of which as distributed to National Weather Service forecast offices. By using the ‘glm_l2’ reader in Geo2Grid, data can be plotted, and subsequently overlain on top of the ABI imagery, as shown below.

GOES-16 ABI CONUS sector band 13 (Clean Window, 10.3 µm) infrared imagery, 1901-2001 UTC on 30 January 2021, overlain with GLM Total Optical Energy at 1-minute time steps (Click to animate)

Heavy rainfall and snowfall in Southern California

January 23rd, 2021 |

GOES-17 Air Mass RGB images, with contours of PV1.5 pressure [click to play animation | MP4]

GOES-17 Air Mass RGB images, with contours of PV1.5 pressure [click to play animation | MP4]

As an anomalously-deep 500 hPa low began to move inland over Southern California during the 23 January24 January 2021 period, GOES-17 (GOES-West)  Air Mass RGB images (above) showed a compact Potential Vorticity (PV) anomaly approaching the coast — and the RAP40 model indicated that the “dynamic tropopause” (defined here as the pressure of the PV1.5 surface) was descending to the 675 hPa pressure level at 18 UTC.

A west-to-east oriented cross section of RAP40 model fields along Line A-A’ (below) depicted the descending dynamic tropopause at 19 UTC.

Cross section of RAP40 model fields along line A-A' [click to enlarge]

Cross section of RAP40 model fields along line A-A’ [click to enlarge]

GOES-17 Mid-level Water Vapor (6.9 µm) images (below) showed the increasing reports of rain and snow that resulted as the PV Anomaly moved inland and provided additional forcing for ascent. Near the coast, thunderstorms were reported at Fulton and Long Beach around 03 UTC. Storm total precipitation amounts included rainfall of 1.40 inch and snowfall of 12-18 inches.

GOES-17 Mid-level Water Vapor (6.9 µm) images, with plots of hourly surface weather type [click to play animation | MP4]

GOES-17 Mid-level Water Vapor (6.9 µm) images, with plots of hourly surface weather type [click to play animation | MP4]

GOES-17 Water Vapor images at 2301 UTC and 0246 UTC (below) revealed sporadic lightning activity (indicated by small clusters of GLM Groups).

GOES-17 Mid-level Water Vapor (6.9 µm) image at 2301 UTC, with GLM Groups plotted in red [click to enlarge]

GOES-17 Mid-level Water Vapor (6.9 µm) image at 2301 UTC, with GLM Groups plotted in red [click to enlarge]

GOES-17 Mid-level Water Vapor (6.9 µm) image at 0246 UTC, with GLM Groups plotted in red [click to enlarge]

GOES-17 Mid-level Water Vapor (6.9 µm) image at 0246 UTC, with GLM Groups plotted in red [click to enlarge]

===== 24 January Update =====

GOES-17 Day Snow-Fog RGB images [click t play animation | MP4]

GOES-17 Day Snow-Fog RGB images [click to play animation | MP4]

On the following day, as clouds began to clear the areal extent of resulting fresh snow cover (darker shades of red) was seen in GOES-17 Day Snow-Fog RGB images (above). Even parts of the high desert — north and east of the mountain ranges — received some snowfall (for example, 2-3 inches were reported at Hesperia).

Suomi NPP VIIRS True Color RGB and False Color RGB images (below) showed the snow cover (shades of cyan) at 2036 UTC.

Suomi NPP VIIRS True Color RGB and False Color RGB images [click to enlarge]

Suomi NPP VIIRS True Color RGB and False Color RGB images [click to enlarge]

Tropical Storm Eta over the Gulf of Mexico

November 10th, 2020 |

Suomi NPP VIIRS Infrared Window (11.45 µm) and Day/Night Band (0.7 µm) images at 0734 UTC [click to enlarge]

Suomi NPP VIIRS Infrared Window (11.45 µm) and Day/Night Band (0.7 µm) images at 0734 UTC [click to enlarge]

A toggle between Suomi NPP VIIRS Infrared Window (11.45 µm) and Day/Night Band (0.7 µm) images at 0734 UTC (above) showed Tropical Storm Eta over the Gulf of Mexico (northwest of Cuba) on 10 November 2020. A large convective burst was seen southeast of the storm center, with concentric cloud-top gravity waves propagating radially outward from its lightning-illuminated core (intense lightning activity was causing the cluster of bright pixels on the Day/Night Band image).

1-minute Mesoscale Domain Sector GOES-16 (GOES-East) “Clean” Infrared Window (10.35 µm), GLM Flash Extent Density and “Red” Visible (0.64 µm) images (below) showed Tropical Storm Eta from sunrise to sunset, as it continued a slow northward movement — pulsing overshooting tops occasionally exhibited infrared brightness temperatures of -90ºC and colder (yellow pixels embedded within darker shades of purple), and lightning activity persisted for much of the day.

GOES-16 “Clean” Infrared Window (10.35 µm) images (with and without an overlay of GLM Flash Extent Density) and “Red” Visible (0.64 µm) images [click to play MP4 animation]

GOES-16 “Clean” Infrared Window (10.35 µm) images (with and without an overlay of GLM Flash Extent Density) and “Red” Visible (0.64 µm) images [click to play MP4 animation]

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

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

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

Eta once again reached Hurricane intensity at 1235 UTC on 11 November, as it approached the west coast of Florida. 1-minute GOES-16 Visible images (above) showed the partially exposed low-level circulation of Eta; however, it then weakened back to a Tropical Storm several hours later, at 1800 UTC.

Hurricane Eta in the Caribbean Sea

November 2nd, 2020 |

GOES-16 “Clean” Infrared Window (10.35 µm) images (with and without an overlay of GLM Flash Extent Density) and “Red” Visible (0.64 µm) images [click to play animation | MP4]

GOES-16 “Clean” Infrared Window (10.35 µm) images (with and without an overlay of GLM Flash Extent Density) and “Red” Visible (0.64 µm) images [click to play animation | MP4]

1-minute Mesoscale Domain Sector GOES-16 (GOES-East) “Clean” Infrared Window (10.35 µm), GLM Flash Extent Density and “Red” Visible (0.64 µm) images (above) showed Hurricane Eta as it was rapidly intensifying from a Category 2 to a Category 4 storm on 02 November 2020. For a few hours there was notable lightning activity within the inner eyewall of Eta.

GOES-16 Longwave Infrared (11.2 µm) images, with contours of 02 UTC deep-layer wind shear from the CIMSS Tropical Cyclones site (below) showed that the hurricane was moving through an environment of low shear, which favored intensification.

GOES-16 Longwave Infrared (11.2 µm) images, with contours of 18 UTC deep-layer wind shear [click to enlarge]

GOES-16 Longwave Infrared (11.2 µm) images, with contours of 02 UTC deep-layer wind shear [click to enlarge]

GOES-16 Infrared – Water Vapor Brightness Temperature Difference images (below) indicated that cloud tops within much of the central dense overcast surrounding the eye were likely above the local tropopause.

GOES-16 Infrared - Water Vapor Difference images [click to enlarge]

GOES-16 Infrared – Water Vapor Difference images [click to enlarge]

===== 03 November Update =====

NOAA-20 VIIRS Day/Night Band (0.7 µm) and Infrared Window (11.45 µm) images (credit: William Straka, CIMSS) [click to enlarge]

NOAA-20 VIIRS Day/Night Band (0.7 µm) and Infrared Window (11.45 µm) images (credit: William Straka, CIMSS) [click to enlarge]

A toggle between NOAA-20 VIIRS Day/Night Band (0.7 µm) and Infrared Window (11.45 µm) images (above) displayed Eta at 0729 UTC. Illumination from the Moon — in the Waning Gibbous phase, at 93% of Full — provided a distinct visible image at night.

Eta made landfall along the Caribbean coast of Nicaragua as a Category 4 hurricane around 2100 UTC;1-minute GOES-16 Infrared and Visible images during the period 1000-2100 UTC (below) showed that the overall appearance of Eta had deteriorated somewhat compared to the previous day, with warming cloud-top infrared brightness temperatures and a cloud-filled eye. There was no GOES-16 GLM-detected lightning activity during those 11 hours leading up to landfall.

GOES-16 “Clean” Infrared Window (10.35 µm) and “Red” Visible (0.64 µm) images [click to play animation | MP4]

GOES-16 “Clean” Infrared Window (10.35 µm) and “Red” Visible (0.64 µm) images [click to play animation | MP4]