Severe Severe Storm ● Closed

Special Marine Warning — Tidal Potomac from Key Bridge to Indian Head MD; Tidal Potomac from Indian Head to Cobb Island MD

Event time: Aug 20, 2026 22:20 UTC Last updated: Sep 6, 2026 United States

Icon = what happened · ring colour = how serious: Extreme Severe Moderate Minor

Loading live data… · Marker positions are approximate; severity is labelled in each popup. Sources: USGS, GDACS, NASA EONET, NOAA/NWS, EMSC.

Special Marine Warning issued August 20 at 6:20PM EDT until August 20 at 6:30PM EDT by NWS Baltimore MD/Washington DC

Measurements

Coordinates	38.7012, -77.1400
Region	Tidal Potomac from Key Bridge to Indian Head MD; Tidal Potomac from Indian Head to Cobb Island MD
Expires	2026-08-20T18:30:00-04:00
Nws Urgency	Immediate
Nws Certainty	Likely

Official source

Weather alert data courtesy of NOAA / National Weather Service

This is an official warning issued by the authority named above. Follow its instructions and those of your local emergency services.

Severity as published by US National Weather Service.

View original report

This event as JSON · API and licence

Source updated 60 days ago (Aug 20, 2026 22:28 UTC) · we last heard from US National Weather Service 39 seconds ago

On a slow connection? Low-bandwidth version — no map, no scripts, under 14 KB.

Official authorities in United States

If you are there, these are the bodies whose instructions apply. This site is not an emergency service and does not issue warnings.

More for United States →

Earlier severe storm events in United States

Severe and extreme events of the same kind, before this one. Listed for scale, not because they are connected to it.

Severe Thunderstorm Warning — Butler, KY; Logan, KY; Warren, KY Severe Severe Storm United States closed via NWS Jul 21, 2026 Severe Thunderstorm Warning — Cochise, AZ Severe Severe Storm United States closed via NWS Jul 21, 2026 Severe Thunderstorm Warning — Muhlenberg, KY Severe Severe Storm United States closed via NWS Jul 21, 2026 Severe Thunderstorm Warning — Butler, KY; Edmonson, KY; Warren, KY Severe Severe Storm United States closed via NWS Jul 21, 2026

Nearby & related events

Special Marine Warning — Chesapeake Bay from Smith Point to Windmill Point VA; Chesapeake Bay from Windmill Point to New Point Comfort VA; Chesapeake Bay from New Point Comfort to Little Creek VA; Chesapeake Bay from Little Creek VA to Cape Henry VA Severe Severe Storm United States monitoring via NWS 2 days ago Special Marine Warning — Tidal Potomac from Indian Head to Cobb Island MD; Tidal Potomac from Cobb Island MD to Smith Point VA Severe Severe Storm United States monitoring via NWS 2 days ago Special Marine Warning — Tidal Potomac from Indian Head to Cobb Island MD; Tidal Potomac from Cobb Island MD to Smith Point VA Severe Severe Storm United States monitoring via NWS 2 days ago Special Marine Warning — Delaware Bay waters north of East Point NJ to Slaughter Beach DE Severe Severe Storm United States monitoring via NWS 2 days ago Special Marine Warning — Chesapeake Bay from North Beach to Drum Point MD; Chesapeake Bay from Drum Point MD to Smith Point VA; Tidal Potomac from Indian Head to Cobb Island MD; Tidal Potomac from Cobb Island MD to Smith Point VA; Choptank River to C Severe Severe Storm United States monitoring via NWS 2 days ago

Disclaimer: figures are automatic feeds from the named agencies and may be revised. Do not use this page for life-safety decisions — follow official local emergency services.