1 km Visible
This product has the highest resolution of any of the products. It is used for monitoring mesoscale weather features such as cloud cover, air mass boundaries, convergence zones, thunderstorms, and local snow cover. Limited to daytime use.
4 km Visible
Depicts same weather phenomena as the 1 km visible - cloud cover, air mass boundaries, convergence zones, thunderstorms, surface lows, and snow cover, but on a larger scale. Limited to daytime use.
4 km Shortwave IR2
Images at this wavelength consist not only of radiation emitted by the earth atmosphere system, but also reflected solar radiation. Useful for fog and other liquid water cloud identification, cloud phase changes, distinction of cloud cover over snow fields, and fire detection.
4 km Water Vapor IR3
The water vapor channel senses radiation emitted from high clouds and upper level water vapor. This imagery is used to define upper level flow patterns, upper level circulations, and shortwaves moving through the flow.
4 km Thermal Infrared IR4
Used for monitoring cloud top and surface temperature, cloud cover, air mass boundaries, convergence zones, surface lows and thunderstorms both day and night.
4 km Fog/Reflectivity Products
Both of these products are created from the thermal infrared and the shortwave infrared channels. With the fog product, fog and other liquid water clouds can be tracked during the night. The reflectivity product, used during daylight hours, has use in the determination of low clouds over snow fields, the identification of cloud phase, and fire detection. Both channels may be used in conjunction with the longwave infrared channel in the determination of supercooled liquid water clouds.
16 km Water Vapor IR3
The water vapor channel senses radiation from upper level clouds and upper level water vapor. Imagery on this large scale is used to define upper level flow patterns, upper level circulations, and shortwaves moving through the flow.
16 km Thermal Infrared IR4
This imagery is useful for monitoring large scale cloud patterns at the surface, middle, and upper levels both day and night.
4 km Effective Radius
This product retrieves the effective radius of all clouds whose 10.7 µm brightness temperature is colder than -40 C. Pixels warmer than -40 C are replaced with the 10.7 µm brightness temperatures (grayscale), while the effective radii are assigned colors.
The retrieval is performed by first computing the 3.9 µm albedo, then using solar geometry and satellite position along with the 3.9 µm albedo to calculate the associated effective radius from a series of lookup tables. These lookup tables were created by using an observational operator to compute expected 3.9 µm albedos for a wide range of cloud ice crystal sizes and solar geometries. Droxtals are assumed as the ice crystal habit, so scattering phase functions associated with droxtals were used in the model to build the lookup tables.
Research has shown that lower values of ice cloud effective radius are generally associated with high-based thunderstorms with relatively strong updrafts, i.e., the types of thunderstorms common over the Rockies and High Plains during the summer. Additionally, optically thick mountain wave clouds tend to be composed of small ice crystals.
4 km 3-Color Vis/SW/IR
This product is a Red-Green-Blue (RGB) combination of three images. The Red color is used to display the Visible Albedo product; the Green color is used to display the Shortwave Albedo product; and the Blue color is used to display the IR window band (10.7 µm). The Visible Albedo is the solar-zenith-angle-corrected visible (0.7 µm) radiance, corrected to appear as if the sun is overhead at all locations. The Shortwave Albedo is the reflected component only of the Shortwave (3.9 µm) radiance, which is also solar-zenith-angle-corrected to appear as if the sun is overhead at all locations. This product shows non-snow-covered land surfaces as either gray/green, low/water clouds as white, and high/ice clouds as magenta. Snow-covered land surfaces are a different shade of magenta. Also, because of the shortwave band, hot spots from fires may appear in the cloud free areas. This product changes at night when the visible and reflected component of the shortwave bands change characteristics, so it is most useful during the day.
Floater
This loop is centered over a weather feature of interest. It can display any of the GOES channels. See the corresponding MORE INFO button at main menu for information on the imagery displayed in this current loop.
4-Panel loop (Vis, Fog/Ref, WV, IR 4)
This 4-panel loop is composed of visible images (upper-left panel), derived fog/reflectivity images (upper-right panel), 6.7 µm water vapor imagery (lower-left panel), and 10.7 µm infrared window imagery (lower-right panel). The images in the loop are the same as displayed individually in the menu but are reduced in size. The 4-panel loop is useful for comparing clouds and ground features in the various channels. For information on the individual channels displayed in this 4-panel product see their corresponding MORE INFO button on main menu.
GOES Sounder Longwave IR Window (band-8, 11 µm)
Used for monitoring cloud top and surface temperature, cloud cover, air mass boundaries, convergence zones, surface lows and thunderstorms both day and night.
GOES Sounder Skin Temperature
The GOES Sounder skin temperature product represents the radiative skin temperature of the earth's land or water surface. This product is generated by correcting the GOES IR window channel for atmospheric absorption effects, those mainly due to water vapor absorption. By using both the IR window channel (channel-8, 11. µm) and the "dirty" window (channel-7, 12. µm), atmospheric absorption can be estimated. The absorption is effectively determined as the temperature difference between the two window channels. This temperature difference is doubled to reflect the amount of atmospheric absorption in the window channel (based on theoretical calculations) and added back into the GOES window channel to determine a temperature without atmospheric effects. The amount of temperature correction is typically small, even when doubled, and is usually only a few degrees Celsius at most. The temperature correction can also be negative. In those cases the surface is colder than the air above the surface, as occurs in temperature inversions. The areas of negative temperature differences are the color-enhanced areas in the longwave IR difference product.
GOES Sounder Longwave IR (channel-8 minus channel-6) Difference
This product is the temperature difference between two longwave IR channels of the GOES Sounder, channel-8 (11 µm) a "clean" window channel and channel-6 (12 µm) a "dirty" window with some atmospheric absorption. The temperature difference between these channels is usually positive, with small negative differences possible. Larger positive differences (dark areas) are usually caused by differential transmission thru semi-transparent ice clouds, such as cirrus; and smaller positive differences (lighter gray areas) are normally observed over land. These smaller differences are the result of differential absorption usually due to low-level moisture, with more moisture causing more difference between the channels (darker as opposed to lighter areas). However moisture is not the only cause of a difference between the channels. Small differences between the channels may also be the result of ground surfaces with low emissivity (less than the assumed emissivity of 1.0) or may be the result of surface temperature inversions. These inversion sometimes cause negative differences between the channels (the whitest areas).
GOES Sounder Day/Night Albedo
The GOES visible albedo product effectively enhances the visible channel images, creating a product that brightens up darker areas of the image due to low sun angle. The solar zenith angle at every image pixel is used to generate an isotropic albedo, independent of sun angle. At night, or for the night portion of images containing the terminator, the shortwave IR albedo product (see this product for an explanation) is substituted in place of darkness. This creates a continuous display of cloud features day and night. Low-level water clouds appear white both day and night. Higher-level ice clouds, such as cirrus, appear dark at night, white during the day.
GOES Sounder Shortwave IR Albedo
This is the same product as the shortwave IR albedo derived using GOES Imager channels 2 and 4, but using Sounder channel-8 (longwave IR, 11 µm) and channel-18 (shortwave IR, 3.7 µm). See the equivalent Imager product for an explanation of how this product is generated. Low-level water clouds appear white both day and night. Higher-level ice clouds, such as cirrus, appear dark at night, white during the day.
GOES Sounder Upper-Level Water Vapor
The central wavelength for this water vapor channel is at 6.5 µm, with a vertical weighting function peak at about 300 hPa, the highest of the three Sounder water vapor channels.
GOES Sounder Middle-Level Water Vapor
The central wavelength for this water vapor channel is at 7.0 µm, with a vertical weighting function peak at about 500 hPa, the middle of the three Sounder water vapor channels.
GOES Sounder Lower-Level Water Vapor
The central wavelength for this water vapor channel is at 7.4 µm, with a vertical weighting function peak at about 700 hPa, the lowest of the three Sounder water vapor channels.
GOES Imager Water Vapor
The water vapor channel senses radiation emitted from high clouds and upper level water vapor. This imagery is used to define upper level flow patterns, upper level circulations, and shortwaves moving through the flow.
GOES Day/Night Albedo
The GOES visible albedo product effectively enhances the visible channel images, creating a product that brightens up darker areas of the image due to low sun angle. The solar zenith angle at every image pixel is used to generate an isotropic albedo, independent of sun angle. At night, or for the night portion of images containing the terminator, the shortwave IR albedo product (see this product for an explanation) is substituted in place of darkness. This creates a continuous display of cloud features day and night. Low-level water clouds appear white both day and night. Higher-level ice clouds, such as cirrus, appear dark at night, white during the day.
GOES Shortwave IR Albedo
The GOES shortwave albedo product is generated by subtracting the equivalent thermal radiance in the shortwave IR channel (3.9 µm) using the longwave IR (10.7 µm) temperature. This is done using the same formula day or night, whether or not there is reflected solar radiation. Since the surface albedo and emissivity are inversely related, areas that reflect solar radiation during the day are actually areas with lower emissivity or a radiance deficit, compared to the longwave IR channel, at night. The solar zenith angle at every image pixel is used to generate an isotropic albedo, independent of sun angle. This new product, which emphasizes low-level water cloud features, may replace the combined nighttime fog / daytime reflectivity product which is generated differently night and day.
GOES Skin Temperature
The GOES skin temperature product represents the radiative skin temperature of the earth's land or water surface. This product is generated by correcting the GOES IR window channel for atmospheric absorption effects, those mainly due to water vapor absorption. By using both the IR window channel (channel-4, 10.7 µm) and the "dirty" window (channel-5, 12.0 µm), atmospheric absorption can be estimated. The absorption is effectively determined as the temperature difference between the two window channels. This temperature difference is doubled to reflect the amount of atmospheric absorption in the window channel (based on theoretical calculations) and added back into the GOES window channel to determine a temperature without atmospheric effects. The amount of temperature correction is typically small, even when doubled, and is usually only a few degrees Celsius at most. The temperature correction can also be negative. In those cases the surface is colder than the air above the surface, as occurs in temperature inversions. The areas of negative temperature differences are the color-enhanced areas in the longwave IR difference product.
GOES Longwave IR (channel-4 minus channel-5) Difference
The longwave IR difference is generated as the change in temperature between the IR window channel (channel-4, 10.7 µm) and the "dirty" window (channel-5, 12.0 µm). This temperature difference is due to changes in atmospheric absorption or transmission between the two channels. The transmission differences are mainly due to clouds that allow different amounts of surface radiation to reach the satellite. The largest positive differences (dark areas) are generally due to differential transmission thru thin cirrus clouds. The absorption differences are mainly due to low-level water vapor when the dirty window has a lower radiative temperature than the "clean" window channel. Smaller positive differences (lighter gray areas) indicate changes in low-level moisture, which are most significant in the summer, with more moisture causing more difference between the channels (darker as opposed to lighter areas). Negative differences (the whitest areas) can occur when the surface is colder than the air above the surface, as in temperature inversion situations.
AMSU Product 1 - Total Precipitable Water
Column integrated water vapor amount. The scale is in half inch (12.5 mm) increments from zero to three inches (75 mm). Gray indicates that no retrieval is possible, for example, where heavy rain is occurring. [Retrieved by the NOAA/NESDIS Microwave Sensing Group.]
AMSU Product 2 - Rain Rate
The instantaneous rainfall rate. Green: 0-10 mm/hr. Red: 10-35 mm/hr. Gray indicates that no retrieval is possible, for example, over sea ice. [Retrieved by the NOAA/NESDIS Microwave Sensing Group.]
AMSU Product 3 - Channel 7 Brightness Temperature
Brightness temperature at 54.9 GHz. Range: 207.7 K to 233.2 K.
AMSU Product 4 - Cloud Liquid Water
Column integrated liquid water amount. Navy: zero. Light blue through magenta: >0 to 6 mm. [Retrieved by the NOAA/NESDIS Microwave Sensing Group.]
AMSU Product 5 - Sea Ice
Fractional coverage of sea ice. Navy to white: 0-100%. [Retrieved by the NOAA/NESDIS Microwave Sensing Group.]
AMSU Product 6 - Snow Cover
Snow cover. Currently only three values are allowed. Tan: no snow. Red: 50% cover/"old" snow. White: 100%/"new" snow. [Retrieved by the NOAA/NESDIS Microwave Sensing Group.]
AMSU Product 7 - 89 GHz
Brightness temperature at 89 GHz. Black to white: 198 K (or less) to 325 K. The clear ocean is dark because its low emissivity causes it to have a low brightness temperature. Water vapor and cloud liquid water brighten the image. Land has a high emissivity and thus appears bright. Scattering by ice particles in clouds (or snow) causes very low brightness temperatures (dark spots).
AMSU Product 8 - 150 GHz
Brightness temperature at 150 GHz. Black to white: 198 K (or less) to 325 K. 150 GHz images are similar to 89 GHz images except that (1) they are generally brighter because the atmosphere is less transparent at 150 than at 89 GHz, (2) 150 GHz is more sensitive to scattering than is 89 GHz, and (3) along-track anomalies in the image are the result of radio frequency interference from the HRPT antennas.
Suomi NPP VIIRS Products
VIIRS granules in McIDAS-X (M-band example). Example is SDR with bow-tie deletions at ends of granule filled in.
Full granule (768 x 3200)
Center half (768 x 1600)
Suomi NPP VIIRS Products Remapped to Mollweide Projection
Full granule remapped to Mollweide projection