The Western United States is bracing for a significant weather shift as Pacific storms move in to break a record-breaking heat wave. According to Maven's Notebook, regions like California, northern Nevada, southern Oregon, and Idaho, which have been experiencing unprecedented high temperatures, are expected to see cooler conditions starting Tuesday. These storms, originating from the Pacific Ocean, will bring a combination of rain and mountain snow. While steady rainfall may not reach the southernmost areas consistently, much of Nevada is likely to experience sporadic showers.