Hurricane Harvey Local Statement Intermediate Advisory Number 18A National Weather Service Houston/Galveston TX AL 092017
7:07 p.m. CDT Thursday, August 24, 2017
This product covers Southeast Texas (including Montgomery County)
**HARVEY HEADED TOWARDS THE TEXAS COAST**
**DEVASTATING FLOODING BECOMING LIKELY FOR SOUTHEAST TEXAS**
* CHANGES TO WATCHES AND WARNINGS:
* CURRENT WATCHES AND WARNINGS:
– A Tropical Storm Warning and Storm Surge Watch are in effect for Chambers and Harris
– A Tropical Storm Warning is in effect for Austin, Colorado, Fort Bend, Liberty, Waller, and Wharton
– A Storm Surge Warning and Hurricane Warning are in effect for Jackson and Matagorda
– A Storm Surge Warning and Tropical Storm Warning are in effect for Brazoria and Galveston
* STORM INFORMATION:
– About 300 miles south of Galveston TX or about 270 miles south-southeast of Port O`Connor TX
– 25.0N 94.3W
– Storm Intensity 85 mph
– Movement Northwest or 325 degrees at 10 mph
Harvey has intensified into a hurricane this afternoon. Harvey is expected to continue to strengthen possibly becoming a major hurricane on Friday before landfall. At this point, Harvey could become a high end category 3 hurricane. The primary impact from Harvey remains very heavy rainfall and extreme flooding for southeast Texas. There is also the threat for tropical storm to hurricane force winds and storm surge along the coast. The most likely arrival time for tropical storm force winds to reach the upper Texas coast is during the day on Friday.
Since the wind fields have expanded in Harvey, higher storm surge can be expected up the Texas coast. Again, we want to emphasize the high amounts of rainfall that could lead to widespread and prolonged flooding across the area.
* FLOODING RAIN:
Prepare for life-threatening rainfall flooding having possible devastating impacts across much of southeast Texas. The highest threat is for areas along and south of a Columbus to Houston line. Potential impacts include:
– Extreme rainfall flooding may prompt numerous evacuations and rescues.
– Rivers and tributaries may overwhelmingly overflow their banks in many places with deep moving water. Small streams, creeks, canals, and ditches may become raging rivers. Flood control systems and barriers may become stressed.
– Flood waters can enter numerous structures within multiple communities, some structures becoming uninhabitable or washed away. Numerous places where flood waters may cover escape routes. Streets and parking lots become rivers of raging water with underpasses submerged. Driving conditions become very dangerous. Numerous road and bridge closures with some weakened or washed out.
Prepare for life-threatening rainfall flooding having possible limited to extensive impacts across areas north of Columbus to Houston.
Prepare for life-threatening wind having possible devastating impacts across Matagorda Bay from Port O`Connor to Sargent. Potential impacts in this area include:
– Structural damage to sturdy buildings, some with complete roof and wall failures. Complete destruction of mobile homes. Damage greatly accentuated by large airborne projectiles. Locations may be uninhabitable for weeks or months.
– Numerous large trees snapped or uprooted along with fences and roadway signs blown over.
– Many roads impassable from large debris, and more within urban or heavily wooded places. Many bridges, causeways, and access routes impassable.
– Widespread power and communications outages.
Prepare for life-threatening surge having possible devastating impacts across the entire Upper Texas Coast. Potential impacts in this area include:
– Widespread deep inundation, with storm surge flooding greatly accentuated by powerful battering waves. Structural damage to buildings, with many washing away. Damage greatly compounded from considerable floating debris. Locations may be uninhabitable for an extended period.
– Near-shore escape routes and secondary roads washed out or severely flooded. Flood control systems and barriers may become stressed.
– Extreme beach erosion. New shoreline cuts possible.
– Massive damage to marinas, docks, boardwalks, and piers. Numerous small craft broken away from moorings with many lifted onshore and stranded.
Also, prepare for life-threatening surge having possible significant to extensive impacts across Galveston Bay.
Prepare for a tornado event having possible limited impacts across all of southeast Texas. Potential impacts include:
– The occurrence of isolated tornadoes can hinder the execution of emergency plans during tropical events.
– A few places may experience tornado damage, along with power and communications disruptions.
– Locations could realize roofs peeled off buildings, chimneys toppled, mobile homes pushed off foundations or overturned, large tree tops and branches snapped off, shallow-rooted trees knocked over, moving vehicles blown off roads, and small boats pulled from moorings.
Elsewhere across Southeast Texas, little to no impact is anticipated.
WATCH/WARNING PHASE – For those under evacuation orders, leave as soon as practical with a destination in mind. Gas up your vehicle well ahead of time. Be sure that you take all essential materials from your emergency supplies kit. Let others know where you are going and when you intend to arrive.
WATCH/WARNING PHASE – If evacuating the area, stick to prescribed evacuation routes. Look for additional traffic information on roadway
smart signs and listen to select radio channels for further travel instructions. Drivers should not use cell phones while operating vehicles.
WATCH/WARNING PHASE – For those not under evacuation orders, understand that there are inherent risks to evacuation (such as traffic congestion, accidents, and driving in bad weather), so evacuate only if necessary. Help keep roadways open for those that are under evacuation orders.
WATCH/WARNING PHASE – If you are exceptionally vulnerable to wind or water hazards from tropical systems, consider voluntary evacuation,
especially if being officially recommended. Relocate to a predetermined shelter or safe destination.
WATCH/WARNING PHASE – If evacuating away from the area or relocating to a nearby shelter, leave early before weather conditions become hazardous.
* OTHER PREPAREDNESS INFORMATION:
Now is the time to check your emergency plan and take necessary actions to secure your home or business. Deliberate efforts should be underway to protect life and property. Ensure that your Emergency Supplies Kit is stocked and ready.
When making safety and preparedness decisions, do not focus on the exact forecast track as there are inherent forecast uncertainties which must be taken into account.
If you live in a place that is particularly vulnerable to high wind, such as a mobile home, an upper floor of a high rise building, or on a boat, plan to move to safe shelter. Take enough supplies for you and your family for several days.
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 canyon, 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 any orders that are issued. Do not needlessly jeopardize your life or the lives of others.
When securing your property, outside preparations should be conducted as soon as possible before conditions deteriorate. The onset of strong gusty winds and heavy rain can cause certain preparedness activities to become unsafe.
Be sure to let friends and other family members know of your intentions and whereabouts for surviving the storm. For emergency purposes, have someone located away from the threatened area serve as your point of contact. Share vital contact information with others.
Keep cell phones handy and well charged.
Be a Good Samaritan and check on those who may not be fully aware of the situation or who are unable to make personal preparations.
Visitors to the area should become familiar with nearby surroundings.
If you are a visitor, know the name of the county or parish in which you are located and where it is relative to current watches and warnings. If staying at a hotel, ask the management staff about their onsite disaster plan. Listen for evacuation orders, especially pertaining to area visitors.
Closely monitor NOAA Weather Radio or MCPR (this website) for official storm information. Listen for possible changes to the forecast.
* 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
———–The next local statement will be issued by the National Weather Service in Houston/Galveston TX around 1030 PM CDT, or sooner if conditions warrant.