Dust over Mexico and the US

By Jochen Kerkmann (EUMETSAT)

On 23 March, GOES-16, the new American geostationary weather satellite, observed, for the first time, a major dust outbreak over Mexico and south-western America.

The dust was picked up by strong south-westerly winds related to a deep trough over the western US.

On the GOES-16 Dust RGB (Figure 1) the dust can be seen as a pink area as it travelled from northern Mexico to Texas and New Mexico in America.

On the animated gif (Figure 2) the dust sources of this outbreak can be seen (dust hot spots), mostly located in northern Mexico, but also in western Texas (the area of El Paso). High level wave clouds (dark blue colour) and dissolving low level clouds (light brown/green) over Texas can also be seen.

The very short zoomed-in animated gif of three images (Figure 3) shows that the strong south-westerly winds also helped to trigger a fire, with smoke plume. The hot spot from the fire can be seen as single, dark pixel, the smoke appears as a white coloured area.

Normally, smoke is not seen in infrared images, or related infrared-based RGBs like the Dust RGB, but in this case the smoke must have had larger particles or have been mixed with dust, because it was visible.

In his 'GOES-16 loop of the day' entry Dan Lindsey, from the Cooperative Institute for Research in the Atmosphere (CIRA), wrote that the "dust from the desert southwest is advected into a line of thunderstorms over the High Plains.".

Meanwhile Scott Lindstrom, in his CIMSS Satellite Blog on this case, noted that "the visible animation from late afternoon over west Texas shows a characteristic signature of a shroud of dust around El Paso, TX behind a dryline associated with a developing cyclone in the lee of the Rocky Mountains.". Looking at all ABI channels, he wrote that "this pall of dust was visible in many of the 16 channels on the Advanced Baseline Imager (ABI) that sits on GOES-16.".