The GOES-16 Visible (0.64 µm) image above shows a weak thunderstorm over southeastern Oklahoma surrounding an decaying outflow boundary.  (Click here to see an animation of the visible imagery). The convection did not look particularly robust, but it did produce lightning that was detected by the Geostationary Lightning Mapper (GLM), as shown below.

Lightning requires charge separation in a cloud; typically lightning occurs after the cloud top glaciates. During daytime, glaciation can be detected with ABI Band 5, at 1.61 µm, the so-called Snow/Ice band. The toggle below shows the visible, snow/ice band, and the Baseline Cloud Phase product. Glaciation is indicated.

This case is interesting because NOAA-20 overflew the convection, and soundings were produced around the convection, as shown below.

The animation below steps north-south through seven profiles that surround the weak convection. Note that a profile near the convection has thermodynamic parameters more favorable for convection than at the other profiles.  For example, NUCAPS profiles show the convection at the northern edge of a precipitable water gradient, and also in a local minimum of inhibition.    Although the convection has initiated here, the fields do suggest that NUCAPS can be used to monitor thermodynamics at small scales before initiation.

Horizontal gridded information derived from NUCAPS data will be in AWIPS shortly.  See this post from Emily Berndt at SPoRT!

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The above animation shows the ABI 3.9 µm band for regions of less solar illumination and the ABI 1.6 µm “snow/ice” band for regions more fully illuminated. Also shown is a readout of the GOES-16 cloud-type phase product for a point in eastern Texas. Note how the estimates range for this location from clear sky, liquid water, mixed phase and super-cooled droplets. This shows one example of how to use imagery in conjunction with derived products. These images where generated in AWIPS using a procedure.

Cloud-top phase can be found in RealEarth (search on ‘phase’), GEOCAT (direct link to cloud-top type), and the GOES-R cloud page. An archive of netCDF are held in NOAA’s CLASS.

There are many “Level 2” or derived products generated from the ABI radiances. These include, but are not limited to: cloud proprieties, atmospheric motion, fire, stability, sea and land surface temperatures. More information on these products can be found on the Algorithm Working Group web page, product quality web page or these links.

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Total Precipitable Water (TPW) calculated from rawinsonde data at both Anchorage and Fairbanks, Alaska were all-time record maximum values at 00 UTC on 14 August 2019.

The 0 UTC upper air sounding for Anchorage had a precipitable water value of 1.76″. This easily exceeds the previous all-time record of 1.67″ Aug 26, 1990. @AlaskaWx

— Brian Brettschneider (@Climatologist49) August 14, 2019

The 0 UTC upper air sounding for Fairbanks had a precipitable water value of 1.59″. This exceeds the previous all-time record of 1.57″ July 13, 1971. @AlaskaWx

— Brian Brettschneider (@Climatologist49) August 14, 2019

The microwave-based MIMIC TPW product (below) showed an atmospheric river of moisture moving northeastward toward Alaska during the 2 days leading up to the record-setting TPW values on the Anchorage and Fairbanks soundings. The global view suggested that some of this moisture may have originated from the northern periphery of the TPW reservoir associated with slow-moving Typhoon Krosa in the West Pacific Ocean, being transported eastward then northeastward by a series of frontal waves (surface analyses).

 

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1-minute Mesoscale Domain Sector GOES-16 (GOES-East) “Red” Visible (0.64 µm) and “Clean” Infrared Window (10.35 µm) images (above) displayed the increasing coverage of thunderstorms along the Colorado/Kansas border on 13 August 2019, These thunderstorms produced a few tornadoes and large hail — including hail of 5.00 inches in diameter at 2135 UTC near Bethune in extreme eastern Colorado (SPC storm reports).

 

@NWSBoulder @NWSGoodland I am verifying what looks to be a record setting hailstone for #cowx Am told this fell near Bethune this afternoon. Would easily beat the 4.5″ record… Given the way the radar looked, I wouldn’t be surprised. Stay tuned! pic.twitter.com/LiUazILn6r

— Brian Bledsoe (@BrianBledsoe) August 13, 2019

A toggle between NOAA-20 VIIRS Visible (0.64 µm) and Infrared Window (11.45 µm) images (below) showed the storms at 2022 UTC — just over an hour before the 5.00-inch hail report at 2135 UTC. Note that the NOAA-20 images are incorrectly labelled as Suomi NPP.

The NOAA-20 NUCAPS profile for the green dot in far western Kansas (below) showed that the airmass in advance of the approaching thunderstorms was very unstable, with a Most Unstable parcel Convective Available Potential Energy (MU CAPE) value of 2737 J/kg and a Lifted Index (LI) value of -10ºC (with no Convective Inhibition CINH).

In contrast, the NUCAPS profile for the green dot in eastern Colorado (below) revealed an airmass that was less unstable in the wake of the departing thunderstorms.

===== 14 August Update =====

NWS Goodland Public Information Statement.

 

Preliminary results from NWS Goodland and @ColoradoClimate survey. These results will undergo final review for an official measurement. pic.twitter.com/2E279DeTsa

— NWS Goodland (@NWSGoodland) August 14, 2019

Update: along with @NWSGoodland, today we measured the hailstone that fell NW of Bethune, CO on Tuesday, 13 August. The maximum diameter was 4.83″, which exceeds the long-standing state record of 4.5″. (1/2) #cowx

— ColoClimateCenter (@ColoradoClimate) August 14, 2019

 

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