GOES-14 SRSOR: Thunderstorm development over Kentucky

May 22nd, 2014
GOES-13 DPI Convective Available Potential Energy (CAPE) on May 22, times as indicated (click to play animation)

GOES-13 DPI Convective Available Potential Energy (CAPE) on May 22, times as indicated (click to play animation)

GOES-14 operations in SRSOR mode deliver the ability to monitor convective development at very short time-scales. A good example of this occurred over the lower Ohio Valley/western Kentucky on May 22nd. The animation of GOES-13 Sounder Derived Product Imagery of CAPE (above) and of Lifted Index (1300 and 1700 UTC) showed considerable instability waiting to be released.

GOES-14 SRSOR animations can be used to monitor the evolving cumulus field in the search for the tower that will break the cap (Nashville, TN/Lincoln IL Soundings from 1200 UTC). The animation below shows visible imagery from 1800 UTC through 2011 UTC, at which time the convection has developed. Initial convection dissipates, but eventually develops along the Ohio River in western Kentucky (cumulus clouds continue to grow/dissipate over the Mississippi River valley throughout the animation).

GOES-14 Visible Imagery (0.62 µm) on May 22, times as indicated (click to play animation)

GOES-14 Visible Imagery (0.62 µm) on May 22, times as indicated (click to play animation)

By 1900 UTC, convective development over the lower Ohio Valley is vigorous enough that Cloud-Top Cooling algorithm from CIMSS (below) has flagged growing clouds, with values exceeding 20º C/15 minutes.

Instanteous Cloud-Top Cooling computed from GOES-13 at 1900 UTC 22 May 2014 (click to enlarge)

Instanteous Cloud-Top Cooling computed from GOES-13 at 1900 UTC 22 May 2014 (click to enlarge)

How does the NOAA/CIMSS ProbSevere model  then change with time as the convection intensifies? The 1904 and 1906 UTC ProbSevere products, toggled below, shows values increasing from 49% to 54% as Satellite Growth rates at 1900 UTC are incorporated at 1906 UTC. ProbSevere values then dropped (1912 UTC, 1922 UTC) as MRMS MESH decreased.

NOAA/CIMSS ProbSevere from 1904 and 1906 UTC on 22 May 2014 (click to enlarge)

NOAA/CIMSS ProbSevere from 1904 and 1906 UTC on 22 May 2014 (click to enlarge)

By 1936 UTC, ProbSevere has again increased above 50%, in two regions where MRMS has MESH sizes over 0.50″. MESH values are equivalent in the two regions, as are environmental values, but higher satellite predictors associated with the smaller eastern radar object drive higher ProbSevere values there.

NOAA/CIMSS ProbSevere from 1936 UTC on 22 May 2014 (click to enlarge)

NOAA/CIMSS ProbSevere from 1936 UTC on 22 May 2014 (click to enlarge)

The animation below shows the evolution of NOAA/CIMSS ProbSevere from 1948 UTC through 2000 UTC, with focus on a second cell that was warned. NOAA/CIMSS ProbSevere is designed to give an estimate of when severe weather might initially occur. Severe weather was not reported in Kentucky with these storms (link); however, observations of severe weather did occur as the storms moved near Nashville.

NOAA/CIMSS ProbSevere from 1948-2000 UTC on 22 May 2014 (click to animate)

NOAA/CIMSS ProbSevere from 1948-2000 UTC on 22 May 2014 (click to animate)

Related Hazardous Weather Testbed blog posts on this event can be found here, here, and here.

Slide Fire in Arizona

May 22nd, 2014
GOES-13 0.63 µm visible channel images (click to play animation)

GOES-13 0.63 µm visible channel images (click to play animation)

McIDAS images of GOES-13 (GOES-East) 0.63 µm visible channel data (above; click image to play animation) showed the rapid growth of the smoke plume from the Slide Fire which was burning in Arizona on 21 May 2014.

As the fire continued to burn into the night, a comparison of AWIPS images of 375-meter resolution Suomi NPP VIIRS 3.74 µm and 4-km resolution GOES-13 3.9 µm shortwave IR images (below) demonstrated the advantage of improved spatial resolution (and a more direct viewing angle) of the VIIRS data for determining both the intensity and the true location of the fire hot spots around 10 UTC or 4 am local time.

Suomi NPP VIIRS 3.74 µm and GOES-13 3.9 µm shortwave IR image comparison

Suomi NPP VIIRS 3.74 µm and GOES-13 3.9 µm shortwave IR image comparison

On the following morning, GOES-15 (GOES-West) 0.63 µm visible channel images (below; click to play animation) the smoke plume aloft and smoke which had settled into valleys could be seen during the early morning hours.

GOES-15 0.63 µm visible channel images (click to play animation)

GOES-15 0.63 µm visible channel images (click to play animation)

Suomi NPP VIIRS true-color Red/Green/Blue (RGB) images from 21 May and 22 May are visualized using the SSEC RealEarth web map server (below). On 22 May, bands of high-altitude cirrus clouds were moving over the region, making the identification of the north/northwestward-moving smoke plume a bit more difficult.

Suomi NPP VIIRS true-color RGB images (21 and 22 May)

Suomi NPP VIIRS true-color RGB images (21 and 22 May)

Cyclonic transport of fire smoke over the Gulf of Alaska

May 21st, 2014
GOES-15 0.63 µm visible channel images (click to play animation)

GOES-15 0.63 µm visible channel images (click to play animation)

McIDAS images of GOES-15 0.63 µm visible channel data (above; click image to play animation) showed the cyclonic transport of smoke across the Gulf of Alaska on 20 May 2014. The source of the smoke was the Funny River Fire that was burning on the Kenai Peninsula of south-central Alaska, near Soldotna. The fire quickly grew to 20,000 acres in about 24 hours.

The curved smoke plume was also quite evident on 3 separate Suomi NPP VIIRS 0.7 µm Day/Night Band images (below). Smoke was reducing the surface visibility as low as 3 miles at Homer (station identifier PAHO).

Suomi NPP VIIRS 0.7 µm Day/Night Band images

Suomi NPP VIIRS 0.7 µm Day/Night Band images

Even though patchy clouds covered the Kenai Peninsula region around 13 UTC, the fire “hot spots” (black to yellow to red color enhancement) were still detectable on the VIIRS 3.74 µm shortwave IR image (below).

Suomi NPP VIIRS 0.7 µm Day/Night Band and 3.74 µm shortwave IR channel images

Suomi NPP VIIRS 0.7 µm Day/Night Band and 3.74 µm shortwave IR channel images

GOES-14 SRSOR: Storm-centered Loop of Supercell over the High Plains of Colorado

May 21st, 2014
GOES-14 0.62 µm visible channel images (click to play animation)

GOES-14 0.62 µm visible channel images (click to play animation)

An isolated Supercell Thunderstorm developed near Denver on 20 May and then moved eastward over the High Plains. The storm produced significant hail. GOES-14 was operating in SRSOR mode and viewing Colorado during the storm’s lifecycle, and the animation above (click image for a large animated gif file) is centered on the storm, highlighting the inflow into the storm from the southeast and the strong difluence around the updraft.

An earth-centered animation is available here. The animated gif clickable above is also available as a YouTube video, or downloadable in mp4 format here.

This animation shows the visible and the 10.7 µm infrared for the same time period. (Also available on YouTube).

(Two more YouTube Videos: Visible (mp4 here) and Infrared (mp4 here), with some bad lines removed)