National Weather Service offices issued widespread heat advisories, extreme heat warnings, and localized flood watches across multiple U.S. regions on July 3 ahead of Fourth of July conditions. Offices including NWS Louisville KY, Baltimore/Washington DC, Jackson MS, AKQ (for Maryland beaches and eastern Currituck), GYX (New Hampshire coastal zones), AMA (Texas/OK panhandle counties), and many regional forecast offices continued or extended Heat Advisories through July 4, generally until late evening between 8:00 and 9:00 PM EDT. Forecast details posted by offices included heat index values reaching 112 in one report, common heat indices of 100 to 104 in portions of Maryland and Virginia, and values up to 105 in parts of Mississippi. Several advisories covered large lists of counties, for example Jackson MS named Bolivar, Sunflower, Leflore and more, while AMA listed Dallam, Deaf Smith, Hansford and other panhandle counties. Some areas saw Extreme Heat Warnings downgraded to Heat Advisories, and multiple offices posted expirations or continuations of advisories as conditions evolved through the holiday period. Thunderstorm and flood-watch mentions accompanied some heat products, indicating overlapping heat and heavy-rain hazards for parts of the country into July 4 evening.
