WTUS82 KCHS 041523 HLSCHS GAZ087-088-099>101-114>119-137>141-SCZ040-042>045-047>052-042330- Tropical Storm Debby Local Statement Advisory Number 9 National Weather Service Charleston SC AL042024 1123 AM EDT Sun Aug 4 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 Watch has been issued for Evans and Tattnall * CURRENT WATCHES AND WARNINGS: - A Storm Surge Watch and Tropical Storm Watch are in effect for Beaufort, Charleston, Coastal Bryan, Coastal Chatham, Coastal Colleton, Coastal Jasper, Coastal Liberty, Coastal McIntosh, and Tidal Berkeley - A Tropical Storm Watch is in effect for Evans, Inland Berkeley, Inland Bryan, Inland Chatham, Inland Jasper, Inland Liberty, Inland McIntosh, Long, and Tattnall * STORM INFORMATION: - About 480 miles southwest of Charleston SC or about 400 miles south-southwest of Savannah GA - 27.0N 84.3W - Storm Intensity 65 mph - Movement North-northwest or 330 degrees at 13 mph SITUATION OVERVIEW ------------------ The center of Tropical Storm Debby is expected to continue to strengthen as it moves northward through the eastern Gulf of Mexico today, before making landfall as a hurricane in the Big Bend region of Florida on Monday. Debby is then forecast to move northeast across Southeast Georgia Tuesday morning and emerge off of the Georgia coast Tuesday night or Wednesday morning while slowing down. Debby will stall over or near the area through at least mid week, resulting in prolonged impacts. This includes multiple periods of flooding rainfall, coastal inundation and tropical storm-force wind gusts, starting late tonight and continuing through Thursday. There is an increasing possibility for historic and potentially catastrophic rainfall amounts of 10 to 20 inches, with local amounts approaching 30 inches. The highest rainfall totals will occur across coastal South Carolina and Georgia, including the Charleston and Savannah metropolitan areas. If these rainfall totals are realized, widespread severe flash flooding will occur. THIS IS A POTENTIALLY SIGNIFIANT AND LIFE THREATNING EVENT. Storm surge inundation of 2 to 4 feet is possible along the Southeast Georgia and Southeast South Carolina coast, especially Tuesday through Thursday. In addition, isolated tornadoes will be possible, with highest chances across coastal areas. POTENTIAL IMPACTS ----------------- * FLOODING RAIN: Prepare for 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: Prepare for life-threatening surge having possible significant impacts across coastal Georgia and south coastal 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. * WIND: Prepare for dangerous wind having possible significant impacts across mainly coastal portions of Southeast South Carolina and Southeast Georgia. Potential impacts in this area 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: Prepare for a dangerous tornado event having possible significant impacts across coastal South Carolina and Georgia. Potential impacts include: - Isolated to scattered tornadoes can hinder the execution of emergency plans. - Scattered locations could experience enhanced damage due to tornadoes with a few spots of considerable damage, power loss, and communications failures. - Scattered locations could realize roofs torn off frame houses, mobile homes demolished, boxcars overturned, large trees snapped or uprooted, vehicles tumbled, and small boats tossed about. * OTHER COASTAL HAZARDS: Significant beach erosion and an elevated risk for powerful and dangerous rip currents can be expected this week. PRECAUTIONARY/PREPAREDNESS ACTIONS ---------------------------------- * EVACUATIONS: Follow the advice of local officials. * OTHER PREPAREDNESS INFORMATION: Now is the time to check your emergency plan and emergency supplies kit and take necessary actions to protect your family and secure your home or business. If you live in a place particularly vulnerable to flooding, such as near the ocean or a large inland lake, in a low-lying or poor drainage area, in a valley, or near an already swollen river, plan to move to safe shelter on higher ground. Always heed the advice of local officials and comply with orders that are issued. Do not needlessly jeopardize your life or the lives of others. When securing your property, outside preparations should be concluded as soon as possible before conditions deteriorate. The onset of strong gusty winds or flooding can cause certain preparedness activities to become unsafe. Closely monitor weather.gov, NOAA Weather Radio and local news outlets for official storm information. Listen for possible changes to the forecast. There is a threat from tornadoes with this storm. Have multiple ways to receive Tornado Warnings. Be ready to shelter quickly. * 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 6 PM EDT, or sooner if conditions warrant. $$ ST