Erin (2007)

A broad low that began as a tropical wave off Africa on 3 August organized slowly over the Caribbean and Gulf of Mexico and became Tropical Depression Five at 0000 UTC on 15 August 2007 about 375 n mi east-southeast of Brownsville, Texas. It strengthened to Tropical Storm Erin later that day and moved northwestward across the central Gulf. Erin was a short-lived tropical storm from 15–16 August, weakened to a depression before reaching the Texas coast on 16 August, and its low-level remnant tracked inland across Texas into Oklahoma and then northeastward before dissipating on 20 August.

Erin’s center made landfall on San Jose Island, Texas (just north of Port Aransas, about 30 nmi east-northeast of Corpus Christi) at about 1030 UTC on 16 August as a tropical depression with maximum winds of about 30 kt (35 mph equivalent surface winds are the tropical-storm peak). No other coastal landfalls as a tropical cyclone were recorded; the system’s remnant low moved into Oklahoma on 19 August where it produced a brief period of strong winds and organized convection but was not reclassified as a tropical cyclone.

The peak intensity while Erin was a tropical cyclone was 35 kt (40 mph) with a minimum measured central pressure near 1003 mb during 15–16 August. When the remnant low intensified briefly over Oklahoma on 19 August, surface observations support a maximum near 50 kt (about 58 mph) and an estimated minimum pressure of 995 mb at 0600 UTC that day, but NHC did not classify that episode as a tropical cyclone.

Storm surge and rainfall caused the primary coastal and inland impacts. About three feet of surge was observed in the Galveston area on the day of Texas landfall. Heavy rains of 3–7 inches were common across southeastern, south-central, and western Texas, parts of Oklahoma, and southern Missouri, with numerous locations receiving more than 10 inches. Notable measured totals include over 9 inches near Watonga, Oklahoma (Mesonet site and other unofficial reports up to ~11 in), and multiple Houston-area bayous and gauges showing several feet of flooding (for example Hunting Bayou/Lockwood area depths reported around 9–10 ft at some locations above normal channel levels).

Erin and its remnants caused a total of 16 direct fatalities: nine deaths occurred in southern and western Texas while Erin was a tropical cyclone, and seven more (six in Oklahoma and one in Missouri) occurred from the remnant low—most fatalities resulted from inland flooding and vehicles swept away by floodwaters. Damage included flooding of more than 400 homes and about 40 businesses in the Houston area, localized beach erosion in Galveston and Freeport, and wind and flood damage northwest of Oklahoma City; insured-loss estimates did not exceed the $25 million reporting threshold used by Property Claim Services.

Noteworthy aspects include the well-anticipated genesis of Erin several days in advance and generally reasonable track forecasts given the storm’s short life, while intensity forecasts were limited by the brief tropical-storm phase. Also unusual was the remnant low’s brief, radar-evident eye-like structure and strong winds over Oklahoma on 19 August; NHC judged that episode was too short-lived and driven by upper-level features to be classified as a tropical, subtropical, or extratropical cyclone.