GOES-16 (GOES-East) Split Cloud Top Phase (11.2-8.4 µm) and Dust Red-Green-Blue (RGB) images (above) displayed signatures of blowing dust plumes — medium shades of blue in the 11.2-8.4 µm product, and brighter shades of magenta to pink in the Dust RGB — caused by strong winds in the wake of cold fronts moving southward and eastward  across the central and southern Plains on 09 June 2020.

A closer view of GOES-16 Dust RGB images over the Texas Panhandle (below) showed a localized pocket of dense blowing dust moving southeastward — it temporarily reduced visibility to 2 miles at Borger KBGD, moved across Interstate 40 east of Amarillo KAMA, and then reduced visibility to 3 miles at Childress KCDS.

On a larger scale, a longer animation of GOES-16 Dust RGB images created using Geo2Grid (below) showed the early stages of the initial southward surge of blowing dust over eastern Colorado, where wind gusts to 102 mph were recorded.

The corresponding daytime GOES-16 True Color RGB mages (below) showed the tan-colored plumes of blowing dust, in addition to a few smoke plumes (shades of white) from wildfires in Arizona, New Mexico and the Texas Panhandle.

View only this post Read Less

 

 

GOES-16 (left) and GOES-17 (right) Band 2 (0.64 µm) Visible imagery, 2140 UTC on 8 June 2020 through 0130 UTC 9 June 2020

 

Strong convection developed over Nebraska late in the afternoon of June 8th (SPC Storm reports are here).  Mesoscale domains from both GOES-16 and GOES-17 viewed this developing convection, enabling fine spatial and temporal-scale viewing of the convection.  (Past Mesoscale domain sectors can be searched at this website; this website shows locations in the past year.)

 

The stereoscopic mp4 animation (created using geo2grid and ffmpeg;  a similar blog post on this technique is here) above captures the convective development near 2200 UTC on the 8th, and follows the storm evolution through sunset.  To view the imagery in three dimensions, cross your eyes until three images are present, and focus on the image in the middle.

A 2-panel comparison of GOES-17 and GOES-16 Visible images during the period 2230-0208 UTC is shown below, with time-matched plots of SPC Storm Reports. The images are displayed in the native projection of each satellite.

---

Two other animations (mp4s with imagery every minute from the mesoscale sector), courtesy of Tim Schmit, NOAA/STAR, show the evolution over Nebraska on this day. This one shows the GOES-17 visible imagery from sun-rise through late afternoon; stable wave clouds are evolve into the strong convection noted above. A second animation shows the evolution of the Convection RGB from 2100 UTC on 8 June through 0159 UTC on 9 June. This event is also featured in the CIRA Image of the day (link).

View only this post Read Less

1-minute Mesoscale Domain Sector GOES-16 “Red” Visible (0.64 µm) images (above) revealed low-level vortices that were pivoting around the analyzed center of Tropical Storm Cristobal as it approached the coast of Louisiana on 07 June 2020, making landfall at 2200 UTC. Wind gusts were as high as 57 mph in Louisiana and 64 mph in Mississippi.

GOES-16 Visible images with overlays of GLM Flash Extent Density (below) indicated that there was very little satellite-detected lightning associated with Cristobal.

GOES-16 “Clean” Infrared Window (10.35 µm) images (below) showed numerous cloud-top infrared brightness temperatures as cold as -70 to -77ºC (darker shades of red) within some of the convective bands.

GOES-16 Longwave Infrared Window (11.2 µm) images with plots of Derived Motion Winds (below) showed the broad low-, mid- and upper-level circulation of the tropical storm.

Rich tropical moisture was being transported northward across the Gulf of Mexico by Cristobal — the Blended Total Precipitable Water (TPW) and Percent of Normal TPW product (below) portrayed a large area with TPW values in the 2.5-3.0 inch range, which represented departures of 175-200% of normal. This led to areas of flash flooding along parts of the Gulf Coast, with some locations receiving 4-8 inches of rainfall.

The MIMIC TPW product during the period 03-07 June (below) provided a larger-scale view of the origins of the tropical moisture associated with Cristobal.

View only this post Read Less

GOES-16 ABI Band 13 (10.3 µm) infrared imagery, 1901 6 June 2020 – 0656 7 June 2020 (Click to play mp4 animation)

 

Portions of the High Plains and intermountain states experienced a climatologically rare Derecho event oni 6-7 June 2020. (Here is a preliminary write-up on this event from the National Weather Service in Rapid City SD;  the forecast office in Boulder discussed the event here.). The GOES-16 Clean window infrared (10.3 µm) animation, above, (Click here for the same animation as an animated gif) shows rapid development over western South Dakota late in the afternoon of 6 June. The swath of wind reports is shown in this graphic from the Storm Prediction Center.

Several satellite-based thermodynamic estimates keyed in on South Dakota as a region where instability was noteworthy. The GOES-16 All-Sky Convective Available Potential Energy (available here), shown below from 2026 UTC on 6 June when values were greatest, for example, showed a persistent corridor of instability across South Dakota.

NUCAPS estimates of 700-500 mb lapse rates, below (from this site), show pronounced instability upstream of South Dakota at 1945 UTC, when Suomi-NPP overflew the region. (Most of the soundings used to produce the lapse rate information were from successful infrared retrievals as shown in this graphic).

Surface moisture had pooled over western South Dakota. That is shown in the plot below of surface dewpoints showing very unusual (for South Dakota) mid-60s dewpoints! Further evidence of the unusual moisture amounts over the high Plains (for early June) is in this sounding from Rapid City at 0000 UTC on 7 June (source); Precipitable Water is at 1.2″! This value is unusual for the location and time of year, as shown here (Source).

GOES-17 Full-Disk imagery (at 10-minute time-steps) captured an oblique view of the developing convection. (The ‘PACUS’ sector with 5-minute imagery terminates in west-central South Dakota so is not used here; A GOES-17 Mesoscale sector was not in place for this event, although a GOES-16 one was).

1-minute Mesoscale Domain Sector GOES-16 “Red” Visible images with time-matched plots of SPC Storm Reports are shown below.

View only this post Read Less