Tropical Storm — Willacy, Texas

2010-09-06 to 2010-09-07 · Willacy, Texas

Event narrative

After ripping Harlingen's Valley International Airport with 72.5 mph wind gusts just prior to midnight CST (6 miles south of the Cameron/Willacy county line, the inner core of Hermine waned for a few moments before reintensifying in southern Willacy County, ultimately slamming through Raymondville at around 1 AM with wind gusts estimated just below hurricane force (70 mph). Widespread damage included hundreds of snapped limbs, dozens of uprooted trees, power outages to 75 to 80 per cent of the county, and destruction of several poorly constructed roofs and lean'tos. At one home, a trampoline sailed into a window, causing a scratch injury to a 5 year old girl. At a motor hotel along the expressway, roof decking was blown out, forcing 10 guests to escape the facility. Significant injuries were not reported, though at least one of the guests had minor scratches.

Damage was also noted to a few poorly constructed aluminum barns and surrounding trees in south central Willacy County, from 5 miles east of Lyford down FM 507 to near Santa Monica close to the Cameron County line.

AEP Texas reported 4400 customers without power during the peak of the storm.

Wider weather episode

A persistent are of showers and thunderstorms over the extreme southwestern Gulf of Mexico east of the City of Veracruz, Mexico, during the early morning hours of Sunday, September 5th, 2010, gradually organized into Tropical Depression Number 10 shortly after sunset. Convection increased overnight on the 5th and into the early morning hours of Monday, September 6th, as the system began moving northward, and Tropical Storm Hermine was born at 4 AM CDT on the 6th. Hermine tracked steadily north'northwestward while gradually intensifying on the 6th, reaching the coast of northeastern Tamaulipas State, Mexico, about 40 miles south of Brownsville at 830 PM CDT with peak sustained winds estimated at 65 mph.

Hermine would track to the north'northwest at a steady 14 mph, with the center of circulation crossing the Rio Grande near Los Indios (Cameron County) at around midnight on Tuesday, September 7th. The center reached Harlingen at around 1 AM, Raymondville at around 2 AM, and progressed through the west portion of the King Ranch before exiting Deep South Texas near Falfurrias at around 5 AM. During that time, peak 1 minute sustained winds around the east periphery of the cyclone lessened only slightly, falling from 60 to 50 mph.

A swath of damaging winds and flooding rains pounded Brownsville, Harlingen, and Raymondville as the eyewall of Hermine tracked along and east of Federal Highway 77 in Cameron and Willacy Counties. Peak wind gusts reached or exceeded 70 mph, causing widespread damage to trees and power lines. Rainfall of more than 3 inches in just a few hours flooded roads and farmland, especially in a small swath from northeast Cameron County to southern Willacy County. More than 250,000 residents were impacted by the core of Hermine during the middle of the night, making for a memorable end to the Labor Day weekend. The rapid movement and small core did not allow enough water to build up to a true storm surge in Cameron and Willacy County; tide departures peaked around 1.5 feet which produced run-up to the dune line and closed the county beach access points on South Padre Island to vehicular traffic.

Hermine's near-hurricane force gust punch knocked down hundreds of tree limbs, tore off a number of roofs, blew down dozens of fences, and knocked power out to more than 55,000 area residents during the peak of the storm. In all, several millions of dollars in damage likely occurred to structures in the path of the core circulation of Hermine, including the inner eye wall and next level of core circulation on the east side of the center, which produced tropical storm force winds toward the coastline and into the Lower Texas Gulf waters. A federal emergency was declared for Cameron, Willacy, and Kenedy County based on initial impacts. Final damage statistics will be available later in autumn, 2010.

Source: NOAA Storm Events Database, event_id 251973. Narrative written by the NWS forecast office that issued the report.