GOES-14 SRSO-R: heavy snow in the Upper Midwest, severe thunderstorms in the Deep South

February 2nd, 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]

A strong occluded mid-latitude cyclone moved from the central Plains northeastward across the Upper Midwest on 02 February 2016 (surface analyses). This storm produced a variety of precipitation, most notably heavy snow — exceeding 12 inches at some locations in Nebraska, Iowa, Minnesota, Wisconsin, and the Upper Peninsula of Michigan (map) — and blizzard conditions. One-minute interval Super Rapid Scan (SRSO-R) GOES-14 Visible (0.63 µm) images (above; also available as a large 151-Mbyte animated GIF) showed the cloud-top shadows and textured appearance that is indicative of embedded convection — in fact, many sites in Iowa and southern Wisconsin reported thundersnow which produced snowfall rates of 1-2 inches per hour.

Farther to the south, as moisture from the Gulf of Mexico was drawn northward (GOES-14 sounder Total Precipitable Water derived product images) in advance of the eastward-moving cold frontal boundary (surface analyses) associated with the aforementioned Upper Midwest storm, areas of strong to severe thunderstorms developed across the Mississippi River and Tennessee River Valley regions during the afternoon and evening hours. GOES-14 Infrared Window (10.7 µm) images (below; also available as a large 208-Mbyte animated GIF) showed the cold cloud-top IR brightness temperatures (orange to red color enhancement) exhibited by the widespread convective activity.

GOES-14 Infrared Window (10.7 µm) images [click to play MP4 animation]

GOES-14 Infrared Window (10.7 µm) images [click to play MP4 animation]

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

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

Taking a closer look at the severe thunderstorms which produced multiple tornadoes from eastern Mississippi  into far western Alabama (SPC storm reports), GOES-14 Visible (0.63 µm) images (above; also available as a large 66-Mbyte animated GIF) revealed numerous overshooting tops; the counties where tornadoes were reported are indicated by their dashed red outlines. Another visible image animation from RAMMB/CIRA is available here. NWS storm damage surveys (Jackson MS | Birmingham AL) found EF-1 to EF-2 damage in both Mississippi and Alabama.

The corresponding GOES-14 Infrared Window (10.7 µm) images (below; also available as a large 37-Mbyte animated GIF) indicated that the coldest cloud-top IR brightness temperatures were in the -50º to -60º range (darker orange to red color enhancement), which was at or above the tropopause level according the Jackson MS and Birmingham AL rawinsonde data.

GOES-14 Infrared Window (10.7 µm) images [click to play MP4 animation]

GOES-14 Infrared Window (10.7 µm) images [click to play MP4 animation]

GOES-14 Sounder Operations

January 31st, 2016

GOES-14 Sounder DPI of Total Precipitable Water (TPW) at 1800 UTC on 31 January 2016 [Click to enlarge]

GOES-14 Sounder DPI of Total Precipitable Water (TPW) at 1800 UTC on 31 January 2016 [click to enlarge]

GOES-14, over the Equator at ~105º W Longitude, has been activated in support of SRSO-R Operations in February 2016. One-minute imagery will commence on Monday 1 February. The GOES-14 Sounder has also been activated to fill in, temporarily, for the GOES-13 Sounder that has been inactive since November 2015. An animation of all 19 Sounder channels is available at this link; animations of Derived Product Images (DPI) of Total Precipitable Water from GOES-14, as shown above, are available here, with GOES-14 DPI of Lifted Index available here.

GOES-13 Sounder Anomalies

November 23rd, 2015

GOES-15 Visible (0.63 µm) images [click to play animation]

GOES-13 Sounder Band 5 Infrared (13.4 µm) images, 0847 and 0947 UTC on 20 November [click to enlarge]

On 20 November, at 0922 UTC, the GOES-13 Sounder experienced an anomaly (the GOES-13 Sounder had Filter Wheel anomalies in 2012 as well: Link; Link). GOES Engineers determined that the Filter Wheel had stopped moving (the filter wheel aligns the infrared detectors with the incoming data) so data were not scanned. The image above shows the 13.4 µm (a CO2 channel) image before and after the anomaly. All 18 infrared channels are affected; the visible channel (band 19) continues sending usable data. GOES Engineers continue to investigate the problem. GOES Sounder derived products (such as Total Precipitable Water) are affected, and are no longer being produced or disseminated (Link). From an email from SSD: (Link)

*Update #2: * **Effective immediately; all the GOES-13 (GOES-East)
sounding products are ceased to produce and stop distribution as we are
experiencing an anomaly with the sounder instrument. Engineers are
investigating the problem. We will inform you when we resume our normal
operations.

*Update #1: * GOES-13 (GOES-East) Sounder IR Data Outage

*Topic:* GOES-13 (GOES-East) Sounder IR Data Products Outage

*Date/Time**Issued:*November 20, 2015 1955Z*
*

*Product(s) or Data Impacted:*

GOES-13 (GOES-East) Sounder data
Blended Hydrometorological Products – Blended TPW
Microwave AWIPS Products – Blended TPW
Microwave McIDAS Products – Blended TPW
GOES Gridded Cloud Product
GOES VARiable data
AFEP/Ingestor – GOES
N-AWIPS Ingest
Single Field of View BUFR
Single Field of View SDPI for AWIPS
Single Field of View TPW
Sounding ASOS SCSP
Web Pages

*Date/Time of Initial Impact:*November 20, 2015 0922Z **

*Date/Time of Expected End:* TBD

*Length of Outage:* TBD

*Details/Specifics of Change:*GOES-13 (GOES-East) Sounder instrumentis experiencing an anomaly. Engineers are investigating the problem. GOES-13 Sounder IR data is not available. **Effective immediately all the GOES-13 (GOES-East) sounding products are ceased to produce and stop distribution as we are experiencing an anomaly with the sounder instrument. Engineers are investigating the problem. We will inform you when we will resume our normal operations.


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Update 19 January 2016
==================================================================

GOES-14 is scheduled to broadcast 1-minute SRSO-R data starting 1 February. GOES-14 will be activated on 25 January, with a maneuver shortly thereafter. It is likely that GOES-14 Sounder data will be broadcast from 1-25 February (GOES-14 Sounder Timing will be adjusted to match GOES-13 Sounder Timing) when the GOES-14 Imager is broadcasting SRSO-R data.

Tornado in central California

November 15th, 2015

GOES-15 Visible (0.63 µm) images [click to play animation]

GOES-15 Visible (0.63 µm) images [click to play animation]

An EF-1 tornado was on the ground for about 20 minutes near Denair (Local Storm Report | Facebook post) in central California on 15 November 2015. 1-km resolution GOES-15 Visible (0.63 µm) images (above) showed that clusters of small thunderstorms rapidly developed in an environment of instability along and just behind a fast-moving cold frontal boundary. The location of the tornado is indicated by a red “T” on the 2145, 2200, and 2211 UTC images. Very strong southwesterly winds aloft allowed the upwind portion of the highly-tilted thunderstorms to be brightly illuminated by the low sun angle of late afternoon in mid-November.

The corresponding 4-km resolution GOES-15 Infrared (10.7 µm) images (below) revealed that cloud-top IR brightness temperatures quickly cooled from -23º C at 2130 UTC to -42º C at 2200 UTC.

GOES-15 Infrared (10.7 µm) images [click to play animation]

GOES-15 Infrared (10.7 µm) images [click to play animation]

There was a 30-minute gap in GOES-15 coverage from 2100 to 2130 UTC (due to a full disk scan), but a comparison of 1-km resolution NOAA-19 AVHRR Visible (0.63 µm) and Infrared (10.8 µm) caught the very early growth of the tornado-producing storm at 2115 UTC (below). The cloud-top IR brightness temperatures were as cold as -23º C at that time, indicating a high probability that cloud glaciation had begun.

NOAA-19 Visible (0.63 µm) and Infrared (10.8 µm) images [click to enlarge]

NOAA-19 Visible (0.63 µm) and Infrared (10.8 µm) images [click to enlarge]

A timely overpass of the Suomi NPP satellite allowed a comparison of 375-meter resolution VIIRS Visible (0.64 µm) and Infrared (11.45 µm) images during the time that the tornado was srill on the ground (below). Once again, the strong slant of the storms due to increasing wind speeds aloft allowed the western/southwestern sides of the thunderstorm clouds to be brightly illuminated on the visible image. The coldest cloud-top IR brightness temperature was -51º C (yellow color enhancement), which was just shy of the -53º C tropopause temperature reported on the Oakland rawinsonde report at 12 UTC.

Suomi NPP VIIRS Visible (0.64 µm) and Infrared (11.45 µm) images [click to enlarge]

Suomi NPP VIIRS Visible (0.64 µm) and Infrared (11.45 µm) images [click to enlarge]

A VIIRS true-color image of the storm visualized using RealEarth is shown below. The actual satellite overpass time was around 2151 UTC.

Suomi NPP VIIRS true-color image [click to enlarge]

Suomi NPP VIIRS true-color image [click to enlarge]

GOES-15 sounder Lifted Index (LI) derived product images (below) showed the pockets of post-frontal instability over central California — LI values less than -4 C were seen (yellow color enhancement).

GOES-15 sounder Lifted Index derived product images [click to play animation]

GOES-15 sounder Lifted Index derived product images [click to play animation]