Thunderstorms developing in the warm sector of a low pressure system (surface analyses) produced tornadoes, large hail and damaging winds (SPC storm reports) across parts of the Deep South late in the day and into the night on 19 March 2018. GOES-16 (GOES-East) “Red” Visible (0.64 µm) images at 30-second intervals (above) showed numerous overshooting tops associated with this cluster of supercell convection.

In the corresponding GOES-16 “Clean” Infrared Window (10.3 µm) images (below), cloud-top infrared brightness temperatures of some overshooting tops were around -70 ºC  (black enhancement).

Note that the EF-3 tornado that damaged the Jacksonville State University area in Alabama around 0135 UTC was the first EF-3 in 306 days — a new record.

UPDATE/CORRECTED: the damage survey continues, and based on an assessment of structures in the vicinity of Jacksonville State University the tornado intensity has been UPGRADED to an EF-3 with winds around 140mph.

— NWS Birmingham (@NWSBirmingham) March 20, 2018

After 306 consecutive days without an F3/EF3+ tornado in the United States, the remarkable drought has come to an end. This is the longest such streak since NOAA records began in the 1950s. pic.twitter.com/gPPqGWRTYP

— Steve Bowen (@SteveBowenWx) March 20, 2018

Additional animations are available on the Satellite Liaison Blog.

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One of the Level-2 products in AWIPS is Sea-Surface Temperature.  This is created hourly on the Full Disk scale, and is shown above.   The image above toggles between the default enhancement (from -5º to 40º Celsius) to one that is more appropriate for mid-March (-5º to 30º Celsius), and then with the ABI Band 2 (0.64 µm) Visible Image.  This allow change allows for features in the Gulf of Mexico to become more obvious. (Note: The default Sea-Surface Temperature enhancement in AWIPS will change in the future; the maximum value will be 35º C, not 40º).

Sea-Surface temperatures over the Great Lakes, under clear skies, are not displayed. Sea-Surface temperatures are currently computed only over the oceans — not over large lakes.

GOES-16 Land Surface Temperature, computed hourly in the CONUS domain, does include Great Lakes water temperatures; it is shown below (Here is it in a toggle with different ABI Channels). The default temperature scale for Land Surface Temperature is -10º to 110º (Fahrenheit), which is different than the default for Sea-Surface Temperatures. The cold mid-March temperatures (low to mid-30s, generally, with a few sub-30s showing over ice) of the Great Lakes stand out plainly. Regions of ice do persist over the Great Lakes, as is apparent in this toggle between ABI’s Visible (Band 2, 0.64 µm), Snow/Ice Near-Infrared (Band 5, 1.61 µm) and Cirrus Near-Infrared (Band 4, 1.37 µm) Imagery at 1502 UTC.    Lake ice remains over eastern Lake Erie, eastern and northern Lake Superior, and north of Manitoulin Island in Lake Huron.

(Note: Plans exist to include large lake surface temperatures in the computation of Sea-Surface temperature at some point in the future.)

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Thunderstorms developing east of an advancing dryline (surface analyses) produced large hail (SPC storm reports) across south-central and eastern Texas late in the day on 18 March 2018. GOES-16 (GOES-East) “Red” Visible (0.64 µm) images (above) showed well-defined overshooting tops and above-anvil cirrus plumes associated with this severe convection.

In the corresponding GOES-16 “Clean” Infrared Window (10.3 µm) images (below), cloud-top infrared brightness temperatures of some overshooting tops fluctuated within the -70 to -80 ºC range (black to white enhancement).

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As documented by NWS Milwaukee/Sullivan, the controlled burn of an apartment building occurred during the late morning hours on 15 March 2018. A comparison of GOES-16 (GOES-East) Shortwave Infrared (3.9 µm) and “Red” Visible (0.64 µm) images (above) displayed subtle “hot spot” signatures (darker red pixels, circled) as well as an occasional hint of a small smoke plume during the early phase of the fire. At the bottom of the images, note the appearance of a few larger and hotter fires (black pixels) in northern Illinois — likely agricultural fires to prepare fields for Spring planting.

2 days later, another structure fire occurred in the San Francisco area during the early evening hours of 17 March 2018:

A four-alarm fire in San Francisco’s North Beach neighborhood picked up on GOES-E this evening from 7:42 PM to 8:02 PM PDT. GOES-E “Nighttime Microphysics RGB” channel is typically used for fog detection. #SanFrancisco #NorthBeach #NorthBeachFire #GOES16 @NOAASatellites pic.twitter.com/dx9wSwp6QM

— NWS Bay Area (@NWSBayArea) March 18, 2018

Hot spot signatures were observed on the 0247 UTC and 0252 UTC (7:47 and 7:52 PM local time) Shortwave Infrared (3.9 µm) images, along with subtle lighter gray pixels on the Near-Infrared (2.24 µm) images (below).

A timely overpass of the NOAA-15 satellite scanned the fire at 02:43:50 UTC (7:43:50 PM local time), showing a well-defined hot spot (darker red enhancement) on the 1-km resolution Shortwave Infrared (3.7 µm) image (below).

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