Tropical Storm Emma (2018)

**Tropical Storm Emma** was a was a near-hurricane strength tropical cyclone that caused flooding throughout Texas. The fifth named storm of the 2018 Atlantic hurricane season, it developed from a tropical wave that entered the Gulf of Mexico on July 13. Organization quickly ensued, and by noon on the following day, the system had intensified enough to be classified as Tropical Storm Emma. Moving on a steady northwesterly track, Emma reached its peak strength at just under hurricane status when it reached the Texas coastline on July 15, making landfall near Port O'Connor, Texas. The storm quickly weakened once inland, completely dissipating by July 17.

The storm caused moderate rainfall in inland areas that largely proved beneficial; damage totaled $2.58 million (2018 USD); three indirect fatalities occurred as a result of a traffic accident.

## **Meteorological history**

A tropical wave emerged into the Atlantic Ocean from the west coast of Africa on July 2. The system moved westward, and while located near the northwestern Bahamas on July 11, a substantial increase in convection resulted in a upper-level low building downwards to the middle levels of the troposphere, coinciding with the development of an upper level anticyclone.

A closed low-level circulation nearly developed on July 12 to the east of Key Largo, Florida, but it weakened due to the deep convection remaining to the north over the mid-level center. The mid-level storm continued westward and moved across Florida. After crossing the state, satellite imagery and data from Hurricane Hunters indicated a poorly-defined circulation center, thus warranting the system's upgrade to Tropical Depression Five while situated 150 mi (241 km) west-northwest of Naples, Florida.

With well-established outflow and low levels of wind shear, the depression strengthened as the circulation became better defined. On July 14, another Hurricane Hunters flight found a closed center and winds of 40 mph (65 km/h). In response, the JMC initiated advisories on Tropical Storm Emma later that day, A ridge over the south-central United States steered the storm in a generally northwestern course throughout its life, and the storm's structure gradually coalesced as it traversed the Gulf of Mexico. By July 15, convection organized into bands, and as its winds approached hurricane strength, an eye developed within the storm. Thunderstorm activity increased during the morning of July 16 as they continued to wrap around the center of the storm, but the strength of these storms was noted to be rather meager.

At 08:00 UTC on July 16, Emma made landfall landfall 35 mi (56 km) northeast of Port O'Connor, Texas with maximum sustained winds of 70 mph (110 km/h) and a minimum barometric pressure of 986 mbar (hPa; 29.12 inHg); this was the cyclone's peak intensity. After moving ashore, Emma quickly weakened to a tropical depression and moved westward into Texas. The system dissipated around 06:00 UTC on July 17.

## **Preparations and impact**

### **Texas**

As the storm was approaching, the Jarrell Meteorological Center (JMC) issued flash flood watches from Corpus Christi to Sabine Pass, Texas. Rainfall from the storm peaked at 9.27 inches (235 mm) in the town of Matagorda. A police officer in the city noted that almost every street was flooded. Due to rainfall from the storm, an automobile accident in Freeport resulted in three fatalities. The heavy rains resulted in considerable flash flooding in eastern Texas, causing residents to evacuate their homes. Flood waters also forced the shutdown of Highway 35. In Calhoun County, two people were injured in automobile accidents.

While the storm was located in the western Gulf of Mexico on July 15, the JMC issued a Hurricane Watch and Tropical Storm Warning from Port O'Connor to Freeport, Texas. Late that same day, when strengthening was underway, a Hurricane Warning was either issued or recommended for the aforementioned areas, though winds in the storm never reached hurricane strength.

Emma also produced tides 6 to 8 ft (1.8 to 2.4 m) above normal, causing minor beach erosion along the Texas coast. Emma spawned several tornadoes in the state of Texas, one of which caused an estimated $15,000 (2018 USD) in damage at Galveston Island. After the storm, the American Red Cross opened storm shelters for residents forced out of their homes because of the flooding. Due to adverse conditions, "hundreds" were left without electricity in Port O'Connor, Matagorda, Sargent, and Freeport. In addition, President of the United States Donald Trump declared Matagorda and Brazoria counties as disaster areas, allowing them to receive federal aid. Overall, Emma caused three fatalities and $2.5 million (2018 USD) in damage within the state of Texas.