GOES-14 SRSO-R: occluded low pressure in the Upper Midwest

April 21st, 2016

GOES-14 Visible (0.63 um) images, with plots of surface weather symbols in cyan and hail reports in yellow  [click to play MP4 animation]

GOES-14 Visible (0.63 um) images, with plots of surface weather symbols in cyan and hail reports in yellow [click to play MP4 animation]

The GOES-14 satellite was in SRSO-R mode on 21 April 2016, providing 1-minute Visible (0.63 um) images (above; also available as a large 253 Mbyte animated GIF) of the clouds associated with an occluded surface low (surface analyses) in the Upper Midwest. Near the end of the day, thunderstorms in Illinois produced hail of 1.00 and 1.25 inches in diameter (SPC storm reports | HWT Blog post 1 | HWT Blog post 2).

GOES-14 SRSO-R: convective outflow boundary in southern Texas

April 20th, 2016

GOES-14 Visible (0.63 µm) images [click to play MP4 animation]

GOES-14 Visible (0.63 µm) images [click to play MP4 animation]

1-minute interval SRSO-R GOES-14 Visible (0.63 µm) images (above; also available as a large 259 Mbyte animated GIF) showed a curved outflow boundary — produced by a strong quasi-linear convective system the preceding overnight hours in northern Texas — which continued to propagate southward across southern Texas during the day on 20 April 2016. New clusters of convection formed along and in the wake of the eastern portion of the outflow boundary (which dropped an additional 0.67 inch of rainfall in one hour across the flood-ravaged Houston area), while the western portion was marked by a low-level arc cloud.

On the corresponding GOES-14 Water Vapor (6.5 µm) images (below; also available as a large 126 Mbyte animated GIF), a very subtle signature of the western  part of the outflow boundary could be seen in the dryer atmosphere (where the water vapor weighting functions were shifted to lower altitudes). Also of interest were a few long and narrow contrails which appeared within that same dry region of the atmosphere after about 1800 UTC — these thin contrails were not evident in the GOES-14 visible or infrared imagery.

GOES-14 Water Vapor (6.5 µm) images [click to play MP4 animation]

GOES-14 Water Vapor (6.5 µm) images [click to play MP4 animation]

A comparison of the 3 Water Vapor bands (6.5 µm, 7.0 µm and 7.4 µm) available from the GOES-14 sounder instrument (below) demonstrated how each of the individual bands was detecting radiation emitted from a different layer of the troposphere; this was further shown by examining plots of the water vapor weighting functions for the 1 imager and the 3 sounder water vapor bands (calculated using 12 UTC rawinsonde data from Del Rio, Texas KDRT). The ABI instrument on GOES-R will have 3 water vapor bands similar to those on the current generation sounder instrument, but with significantly improved spatial and temporal resolution.

GOES-14 sounder Water Vapor bands 6.5 µm (top), 7.0 µm (middle) and 7.4 µm (bottom) images [click to play animation]

GOES-14 sounder Water Vapor bands 6.5 µm (top), 7.0 µm (middle) and 7.4 µm (bottom) images [click to play animation]

GOES-14 is in Super Rapid Scan Mode

April 18th, 2016

GOES-14 0.62 µm Visible Imagery, 18 April 2016 [click to play animation]

GOES-14 0.62 µm Visible Imagery, 18 April 2016 [click to play animation]

GOES-14 has entered super  rapid scan operations that will continue through 15 May 2016 (Link), in part to support the Hazardous Weather Testbed (HWT) at the Storm Prediction Center (GOES-R HWT Blog) and the VORTEX Southeast experiment. GOES-14 is viewing the central Plains today and tomorrow in anticipation of thunderstorm development. (SPC Day 1 Convective Outlook for 18 April; Day 2 Convective Outlook for 19 April). The visible animation above shows a strong thunderstorm early in the morning on 18 April 2016 near Kerrville TX.

Note that the Twitter Feed @SRSORbot is now active. The bot tweets out 1-hour animations (with 5-minute time steps) every 20 minutes using the latest GOES-14 SRSO-R visible (day) or infrared (night) imagery.

A longer version of the GOES-14 Visible image animation (with overlays of surface weather symbols) is shown below (also available as a large 203 Mbyte animated GIF).

GOES-14 Visible (0.63 µm) images, with plots of surface weather symbols [click to play MP4 animation]

GOES-14 Visible (0.63 µm) images, with plots of surface weather symbols [click to play MP4 animation]

A comparison of GOES-15, GOES-14 and GOES-13 Shortwave Infrared (3.9 µm) images, below, demonstrates the advantage of 1-minute super rapid scan over the routine 15-minute routine scan interval for characterizing the intensity and trends of a short-lived grassfire in far western Oklahoma. Even though a fire hot spot (yellow color enhancement) appeared on the “2000 UTC” GOES-15 and GOES-13 images, the actual scan time of the fire for those 2 satellites was 2004 and 2003 UTC, respectively; a fire hot spot of 317.2 K was first detected on the 2101 UTC GOES-14 image. The magnitude of the fire hot spot then quickly increased to 332.8 K (red color enhancement) on the 2005 UTC GOES-14 image; the short-term fluctuations in the intensity of the fire hot spot were only adequately captured by the 1-minute super rapid scan interval of the GOES-14 images.

GOES-15 (left), GOES-14 (center) and GOES-13 (right Shortwave Infrared (3.9 µm) images [click to play animation]

GOES-15 (left), GOES-14 (center) and GOES-13 (right Shortwave Infrared (3.9 µm) images [click to play animation]

Large storm system over the western/central US

April 17th, 2016

GOES-14 Water Vapor (6.5 µm) images [click to play MP4 animation]

GOES-14 Water Vapor (6.5 µm) images [click to play MP4 animation]

GOES-14 Water Vapor (6.5 µm) images (above; also available as a large 85 Mbyte animated GIF) showed the development of a large upper-level closed low centered over the western US during the 15 April17 April 2016 period. This large storm system was responsible for a wide variety of weather, ranging from heavy snow and high winds in the Rocky Mountains to heavy rainfall and severe weather from eastern Colorado to Texas (SPC storm reports: 15 April | 16 April | 17 April).