Atmospheric patterns on September 12, 2026, featured scattered thunderstorms and showers across the Southeast from Alabama through the Carolinas and into Virginia, driven by moisture and instability with localized heavy rainfall possible, according to National Weather Service observations. Steadier rain developed in the mid-Atlantic during the afternoon and overnight, while additional storms affected the Gulf Coast, Rockies, and areas from Wisconsin to Arkansas. A Pacific Northwest system brought showers and thunderstorms there, contrasting with drier conditions across much of the Northeast and parts of the West. Official climate summaries from sites including Charlotte, Washington DC, and San Francisco confirm measurable precipitation concentrated in the Southeast and mid-Atlantic corridors, with trace or zero amounts elsewhere. Model guidance and surface observations from NOAA stations highlighted these regional contrasts tied to frontal boundaries and low-pressure influences.