Coastal Flood Advisory: Dangerous High Tides and Storm Surge Threaten U.S. Coast—What You Need to Know

Washington, D.C. — Coastal communities up and down the Atlantic seaboard are under a coastal flood advisory today as a surge of tropical moisture, high astronomical tides and persistent onshore winds converge to raise water levels and dump torrential rain. WHERE THE ADVISORIES ARE IN FORCE • District of Columbia and the tidal Potomac/upper Chesapeake: The NWS has issued a Flood Watch from 2 p.m. to midnight with rainfall rates up to two inches per hour and minor tidal inundation expected along Wharf Street, the Navy Yard Riverwalk and low-lying stretches of Old Town Alexandria. • Cape Fear region, N.C.: An updated coastal flood advisory covers Inland New Hanover County, including downtown Wilmington and Battleship Road, through 4 a.m. Tuesday, where up to half a foot of salt-water inundation is possible. • South Florida: A separate Flood Watch runs from 2 p.m. to 11 p.m. for Palm Beach, Broward and Miami-Dade counties, with widespread three-inch totals and isolated seven-inch downpours forecast as a slow-moving low crosses the peninsula. WHAT’S DRIVING THE FLOOD THREAT A weak surface low over central Florida is funneling deep Gulf and Atlantic moisture northward while high pressure offshore forces winds to pile water against the coastline. At the same time, July’s perigean (“king”) tides are already running 6–10 inches above normal. The overlap of peak tide this evening and rounds of thunderstorms greatly increases the risk of high-tide flooding in tidal creeks, back bays and urban storm-drain systems. TIMING & IMPACTS • Peak inundation: 8 p.m.–11 p.m. local time along most East Coast tide gauges. • Expected water rise: 0.5–1 ft above ground in typically vulnerable spots; localized 1–2 ft where heavy rain coincides with high tide. • Roads to monitor: Water Street in Wilmington, Wharf Street in Washington, Flagler Drive in West Palm Beach, and any marina parking lots or underpasses bordering tidal rivers and canals. • Additional hazards: Isolated 40–60 mph gusts and frequent cloud-to-ground lightning inside stronger cells; scattered power outages where saturated soils topple shallow-rooted trees. SAFETY & PREPAREDNESS TIPS • Turn Around, Don’t Drown: only six inches of flowing water can knock an adult off their feet, and a foot can sweep away most cars. • Secure loose dock lines, kayaks and trash bins before evening high tide. • If you live in a flood-prone zone, move vehicles to higher ground and keep a go-bag with medication, chargers and IDs. • Never drive around barricades; the road beneath could be washed out. OUTLOOK Models show the low sliding into the eastern Gulf Tuesday, but lingering onshore flow may keep a coastal flood advisory in effect for Mid-Atlantic bays through midweek. Residents should monitor NWS updates and local emergency-management alerts for any upgrades to Coastal Flood Warning status or flash-flood warnings tied to heavier rain bands. Bottom line: today’s coastal flood advisory is a reminder that minor, “nuisance” flooding can turn dangerous quickly when heavy rain meets an already swollen tide cycle. Stay weather-aware, plan travel outside tonight’s high-tide window, and be ready to move to higher ground if water starts to rise.