An end to the offshore Santa Ana wind regime and a change in the synoptic-scale flow pattern over the southwestern US (MODIS visible image + RUC model winds at 1 km and 2km AGL) resulted in a northward to northeastward transport of smoke from the ongoing Southern California fires on 26 October 2007. A 250-meter resolution MODIS true color image centered over the Grand Canyon in Arizona (above) shows a distinct smoke plume from a new fire that was burning along the north rim of the canyon, as well as a large amount of smoke covering the western portion of the Grand Canyon (which had been transported from the California fires).

A larger-scale MODIS true color image of the Southwest US (below) shows that the smoke from the southern California fires had spread as far as the San Joaquin Valley of California (even settling into some of the valleys along the western foothills of the Sierra Nevada Mountain Range), southern Nevada, northwestern Arizona, and extreme southwestern Utah. The IDEA MODIS Aerosol Optical Depth trajectory product from the previous day provided a fairly accurate forecast of smoke transport.