Tropical Storm — Cameron, Texas

2020-07-25 to 2020-07-26 · Cameron, Texas

Event narrative

Tropical Storm-force winds ravaged northern Cameron County from mid afternoon on July 25th until just after midnight on July 26th. Strongest winds occurred during the evening of July 25th, when the southern and eastern eyewall clipped the region along and north of Interstate 2 between Harlingen/Rio Hondo and La Feria north to the Willacy County line. Measured and estimated wind gusts in these areas were near hurricane force (65 mph) with sustained winds peaking between 40 and 50 mph. Harlingen/Rio Grande Valley International Airport reported a peak gust to 63 mph before taking a power loss.

The slow movement of the inner core of Hanna allowed minor wind damage to occur in this area, with at least one hundred trees losing large limbs along with power lines and several power poles snapped or bent. Minor damage also occurred to poorly built structures along the IH-2 corridor as well as along the IH-69E corridor from Harlingen/San Benito northward. This included a number of fences blown down and a roof blown off a shed near La Feria. At the storm's peak, an estimated 50 thousand electric customers were without power. NCEI's total dollar damage estimate (divided among the affected counties by local storm data experts) was $99.75 million for inland Cameron County. Public Assistance dollar values were estimated to be $1.88 million.

Crop damage was also significant, with sugar cane snapped in many fields and young fruit being blown off citrus trees, which also sustained damage. Estimated dollar value loss based on reports from Texas Agrilife in late summer was $25.9 million in Cameron County.

Wider weather episode

Hurricane Hanna, the 2020 Atlantic season's first Hurricane, made landfall along the unpopulated Padre Island National Seashore on the mid-Kenedy County coastline as a Category 1 storm at around 5 PM Central Time Saturday, July 25th, carrying sustained 90 mph winds with gusts over 100 mph in a small portion of the inner eye wall. The hurricane spun slowly but steadily into southern Kenedy and northern Hidalgo County through just after midnight on the 26th, then through Starr County as a Tropical Storm before moving into Tamaulipas before daybreak and eventually near Monterrey, Nuevo Leon, by noon before dissipating during the evening of the 26th. Following the passage of the inner eye wall, broad feeder bands of torrential rains and gusty tropical storm force winds continued through the mid to late morning hours of July 26th, slowly migrating from east to west across the populated Rio Grande Valley.

Other than storm surge flooding, which peaked just north of Baffin Bay on the Kleberg and Nueces County coast near Corpus Christi, Hanna's memory for the Rio Grande Valley will be flooding rainfall, power outages, and an array of damage to poorly constructed buildings, from minor roof damage to complete demolition. Between 8 and 15 inches of rain fell from Port Mansfield to Harlingen, and along Interstate Highway 2 out through Mission and Sullivan City. The combination of high rainfall, locally high rainfall rates, and poor drainage left between 18 inches and four feet of water depth in many areas, most commonly from western Cameron through southeastern Hidalgo County, as well as a separate pocket in the Mission/La Joya/Sullivan City area. The rainfall wiped out 95% of the region's cotton crop; the combination of crop loss and production loss was more than one third of a billion dollars alone ($366 million)...most of which was in the Rio Grande Valley region.

At the peak of the storm, 250 thousand electric customers were without power, including all of Willacy County. Though storm surge was cut short by strong westerly flow across Cameron County, radiating swells did produce a notable surge of 3 feet or greater (estimated) from near Port Mansfield through Kenedy County. When the damage and economic loss is counted to infrastructure and agriculture combined, it is likely that Hanna cost at least one billion dollars across the Rio Grande Valley and the Deep S. Texas ranch country.

Source: NOAA Storm Events Database, event_id 914160. Narrative written by the NWS forecast office that issued the report.