A flooding catastrophe is expected in Texas as Hurricane Harvey nears the Lone Star State. A plethora of deadly weather dangers are bearing down on the Gulf Coast state as people continue their evacuation efforts from the coast. The storm is forecast by the National Hurricane Center (NHC) to make landfall on the Texas coast late Friday as a major hurricane; it will be the first major hurricane to strike the United States in 4,323 days. Harvey is forecast to strike land as a strong Category 3 hurricane or perhaps as strong as a Category 4 storm; both have the potential to create complete devastation at the point of landfall. While an enormous storm surge is also expected along the coast, extremely heavy, epic rains will flood the state, with 25-35″ of rain possible.
Ahead of this storm, the National Hurricane Center has issued Storm Surge Warnings and Watches for portions of the Texas coast. This is the first time Storm Surge Warnings/Watches have become operational for a storm. A Storm Surge Warning is in effect for Port Mansfield to High Island, Texas while a Storm Surge Watch is in effect for south of Port Mansfield,Texas to the Mouth of the Rio Grande. A Storm Surge Warning means there is a danger of life-threatening inundation, from rising water moving inland from the coastline, during the next 36 hours in the indicated locations. The National Hurricane Center warnings; “This is a life-threatening situation. Persons located within these areas should take all necessary actions to protect life and property from rising water and the potential for other dangerous conditions. Promptly follow evacuation and other instructions from local officials.” A Storm Surge Watch means there is a possibility of life-threatening inundation, from rising water moving inland from the coastline, in the indicated locations during the next 48 hours.
A Hurricane Warning is in effect for Port Mansfield to Sargent, Texas. A Tropical Storm Warning is in effect for the area north of Sargent to High Island, Texas and south of Port Mansfield, Texas to the Mouth of the Rio Grande. A Hurricane Watch is in effect for south of Port Mansfield Texas to the Mouth of the Rio Grande while a Tropical Storm Watch is in effect for south of the Mouth of the Rio Grande to Boca de Catan, Mexico. A Hurricane Warning means that hurricane conditions are expected somewhere within the warning area. A warning is typically issued 36 hours before the anticipated first occurrence of tropical-storm-force winds, conditions that make outside preparations difficult or dangerous. The National Hurricane Center cautions that preparations to protect life and property should be rushed to completion. A Hurricane Watch means that hurricane conditions are possible
within the watch area.
The NHC also says that interests in southwestern Louisiana should continue to monitor the progress of this system; additional advisories may be required there over time.
Hurricane Harvey is currently moving toward the northwest near 10 mph. This general motion is expected to continue with a decrease in forward speed during the next couple of days. On the forecast track, Harvey will approach the middle Texas coast on Friday and make landfall Friday night or early Saturday. Harvey is then likely to stall near or just inland of the middle Texas coast through the weekend.
Reports from an Air Force Reserve Hurricane Hunter aircraft indicate that maximum sustained winds remain near 85 mph with higher gusts. While Hurricane Harvey has changed little in strength over the past few hours, strengthening is expected to resume during the next few hours, and Harvey is expected to become a major hurricane by Friday before it reaches the middle Texas coast.
Hurricane-force winds extend outward up to 25 miles from the center, and tropical-storm-force winds extend outward up to 90 miles.
The minimum central pressure just reported by the Hurricane Hunter Aircraft is 974 mb (28.76 inches).
There are numerous hazards that will impact land as Harvey approaches: incredible rainfall and flooding, storm surge, destructive winds, dangerous surf, and tornadoes.
Harvey is expected to produce total rain accumulations of 15 to 25 inches and isolated maximum amounts of 35 inches over the middle and upper Texas coast through next Wednesday. During the same time period Harvey is expected to produce total rain accumulations of 7 to 15 inches in far south Texas and the Texas Hill Country over through central and southwest Louisiana, with accumulations of up to 7 inches extending into other parts of Texas and the lower Mississippi Valley. Rainfall from Harvey will cause devastating and life-threatening flooding.
The combination of a dangerous storm surge and the tide will cause normally dry areas near the coast to be flooded by rising waters moving inland from the shoreline. The water is
expected to reach the following heights above ground if the peak surge occurs at the time of high tide:
- North Entrance Padre Island National Seashore to Sargent…6 to 12 ft
- Sargent to Jamaica Beach…5 to 8 ft
- Port Mansfield to North Entrance Padre Island National Seashore…5 to 7 ft
- Jamaica Beach to High Island…2 to 4 ft
- Mouth of the Rio Grande to Port Mansfield…2 to 4 ft
- High Island to Morgan City…1 to 3 ft
The deepest water will occur along the immediate coast near and to the northeast of the landfall location, where the surge will be accompanied by large and destructive waves. Surge-related flooding depends on the relative timing of the surge and the tidal cycle, and can vary greatly over short distances. For information specific to your area, please see products issued by your local National Weather Service forecast office.
Hurricane conditions are likely within the hurricane warning area late Friday or Friday night, with tropical storm conditions expected to first reach the coast in the hurricane warning area Friday. In Category 3 hurricanes, well-built framed homes may incur major damage or removal of roof decking and gable ends. Many trees will be snapped or uprooted, blocking numerous roads. Electricity and water will be unavailable for several days to weeks after the storm passes. In Category 4 hurricanes, catastrophic damage will occur. Well-built framed homes can sustain severe damage with loss of most of the roof structure and/or some exterior walls. Most trees will be snapped or uprooted and power poles downed. Fallen trees and power poles will isolate residential areas. Power outages will last weeks to possibly months. Most of the area will be uninhabitable for weeks or months.
Swells generated by Harvey are likely to affect the Texas, Louisiana, and northeast Mexico coasts by Friday. These swells are likely to cause life-threatening surf and rip current conditions.
Isolated tornadoes are possible across portions of the middle and upper Texas coast on Friday.
Residents in or near watch/warning areas for Tropical Storm Harvey should act on their hurricane action plans. People along any Gulf or Atlantic coastline, and Hawaii, should be prepared every hurricane season; with Harvey here, people should ensure they are ready for the arrival of a potential disaster wherever they may be.
Experts believe this Atlantic Hurricane Season, which runs through to the end of November, will be a busy one. Dr. Phil Klotzbach and the experts at Colorado State University updated their seasonal outlook again on July 5, showing a much more active than normal season expected. The National Oceanic and Atmospheric Administration (NOAA) also released their own forecast which shows this hurricane season to be likely more active than others.