This loop of GOES-8 InfraRed (IR) temperature difference product shows the development of several large plumes of blowing dust/sand (yellow to blue enhancement) over northern Mexico and the southwestern U.S. on 21 January 1999. Differences in emissivity of the fairly large silicate particles at 10.7 versus 12.0 microns yields a difference in brightness temperature when comparing these two IR channels.
Surface reports of horizontal visibility (black, in miles) and restriction to visibility (red, BD=blowing dust, BN=blowing sand, H=haze, F=fog, RW=rain shower) are also plotted on the images. Note how the visibility over southwest Texas decreases rapidly as the airborne dust and sand overspreads that region.