GOES-17 IFR Probability Fields are now available via LDM Feed

March 3rd, 2020 |

GOES-17 IFR Probability Fields and Night Fog Brightness Temperature Difference (10.3 µm – 3.9 µm) fields, 1311 UTC on 3 March 2020 (Click to enlarge)

When GOES-15 stopped sending data, IFR Probability fields based on GOES-15 ceased being sent over LDM to users. CIMSS is now sending GOES-17 IFR Probability fields (shown in a toggle above with the Night Fog Brightness Temperature Difference field) via the EXP LDM feed from CIMSS.  Particular strengths of IFR Probability fields include giving a useful low cloud signal below high clouds (as over the western Olympic Peninsula in Washington) and differentiating between elevated stratus and fog, as in the northern Willamette Valley in Oregon.

Note that the Brightness Temperature Difference field shows artifacts related to GOES-17’s poorly-functioning Loop Heat Pipe.  Those artifacts are rapidly diminish day-to-day in early March as GOES-17 enters eclipse season.  Blog posts that discuss GOES-17 IFR Probability are available <a href=”https://fusedfog.ssec.wisc.edu/?cat=36″>here</a>.

GOES-17 IFR Probability Fields in Testing at CIMSS

February 13th, 2020 |

GOES-16 and GOES-17 IFR Probability fields over California, 1641 UTC on 13 February 2020, along with surface observations of ceilings and visibility (Click to enlarge)

GOES-17 IFR Probability fields are being evaluated at CIMSS (the Cooperative Institute for Meteorological Satellite Studies), with a plan to release them to the field via an LDM request in the near future.  The toggle above compares GOES-16 IFR Probability and GOES-17 IFR Probability for the same time over central California. Differences in resolution and parallax shifts are apparent (You can investigate the effect of parallax in a WebApp here).  A similar comparison is shown for Oregon, below, and for Washington, at bottom. GOES-17 IFR Probability fields for CONUS are also available at this website.

GOES-16 and GOES-17 IFR Probability fields over Oregon, 1641 UTC on 13 February 2020, along with surface observations of ceilings and visibility (Click to enlarge)

GOES-16 and GOES-17 IFR Probability fields over Washington, 1641 UTC on 13 February 2020, along with surface observations of ceilings and visibility (Click to enlarge)

Industrial and ship plumes in supercooled clouds

December 4th, 2018 |

MODIS and VIIRS

MODIS and VIIRS “Fog/stratus” BTD images [click to enlarge]

A sequence of nighttime MODIS and VIIRS “Fog/stratus” infrared Brightness Temperature Difference (BTD) images (above) revealed long plumes (darker shades of red) streaming southwestward for over 200 miles from their industrial point sources in the Mesabi Range of northeastern Minnesota on 03 December 2018.

During the subsequent daytime hours, a comparison of GOES-16 (GOES-East) “Red” Visible (0.64 µm), Near-Infrared “Snow/Ice” (1.61 µm), Near-Infrared “Cloud Particle Size” (2.24 µm) and Shortwave Infrared (3.9 µm) images (below) showed signatures of these Mesabi Range plumes along with others emanating from industrial or power plant sources. A few ship tracks were also apparent across Lake Superior.

Particles emitted from the exhaust stacks at power plants and industrial sites (as well as ships) can act as efficient cloud condensation nuclei, which causes the formation of large numbers of supercooled water droplets having a smaller diameter than those found within the adjacent unperturbed supercooled clouds — and these smaller supercooled cloud droplets are better reflectors of incoming solar radiation, thereby appearing brighter in the Near-Infrared and warmer (darker gray) in the Shortwave Infrared images.

GOES-16

GOES-16 “Red” Visible (0.64 µm), Near-Infrared “Snow/Ice” (1.61 µm), Near-Infrared “Cloud Particle Size” (2.24 µm) and Shortwave Infrared (3.9 µm) images [click to play animation | MP4]

On the following night, another sequence of MODIS and VIIRS “Fog/stratus” infrared Brightness Temperature Difference (BTD) images (below) highlighted a number of industrial and power plant plumes across Minnesota, northern Wisconsin and the Upper Peninsula of Michigan. The curved shape of many of these plumes resulted from boundary layer winds shifting from northerly to westerly as the night progressed.

MODIS and VIIRS "Fog/stratus" BTD images [click to enlarge]

MODIS and VIIRS “Fog/stratus” BTD images [click to enlarge]

During the following daytime hours on 04 December, a comparison of VIIRS Visible (0.64 µm), Near-Infrared “Snow/Ice” (1.61 µm), Shortwave Infrared (3.74 µm) and Infrared Window (11.45 µm) images (below) showed 2 plume types across eastern Nebraska. There were several of the brighter/warmer plumes similar to those noted on the previous day across Minnesota/Wisconsin/Michigan — but one large plume originating from industrial sites just east of Norfolk (KOFK) had the effect of eroding the supercooled cloud deck via glaciation (initiated by the emission of particles that acted as efficient ice nuclei) and subsequent snowfall. This is similar to the process that creates aircraft “distrails” or “fall streak clouds” as documented here, here and here.

VIIRS Visible (0.64 µm), Near-Infrared

VIIRS Visible (0.64 µm), Near-Infrared “Snow/Ice” (1.61 µm), Shortwave Infrared (3.74 µm) and Infrared Window (11.45 µm) images [click to enlarge]


Farther to the east over Ohio and Pennsylvania, another example of the 2 plume types was seen (below) — one plume originating from an industrial site near Cleveland was glaciating/eroding the supercooled cloud and producing snowfall, while another bright/warm supercooled droplet plume was moving southeastward from a point source located west of Indiana County Airport KIDI.

The Cleveland plume was captured by an overpass of the Landsat-8 satellite, with a False Color Red-Green-Blue (RGB) image viewed using RealEarth providing great detail with 30-meter resolution (below). A small “overshooting top” can even be seen above the industrial site southeast of Cleveland, with the swath of glaciated and eroding cloud extending downwind (to the southeast) from that point.

Landsat-8 False Color RGB image [click to enlarge]

Landsat-8 False Color RGB image [click to enlarge]

Coincidentally, Landsat-8 also captured another example of a glaciating cloud plume downwind of the Flint Hills Oil Refinery south of St. Paul, Minnesota on 03 December (below). The erosion/glaciation of supercooled cloud extended as far south as Albert Lea, Minnesota. Similar to the Cleveland example, a small “overshooting top” was seen directly over the plume point source.

Landsat-8 False Color RGB image [click to enlarge]

Landsat-8 False Color RGB image [click to enlarge]

===== 08 December Update =====

The effect of this industrial plume glaciating and eroding the supercooled water droplet clouds over northern Indiana was also seen in a comparison of Terra MODIS Visible (0.65 µm), Near-Infrared “Snow/Ice” (1.61 µm) and Infrared Window (11.0 µm) images (below).

Terra MODIS Visible (0.65 µm), Near-Infrared

Terra MODIS Visible (0.65 µm), Near-Infrared “Snow/Ice” (1.61 µm) and Infrared Window (11.0 µm) images [click to enlarge]

===== 09 December Update =====



During the following daytime hours, GOES-16 “Red” Visible (0.64 µm), Near-Infrared “Snow/Ice” (1.61 µm), Near-Infrared “Cloud Particle Size” (2.24 µm), Shortwave Infrared (3.9 µm) and “Clean” Infrared Window (10.3 µm) images (below) showed a number of plumes from industrial sites (many of which were likely refineries) streaming southeastward and eastward over the Gulf of Mexico on 09 December. Note the lack of a plume signature in the 10.3 µm imagery.
GOES-16 "Red" Visible (0.64 µm), Near-Infrared "Snow/Ice" (1.61 µm), Near-Infrared "Cloud Particle Size" (2.24 µm), Shortwave Infrared (3.9 µm) and "Clean" Infrared Window (10.3 µm) images [click to play MP4 animation]

GOES-16 “Red” Visible (0.64 µm), Near-Infrared “Snow/Ice” (1.61 µm), Near-Infrared “Cloud Particle Size” (2.24 µm), Shortwave Infrared (3.9 µm) and “Clean” Infrared Window (10.3 µm) images [click to play MP4 animation]

River valley fog in the Upper Midwest

June 28th, 2018 |

NOAA-20 VIIRS Day/Night Band (0.7 µm) and

NOAA-20 VIIRS Day/Night Band (0.7 µm) and “Fog Product” Infrared Brightness Temperature Difference (11.0 – 3.7 µm) images, with plots of Ceiling and Visibility [click to enlarge]

Suomi NPP VIIRS Day/Night Band (0.7 µm) and "Fog Product" Infrared Brightness Temperature Difference (11.0 - 3.7 µm) images, with plots of Ceiling and Visibility [click to enlarge]

Suomi NPP VIIRS Day/Night Band (0.7 µm) and “Fog Product” Infrared Brightness Temperature Difference (11.0 – 3.7 µm) images, with plots of Ceiling and Visibility [click to enlarge]

Comparisons of NOAA-20 and Suomi NPP VIIRS Day/Night Band (0.7 µm) and “Fog Product” Infrared Brightness Temperature Difference images (above) showed the nighttime formation of river valley fog in parts of the Mississippi River and its tributaries in Minnesota, Wisconsin and Iowa on 28 June 2018.  Due to ample illumination from the Full Moon, the Day/Night Band provided a “visible image at night” with better fog detail in some areas than was seen using the traditional “Fog Product”. (Note: the NOAA-20 images are incorrectly labeled as Suomi NPP)

A toggle between NOAA-20 and Suomi NPP VIIRS Day/Night Band images acquired by the SSEC Direct Broadcast ground station (below) revealed increased fog formation over portions of the Mississippi River between Rochester MN and Madison WI during the 52 minutes separating the two images.

NOAA-20 and Suomi NPP VIIRS Day/Night Band (0.7 µm) images [click to enlarge]

NOAA-20 and Suomi NPP VIIRS Day/Night Band (0.7 µm) images [click to enlarge]

During the subsequent daylight hours, GOES-16 (GOES-East) “Red” Visible (0.64 µm) images (below) showed that the fog dissipated by 15 UTC or 10am local time.

GOES-16

GOES-16 “Red” Visible (0.64 µm) images, with hourly plots of surface weather type [click to play animation | MP4]

GOES-16 Natural Color Red-Green-Blue (RGB) images are shown below.

GOES-16 Natural Color RGB images [click to play MP4 animation]

GOES-16 Natural Color RGB images [click to play MP4 animation]