WTUS82 KCHS 061210 HLSCHS GAZ087-088-099>101-114>119-137>141-SCZ040-042>045-047>052-062015- Tropical Storm Debby Local Statement Intermediate Advisory Number 16A National Weather Service Charleston SC AL042024 810 AM EDT Tue Aug 6 2024 This product covers southeast South Carolina and southeast Georgia **DEBBY TO BRING POTENTIALLY HISTORIC AND CATASTROPHIC FLOODING TO THE AREA THIS WEEK** NEW INFORMATION --------------- * CHANGES TO WATCHES AND WARNINGS: - A Tropical Storm Warning has been issued for Dorchester, Hampton, and Inland Colleton * CURRENT WATCHES AND WARNINGS: - A Storm Surge Warning and Tropical Storm Warning are in effect for Beaufort, Charleston, Coastal Bryan, Coastal Chatham, Coastal Colleton, Coastal Jasper, Coastal Liberty, Coastal McIntosh, and Tidal Berkeley - A Tropical Storm Warning is in effect for Bulloch, Candler, Dorchester, Effingham, Evans, Hampton, Inland Berkeley, Inland Bryan, Inland Chatham, Inland Colleton, Inland Jasper, Inland Liberty, Inland McIntosh, Long, and Tattnall * STORM INFORMATION: - About 100 miles southwest of Charleston SC or about 20 miles southwest of Savannah GA - 31.9N 81.3W - Storm Intensity 45 mph - Movement Northeast or 50 degrees at 6 mph SITUATION OVERVIEW ------------------ Potentially historic rainfall totals will likely produce areas of catastrophic flooding through Thursday. Additional rainfall amounts of 10 to 15 inches is forecast over southeast South Carolina with 4 to 8 inches across southeast Georgia. This will likely result in unprecedented flooding in some areas. THIS IS A POTENTIALLY SIGNIFICANT AND LIFE THREATENING EVENT. Tropical Storm Debby is forecast to move offshore the Georgia coast and into the Atlantic later today. Debby will then meander nearby before making landfall along the South Carolina coast on Thursday. This slow motion will result in a prolonged period of significant impact across the area. A combination of fresh water flooding and storm surge will produce coastal inundation of 2 to 4 feet along the southeast Georgia and southeast South Carolina coast, especially today through Thursday. Tropical storm force wind impacts and a few tornadoes are also possible during this time, with highest chances across coastal areas. POTENTIAL IMPACTS ----------------- * FLOODING RAIN: Protect against life-threatening rainfall flooding having possible devastating impacts across southeast South Carolina and southeast Georgia. Potential impacts include: - Extreme rainfall flooding could prompt widespread rescues. As event unfolds, rescues could become impossible. - Rivers and tributaries could overwhelmingly overflow their banks in many places with deep moving water. Small streams, creeks, canals, and ditches may become raging rivers with strong currents. Flood control systems and barriers could become stressed or overwhelmed. - Flood waters will enter many structures within multiple communities, some structures becoming uninhabitable or washed away. Flood waters could render escape routes impassable. Streets and parking lots become rivers of raging water with underpasses submerged. Driving conditions become impossible and life threatening. Widespread road and bridge closures with most weakened or washed out. - Drinking water and sewer services could be negatively impacted. - Hazardous containers and materials could possibly be present in flood waters. * SURGE: Protect against life-threatening surge having possible significant impacts across coastal Georgia and coastal southeast South Carolina. Potential impacts in this area include: - Areas of inundation of saltwater along immediate shorelines and in low-lying spots farther inland near rivers and creeks, with storm surge flooding accentuated by waves. Damage to several buildings, mainly near the coast. - Sections of near-shore escape routes and secondary roads become weakened or washed out, especially in normally vulnerable low spots. - Moderate to major beach erosion with heavy surf breaching dunes. Strong and numerous rip currents. - Minor to moderate damage to marinas, docks, boardwalks, and piers. Several small craft broken away from moorings, especially in unprotected anchorages. Some navigation aids possibly displaced well off station, creating difficult navigation near inlets and waterways. Elsewhere across southeast South Carolina and southeast Georgia, little to no impact is anticipated. * WIND: Potential impacts from the main wind event are now unfolding across southeast South Carolina and southeast Georgia. Remain well sheltered from dangerous wind having possible significant impacts. If realized, these impacts include: - Some damage to roofing and siding materials, along with damage to porches, awnings, carports, and sheds. A few buildings experiencing window, door, and garage door failures. Mobile homes damaged, especially if unanchored. Unsecured lightweight objects become dangerous projectiles. - Several large trees snapped or uprooted, but with greater numbers in places where trees are shallow rooted. - Some roads impassable from large debris, and more within urban or heavily wooded places. A few bridges and access routes impassable. - Travel by vehicle or on foot increasingly difficult. Danger of death or injury from falling objects such as trees or electric wires outside. - Scattered power and communications outages, but more prevalent in areas with above ground lines, which could persist for hours or days. - Some poorly secured small craft could break loose from their moorings. * TORNADOES: Potential impacts from tornadoes are still unfolding across southeast South Carolina. Remain well braced against a tornado event having possible limited impacts. If realized, these impacts include: - Isolated tornadoes can hinder the execution of emergency plans. - Isolated locations could experience tornado damage, along with power and communications disruptions. - In isolated locations, tornadoes could damage trees, vehicles, boats and buildings, especially mobile homes and other poorly constructed structures. Elsewhere across southeast Georgia, little to no impact is anticipated. * OTHER COASTAL HAZARDS: Significant beach erosion and a high risk of powerful and dangerous rip currents can be expected this week. PRECAUTIONARY/PREPAREDNESS ACTIONS ---------------------------------- * EVACUATIONS: Follow the advice of local officials. * OTHER PREPAREDNESS INFORMATION: If a tornado warning is issued for your area, quickly move to the safest place within your shelter. Protect your head and body. Rapidly rising flood waters are deadly. If you are in a flood-prone area, consider moving to higher ground. Never drive through a flooded roadway. Remember, turn around don't drown! Closely monitor weather.gov, NOAA Weather radio or local news outlets for official storm information. Be ready to adapt to possible changes to the forecast. Ensure you have multiple ways to receive weather warnings. * ADDITIONAL SOURCES OF INFORMATION: - For information on appropriate preparations see ready.gov - For information on creating an emergency plan see getagameplan.org - For additional disaster preparedness information see redcross.org NEXT UPDATE ----------- The next local statement will be issued by the National Weather Service in Charleston SC around 12 PM EDT, or sooner if conditions warrant. $$