Severe thunderstorms across Oklahoma, Kansas and Missouri

May 22nd, 2019 |

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

GOES-16 “Red” Visible (0.64 µm) images, 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 the development of supercell thunderstorms that produced tornadoes, large hail and damaging winds (SPC Storm Reports) across parts of Oklahoma, Kansas and Missouri on 22 May 2019.

GOES-16 “Clean” Infrared Window (10.35 µm) images (below) showed the storms as they persisted into the nighttime hours — including storms that produced EF3-rated tornadoes that affected Golden City, Missouri around 0211 UTC (which was responsible for 3 fatalities) and Jefferson City, Missouri around 0440 UTC.

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]

A closer look at 1-minute GOES-16 Infrared images for the storm producing the EF-3 tornado that affected Golden City, Missouri  is shown below. A pulsing updraft with cold (brighter white) infrared brightness temperature overshooting tops could be seen with the parent supercell as it crossed the Oklahoma/Kansas border around 0000 UTC, moved across extreme southeastern Kansas, then moved into southwestern Missouri around 0100 UTC. The NWS Springfield damage survey listed the start time of the Garden City tornado at 0151 UTC.

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]

About 20 minutes prior to the Jefferson City tornado, a Terra MODIS Infrared Window (11.0 µm) image (below) displayed a well-defined Enhanced-V storm top signature.

Terra MODIS Infrared Window (11.0 µm) image. with plot of SPC storm reports [click to enlarge]

Terra MODIS Infrared Window (11.0 µm) image, with plot of SPC storm reports [click to enlarge]

A closer look at 1-minute GOES-16 Infrared images for the storm producing the EF-3 tornado that affected Jefferson City (KJEF) is shown below — of note are the 2 pre-tornado updraft pulses west/southwest of KJEF at 0346 UTC and 0359 UTC, when cloud-top infrared brightness temperatures briefly cooled to -81ºC and -82ºC, respectively (violet pixels). The NWS St. Louis storm survey indicated that the tornado which eventually moved through Jefferson City began southwest of the city at 0420 UTC.

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]

A few hours later, a sequence of 3 VIIRS Infrared Window (11.45 µm) images (below) from Suomi NPP and NOAA-20 showed the line of supercell thunderstorms between 0704 and 0844 UTC.

VIIIRS Infrared Window (11.45 µm) images from Suomi NPP (0704 and 0844 UTC) and NOAA-20 (0754 UTC) [click to enlarge]

VIIRS Infrared Window (11.45 µm) images from Suomi NPP (0704 and 0844 UTC) and NOAA-20 (0754 UTC) [click to enlarge]

A closer view of the Suomi NPP VIIRS Infrared Window (11.45 µm) image at 0704 UTC (below) revealed another well defined Enhanced-V signature in far northeastern Oklahoma.

Suomi NPP VIIRS Infrared Window (11.45 µm) image at 0704 UTC [click to enlarge]

Suomi NPP VIIRS Infrared Window (11.45 µm) image at 0704 UTC [click to enlarge]

The Suomi NPP VIIRS Infrared Window (11.45 µm) image at 0844 UTC (below) depicted an example of a warm “moat” surrounding a cold overshooting top having a minimum infrared brightness temperature of -81ºC (violet enhancement) east of Patoka, Illinois.

Suomi NPP VIIRS Infrared Window (11.45 µm) image at 0844 UTC [click to enlarge]

Suomi NPP VIIRS Infrared Window (11.45 µm) image at 0844 UTC [click to enlarge]

Transport of Canadian wildfire smoke across the Northeast US

May 22nd, 2019 |

GOES-16 CIMSS Natural Color images, with an overlay of the Smoke Detection Product ;click to play animation | MP4]

GOES-16 CIMSS Natural Color RGB images, with an overlay of the Smoke Detection Product [click to play animation | MP4]

GOES-16 (GOES-East) CIMSS Natural Color Red-Green-Blue (RGB) images with an overlay of the Smoke Detection Product (above) revealed curved filaments of wildfire smoke moving southeastward across the Northeast US and the adjacent offshore waters of the Atlantic Ocean on 22 May 2019. The smoke filaments were classified as Medium/High confidence by the algorithm — additional information on GOES-R Aerosol Detection Products in AWIPS is available here and here.

During the preceding overnight hours, with ample illumination from the Moon (in the Waning Gibbous phase, at 92% of Full) smoke filaments were evident over the Atlantic Ocean on Suomi NPP VIIRS Day/Night Band (0.7 µm) imagery at 0722 UTC or 3:22 AM Eastern Time (below). Note that the smoke did not exhibit a signature in the corresponding VIIRS Infrared Window (11.45 µm) image, since thin smoke layers are effectively transparent to infrared radiation.

Suomi NPP VIIRS Day/Night Band (0.7 µm) and Infrared Window (11.45 µm) images at 0722 UTC [click to enlarge]

Suomi NPP VIIRS Day/Night Band (0.7 µm) and Infrared Window (11.45 µm) images at 0722 UTC [click to enlarge]

Daily composites of Suomi NPP VIIRS True Color RGB images with VIIRS Fire Detections viewed using RealEarth (below) showed that thick smoke from wildfires in northern Alberta — primarily the Chuckegg Creek Fire that forced evacuations in the town of High Level — was initially lofted above the meteorological clouds over the Northwest Territories and Nunavut on 19 May and 20 May, before eventually moving southeastward across central/eastern Canada.

Daily composites of Suomi NPP VIIRS True Color RGB images with Fire Detections, 18-22 May [click to play animation]

Daily composites of Suomi NPP VIIRS True Color RGB images with Fire Detections, 18-22 May [click to play animation]

HYSPLIT model 72-hour back trajectories from 3 points corresponding to the smoke filaments seen in the GOES-16 imagery off the Northeast US coast (below) confirmed an initial anticyclonic transport from the region of the Alberta wildfires, with a subsequent southeastward transport across Canada and eventually the Northeast US.

HYSPLIT model 72-hour back trajectories from 3 points off the Northeast US coast [click to enlarge]

HYSPLIT model 72-hour back trajectories from 3 points off the Northeast US coast

6-hourly GFS 500 hPa analyses (source) shown below help to explain the smoke transport as seen in both the VIIRS imagery and the HYSPLIT trajectories — a ridge of high pressure was present over western Canada early in the period, with a transition to a deepening longwave trough over eastern Canada with a shortwave trough digging across Quebec and the Maritimes on 21-22 May. Strong descent of the trajectories occurred during the final 12 hours of transport, on the back side of the digging shortwave trough.

6-hourly GFS 500 hPa analyses [click to enlarge]

6-hourly GFS 500 hPa analyses, from 12 UTC on 18 May to 12 UTC on 22 May [click to enlarge]

Severe thunderstorms in Texas and Oklahoma

May 20th, 2019 |

GOES-16

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

1-minute Mesoscale Domain Sector GOES-16 (GOES-East) “Red” Visible (0.64 µm) images (above) showed the development of widespread thunderstorms that produced tornadoes, large hail (up to 5.5 inches in diameter in Texas) and damaging winds (as high as 94 mph in Oklahoma) (SPC storm reports) across parts of Texas and Oklahoma on 20 May 2019.

The corresponding GOES-16 “Clean” Infrared Window (10.35 µm) images (below) indicated that cloud-top infrared brightness temperatures were frequently as cold as -70 to -80ºC (black to white to violet enhancement) with the more vigorous thunderstorms.

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

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

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

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

Zoomed-in versions of the Visible images (above) and Infrared images (below) are centered at Childress, Texas — which provide a better view of the storms which produced the 5.5-inch hail (Visible | Infrared) at Wellington, Texas and the large tornado near Magnum, Oklahoma (Visible | Infrared | YouTube video).

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

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

One interesting aspect of this line of deep convection: it was effectively acting as an obstacle to the upstream southwesterly flow, resulting in the formation of a quasi-stationary band of gravity waves along its western edge — these waves were very evident in GOES-16 Low-level (7.3 µm), Mid-level (6.9 µm) and Upper-level (6.2 µm) Water Vapor images (below).

GOES-16 Low-level (7.3 µm), Mid-level (6.9 µm) and Upper-level (6.2 µm) Water Vapor images [click to play MP4 animation]

GOES-16 Low-level (7.3 µm), Mid-level (6.9 µm) and Upper-level (6.2 µm) Water Vapor images [click to play MP4 animation]

GOES-16 Split Window Difference (10.3-12.3 µm) images (below) displayed the yellow signature of blowing dust in the vicinity of a cold front that was moving eastward across southeastern New Mexico and southwestern Texas. Blowing dust restricted surface visibility to 3 miles or less at El Paso in Texas and at Alamagordo and Artesia in New Mexico.

GOES-16 Split Window Difference (10.3-12.3 µm) images [click to play animation | MP4]

GOES-16 Split Window Difference (10.3-12.3 µm) images [click to play animation | MP4]

During the subsequent overnight hours, these thunderstorms produced heavy rainfall from northern Oklahoma into southern Kansas, causing flash flooding — and flooding from rising rivers across that region on the following day were captured by the Suomi NPP VIIRS Flood Detection Product (below).

Suomi NPP VIIRS True Color and False Color RGB images, along with the Flood Detection Product [click to enlarge]

Suomi NPP VIIRS True Color and False Color RGB images, along with the Flood Detection Product [click to enlarge]

The river flooding in northern/northwestern Oklahoma was also evident in a before/after comparison of Terra MODIS False Color RGB images from 15 May and 21 May (below). Water appears as darker shades of blue in the False Color images.

Terra MODIS False Color RGB images over northern Oklahoma on 15 May and 21 May [click to enlarge]

Terra MODIS False Color RGB images over northern Oklahoma on 15 May and 21 May [click to enlarge]

Mesoscale Convective System in the Midwest

May 16th, 2019 |

GOES-16

GOES-16 “Red” Visible (0.64 µm) images, 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) displayed a Mesoscale Convective System (MCS) that moved southeast across the Midwestern US on 16 May 2019 (surface analyses), producing a variety of severe weather (SPC storm reports). New convection continued to develop along the MCS outflow boundary, whose western edge was marked by parallel cloud bands from eastern Iowa into northwestern Illinois.

The corresponding GOES-16 “Clean” Infrared Window (10.35 µm) images (below) revealed cloud-top infrared brightness temperatures as cold as -72ºC with some of the overshooting tops.

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]

VIIRS Visible and Infrared images from Suomi NPP (at 1808 UTC) and NOAA-20 (at 1858 UTC) (below) revealed packets of concentric storm-top gravity waves, along with overshooting tops exhibiting infrared brightness temperatures as cold as -78ºC.

VIIRS Visible and Infrared images from Suomi NPP (at 1808 UTC) and NOAA-20 (at 1858 UTC) [click to enlarge]

VIIRS Visible (0.64 µm) and Infrared Window (11.45 µm) images from Suomi NPP (at 1808 UTC) and NOAA-20 (at 1858 UTC) [click to enlarge]

As the MCS approached Madison, Wisconsin it produced a well-defined shelf cloud: