The MODIS “fog” or 11-3.9 channel difference product for 2012, April 20 at 0431Z shows northern New Mexico dotted with yellow pixels indicating low clouds and/or fog. The MODIS Night-time Microphysics RGB at this time narrows the area of concern. The colors of light to dull aqua (nearly gray & violet) show a small area near and north of Las Vegas NM where fog or low clouds are likely occurring. Surrounding this area in the RGB imagery, the cloud features are more yellow, tan, and orange, indicating a mixture of mid-level clouds (colder, thicker) that are likely further above the surface. The observation at Las Vega (KLVS) shows 10 miles visibility but a ceiling at 600 feet. Luckily this observation verifies what we see in the imagery, but what if the observation was not there? The imagery can help fill the gap between observations as low clouds and fog can be very mesoscale.

