RGB Nighttime Microphysics at ABQ

Early morning low clouds and fog on April 6, 2012 across the eastern plains of NM were detected exceptionally well in the new RGB nighttime microphysics product at ABQ.  The first image shows the fog and low clouds along the TX state line creeping westward into NM.  The fog and low clouds across the east contrast very well with the mid level cloud cover farther to the west over the Sangre de Cristo and San Juan mountains.  The second imagery is the MODIS 11-3.9micron product.  Note the presence of speckled yellow areas over the east central and southeast portions of the state that are not present in the RGB imagery.  This information was useful for composing short-term forecasts.  A graphicast was also created using the combined fog depth product later in the morning as it is available roughly every 20 minutes versus the swath dependent MODIS.

MODIS RGB NT microphysics product 20120406 0835UTC

Hybrid_Fog_SRW_20120406_0832UTC

Short-term graphicast 20120406

4 thoughts on “RGB Nighttime Microphysics at ABQ

  1. Brian, I enjoyed reading your post and seeing the application of the RGB imagery as an improvement over the standard GOES 11-3.9 spectral difference product. I would like to add that the Night-time Microphysics RGB indication of fog in the upper right of the posted image (northeast NM, norwest TX) has variations in the shades of aqua (i.e. fog). Note that the western edge of the aqua has brighter, more solid aqua coloring. Fog is likely more dense here. A bit more to the east, the aqua coloring is a bit darker due to influence of the underlying surface emissions; hence more of the blue color is contributing here as the warm surface temperature emissions come through the fog in this area. Fog here may be a bit more disperse or non-uniform.

  2. Hey Brian…nice post!

    It was also interesting to note the differences between the Nighttime Microphysics RGB vs. the 11-3.9u imagery. In particular, the area of “noisy” appearance in the 11-3.9u imagery (the yellow blotches) is not nearly as readily apparent as in the RGB imagery. The observations likewise seem to indicate that neither fog nor low clouds were present in these areas in central to east-central NM. However, do you happen to know if shallow fog was present in those areas that morning? I have often seen this blotchy appearance in the 11-3.9 imagery here in our forecast area (Huntsville, AL), but it is often not associated with any type of low cloud or fog.

    • Thanks Kris. We were not able to find any indication of fog in those areas with the yellow blotches. Interestingly the yellow areas farther south follow closely with the topographical relief of the Caprock and the Pecos River Valley. I wonder if it is possible that there is some contribution from the surface vegetation or emissivity in those areas that creates this effect…which can also be seen as a more purplish pink in the NT micro physics product. Now I am curious what the GVF depicted for that day.

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