Scattered to widespread showers, below normal temperatures, and isolated to scattered thunderstorms are likely across much of northern California, Oregon, and far northwest Nevada as an upper low slowly drifts south over northern California. Heavy rain and debris flows on recent burn scars are possible in northwest California. Dry and breezy conditions will continue along the eastern Sierra and develop on portions of the southern and central High Plains into the southern Rockies. A deep monsoonal surge will push northward, with scattered to widespread mostly wet thunderstorms from Arizona through much of the central and eastern Great Basin into western Colorado, western Wyoming, central Idaho, and southwest Montana. Some of the thunderstorms are likely to be severe and produce heavy rain. Hot and dry conditions will remain from the Lower Mississippi Valley into Texas and on much of the southern and central Plains, while scattered to widespread thunderstorms are likely again along the central and Florida Gulf Coasts into the Deep South. Scattered to widespread precipitation will continue across much of Alaska, while trade winds will weaken somewhat from yesterday on the Hawai’ian Islands.