PHOENIX -- Firefighters are concerned about new wildfires igniting in the Southwest during the hot, dry weekend.
National Interagency Fire Center spokeswoman Jennifer Smith says crews are especially worried about wildfires igniting in the Four Corners region where the borders of Colorado, New Mexico, Utah and Arizona intersect.
She says some of the strongest parts of a high pressure system are expected to be parked over the area through the weekend, where forecasters are calling for lightning but little to no precipitation.
Scientists say that the jet stream, the river of air that dictates weather patterns, has been more erratic in the past few years. It's responsible for weather systems getting stuck, like the current heat wave. Scientists disagree on whether global warming is the cause of the jet stream's behavior.