Severe weather outbreak across the central US

March 28th, 2020 |

GOES- 16

GOES- 16 “Red” Visible (0.64 µm) images, with time-matched (+/- 4 minutes) SPC Storm Reports plotted in red [click to play animation | MP4]

1-minute Mesoscale Domain Sector GOES- 16 (GOES-East) “Red” Visible (0.64 µm) images (above) showed widespread events of severe weather (SPC Storm Reports) associated with a large occluding low pressure system and its frontal boundaries on 28 March 2020.

The corresponding GOES-16 “Clean” Infrared Window (10.35 µm) images are shown below. The coldest cloud-top infrared brightness temperatures were in the -60 to -70ºC range (red to black enhancement). The most significant tornado produced EF-3 damage as it moved through Jonesboro, Arkansas beginning at 2157 UTC.

GOES- 16 "Clean" Infrared Window (10.35 µm) images, with time-matched SPC Storm Reports plotted in purple [click to play animation | MP4]

GOES- 16 “Clean” Infrared Window (10.35 µm) images, with time-matched (+/- 4 minutes) SPC Storm Reports plotted in purple [click to play animation | MP4]

A toggle between a Suomi NPP VIIRS Visible (0.64 µm) image (with plots of available NUCAPS soundings) and the Gridded NUCAPS CAPE values (below) revealed pockets of instability across the lower Mississippi River Valley in advance of the approaching cold front. Due to the presence of dense multi-layer cloudiness across much of Arkansas, there were no successful infrared+microwave (green) NUCAPS profiles available near Jonesboro (KJBR), except for a few microwave-only (yellow) soundings just to the south.

Suomi NPP VIIRS Visible (0.64 µm) image with plots of available NUCAPS soundings + Gridded NUCAPS CAPE [click to enlarge]

Suomi NPP VIIRS Visible (0.64 µm) image with plots of available NUCAPS soundings + Gridded NUCAPS CAPE [click to enlarge]

A plot of 19 UTC rawinsonde data from Little Rock, Arkansas (below) indicated a CAPE value of 2836 J/kg.

Plot of 19 UTC rawinsonde data from Little Rock, Arkansas [click to enlarge]

Plot of 19 UTC rawinsonde data from Little Rock, Arkansas [click to enlarge]

Additional imagery of this event is available on the Satellite Liaison Blog.

Exploring the effect of parallax

January 10th, 2020 |

GOES-16 "Red" Visible (0.64 µm) images, including plot of SPC Storm Reports (with and without parallax correction) [click to play animation]

GOES-16 “Red” Visible (0.64 µm) images, including plot of SPC Storm Reports (with and without parallax correction) [click to play animation]

Overlapping 1-minute GOES-16 (GOES-East) Mesoscale Domain Sectors provided images at 30-second intervals over the Kansas/Missouri/Oklahoma/Arkansas area on 10 January 2019 — and “Red” Visible (0.64 µm) images (above) included plots of SPC Storm Reports (with and without parallax correction) during the time period which produced the first 2 tornadoes (1 in southwestern Missouri, and 1 in northeastern Oklahoma) of a large-scale severe weather outbreak that continued into the subsequent nighttime hours and the following day.

The GOES-16 Visible images for the times corresponding to the 2 tornado reports (below) include “parallax-corrected” — shifted upward to match a 13 km cloud top, the Maximum Parcel Level calculated from the 18 UTC Springfield, Missouri sounding — and actual surface locations for each report. For the Oklahoma tornado report, the parallax-corrected location more closely matches the location of overshooting tops; for the Missouri tornado report, the parallax-corrected location more closely matches the location where a cluster of overshooting tops had passed several minutes earlier.

GOES-16 "Red" Visible (0.64 µm) image at 2030 UTC, including plot of SPC Storm Reports (with and without parallax correction) [click to enlarge]

GOES-16 “Red” Visible (0.64 µm) image at 2030 UTC, including a Tornado report in Missouri (with and without parallax correction) [click to enlarge]

GOES-16 "Red" Visible (0.64 µm) image at 2051 UTC, including plot of Tornado report (with and without parallax correction) [click to enlarge]

GOES-16 “Red” Visible (0.64 µm) image at 2051 UTC, including a Tornado report in Oklahoma (with and without parallax correction) [click to enlarge]

GOES-16 parallax direction vectors and magnitude (km) for a cloud top feature at 50,000 feet (or 15.2 km) are shown below for select locations across the GOES-16 CONUS domain — a webapp that displays a current infrared image with user-selectable cloud heights is available here. Circled is a vector and magnitude in an area close to that shown in the images above.  Note: the length of the vectors does not correspond to the actual distance of parallax correction.

GOES-16 parallax direction vectors and magnitude (km) for a cloud top feature at 15 km [click to enlarge]

GOES-16 parallax direction vectors and magnitude (km) for a cloud top feature at 50,000 feet (15.2 km) [click to enlarge]

Similar webapps are available for the GOES-16 Full Disk, GOES-17 CONUS and GOES-17 Full Disk sectors.

GOES-17 parallax correction direction vectors and magnitude (km) for a cloud top feature at 50,000 feet (15.2 km) [click to enlarge]

GOES-17 parallax direction vectors and magnitude (km) for a cloud top feature at 50,000 feet (15.2 km) [click to enlarge]

Severe weather across the Deep South

December 16th, 2019 |

GOES-16

GOES-16 “Red” Visible (0.64 µm), with SPC Storm Reports plotted in red [click to play animation | MP4]

1-minute Mesoscale Domain Sector GOES-16 (GOES-East) “Red” Visible (0.64 µm) images (above) showed thunderstorms that produced a variety of severe weather (SPC Storm Reports) across the Deep South on 16 December 2019. Numerous overshooting tops could be seen with these storms.

GOES-16 “Clean” Infrared Window (10.35 µm) images (below) indicated that many of the overshooting tops exhibited brightness temperatures as cold as -70ºC (darker black pixels) — which closely corresponded to the Most Unstable air parcel Maximum Parcel Level (MU MPL) calculated from 21 UTC rawinsonde data from Jackson, Mississippi.

GOES-16 "Clean" Infrared Window (10.35 um), with SPC Storm Reports plotted in cyan [click to play animation | MP4]

GOES-16 “Clean” Infrared Window (10.35 µm), with SPC Storm Reports plotted in cyan [click to play animation | MP4]

Severe thunderstorms in the southern US

October 20th, 2019 |

GOES-16 “Clean” Infrared Window (10.35 µm) images, with SPC Storm Reports plotted in cyan [click to play animation | MP4]

GOES-16 “Clean” Infrared Window (10.35 µm) images, with SPC Storm Reports plotted in cyan [click to play animation | MP4]

1-minute Mesoscale Domain Sector GOES-16 (GOES-East) “Clean” Infrared Window (10.35 µm) images (above) showed thunderstorms that produced tornadoes, large hail and damaging winds (SPC storm reports) in the Dallas/Fort Worth, Texas area after sunset on 20 October 2019. One of the tornadoes produced EF-3 damage in North Dallas.

In a larger-scale view of GOES-16 Infrared images (below), other thunderstorms were seen that produced a variety of severe weather in other parts of Texas, Louisiana, Oklahoma, Arkansas and Missouri — including winds of 82 mph in Oklahoma and 80 mph in Arkansas. The rapidly-pulsing behavior of overshooting tops was well captured by the 1-minute imagery.

GOES-16 “Clean” Infrared Window (10.35 µm) images, with SPC Storm Reports plotted in white [click to play animation | MP4]

GOES-16 “Clean” Infrared Window (10.35 µm) images, with SPC Storm Reports plotted in white [click to play animation | MP4]