Tropical Storm Don 2011

Tropical Storm Don developed after being classified as an invest for nearly a week. The fourth tropical cyclone and fourth named storm of the 2011 Atlantic hurricane season, Don developed on July 27 from a persistent tropical wave in the southeastern Gulf of Mexico.

Meteorological history

The genesis of Tropical Storm Don was from a tropical wave first identified off the west coast of Africa in mid-July. Preceded by a surge of deep tropical moisture, it tracked westward over the open Atlantic for several days, with minimal convection confined to the monsoon trough. Throughout its journey, the wave became increasingly embedded within a broad area of cyclonic wind flow, enhancing the convection. The National Hurricane Center first mentioned the potential for gradual tropical cyclogenesis on July 21, when it was positioned about 750 mi (1200 km) to the east of the Windward Islands. As it neared the islands the next day, it briefly became better defined, although a spell of vertical wind shear and proximity to land impeded further development. Still in the vicinity of abundant moisture, the system generated largely scattered thunderstorms over much of the northeastern Caribbean, all the while deteriorating in organization.

Convection waxed and waned for several days during its passage through the Greater Antilles, and by July 25 significant redevelopment was not expected. The following morning, however, shower and thunderstorm activity reintensified south of western Cuba while the wave retraced to the west-northwest and slowed. It continued to gain in organization over the waters of the Yucatán Channel; radar data early on July 27 suggested a surface circulation was in the process of forming. In addition to surface wind estimates of 40 mph (65 km/h), a reconnaisance aircraft flight into the system confirmed the presence of a closed albeit elongated circulation center, prompting the NHC to initiate advisories on Tropical Storm Don at 2100 UTC that day. At the time, it was located about 120 mi (190 km) north of Cozumel, Mexico, steered along the southern periphery of a low- to mid-level ridge over the northern Gulf of Mexico.

Preparations

After the storm was named, officials in Texas began making preparations for Don. The University of Texas Medical Branch in Galveston issued a level one alert for Don, and city officials began preparing for a possible evacuation.

On July 27, Oil companies throughout the western Gulf of Mexico began removing non-essential personnel from their rigs and platforms in preparation for the storm. The next day, BP, Royal Dutch Shell, Anadarko and Apache announced the evacuations of some of the oil facilities in the area, while Exxon-Mobil began preparing the Baytown Refinery for a possible strike from the storm.

The state civil protection agency in Quintana Roo warned that the tropical wave from which Don formed was capable of dropping 80 to 150 mm (3.1 to 5.9 in) of rainfall over the state, while producing sustained winds of 35 to 45 km/h (22 to 28 mph) and gusts up to 65 km/h (40 mph). After Don was designated as a tropical storm, the Yucatán state government issued a green-level alert. The alert indicated that although the tropical storm was located close to the state, it was only considered to be slightly dangerous.

Late on July 27, the National Hurricane Center issued Tropical Storm Watches from Port Mansfield, Texas to San Luis Pass, Texas. Six hours later, the Tropical Storm Watch was extended southwards to the international border.

Impact

Several oil companies stopped oil production as a result of Don; by midday on July 28, 6.8% of oil production and 2.8% of natural gas production in the Gulf had been shut in ahead of the storm.

Current storm information

As of 4 p.m. CDT (2100 UTC) July 28, Tropical Storm Don is located within 30 nautical miles of 24.9°N 91.3°W, about 425 mi (690 km) east-southeast of Corpus Christi and about 395 mi (635 km) east of Brownsville. Maximum sustained winds are 40 knots (45 mph, 75 km/h), with stronger gusts. Minimum central pressure is 1005 mbar (hPa; 29.68 InHg), and the system is moving northwest at 14 kt (16 mph, 26 km/h).

Tropical storm force winds extend outward up to 85 miles (140 km) from the center of Don.

Don closes on Texas coast, will spread much-needed rain

BP, ExxonMobil, Anadarko, Apache and Royal Dutch Shell shut in output from offshore platforms

--U.S. government says 6.8% of Gulf oil production, 2.8% of natural gas shut-in

--Tropical Storm Don moving toward Texas coast

--Don isn't expected to gain hurricane strength, NHC said

--ExxonMobil begins storm preparations at Baytown, Texas, refinery, nation's largest

(Adds tropical storm warnings in 4th paragraph and updates storm location in 5th paragraph)

Don had maximum sustained winds of 50 mph (85 kph) with higher gusts at 5 a.m. ET, quickly spinning toward the west-northwest at 14 mph (22 kph).

The storm was about 290 miles (470 km) southeast of Corpus Christi and about 245 miles (395 km) east of Brownsville.

"Some strengthening is possible until landfall, with weakening likely by Saturday morning," the hurricane center said.

Tropical storm force winds extend outward up to 105 miles (170 km), but mainly to the north and east of the storm's center.

It's not often that news of a tropical storm is welcomed, but Don's expected heavy rainfall may prove to be a silver lining for Texas.

"Some parts of Texas are more than 15 inches below average (for rainfall). This storm will likely not be a drought-buster, but could at least put a dent in and around where the storm makes landfall," CNN meteorologist Dave Hennen said Thursday. If Don "does not intensify into a hurricane, this is likely a good thing."

Any rain would be a welcome relief for many Texas farmers, who are suffering from the third worst drought in recorded history, according to the U.S. Department of Agriculture.

Most farmers have adopted an "I'll believe it when I see it" attitude when it comes to predicted rain, Texas Agriculture Commissioner Todd Staples said.

He also noted that even with the drought, this rain might not be a good thing for cotton farmers in coastal regions.

"We needed the rain during the growing season and we're getting it during harvesting -- it's the complete reverse here," he said.

"Along the Gulf Coast they're harvesting cotton and it could add insult to injury because the rain lowers the quality and makes harvesting difficult," he said. "All of this results in higher prices to the consumer because our supplies will be more limited."

Despite the drawbacks for the cotton industry, Staples said there's no denying the state desperately needs the rain.

"Unfortunately, no part of Texas has escaped the damage of this drought," he said. "We welcome Tropical Storm Don as much as we're looking forward to Friday night football.

Corpus Christi, Texas, resident Aubrey Carter, 87, has been diligently waking up at 3 a.m. to water her grass during the designated water restrictions.

"We are looking forward to Don coming because the drought has been so severe and everybody needs rain," she told CNN.

MaryJane Crull, marketing director at the South Texas Botanical Gardens in Corpus Christi, told CNN, "We're excited about it if Don remains a low-key tropical storm. ... We can handle six to eight inches of rain without a problem."

Wetlands on the property need the rain, Crull said.

"This will put water back in them and this will make birds and wildlife on our property happy and make visitors happy as well."

Companies with personnel along the Texas coast were quickly preparing.

ExxonMobil began evacuating nonessential personnel from offshore facilities in the path of the storm Thursday, spokesman Patrick McGinn said. Gross production of approximately 8,000 barrels per day of liquids and 50 million cubic feet per day of natural gas was shut down.

The U.S. Coast Guard issued a warning Thursday afternoon, urging people to plan and prepare ahead of the storm. The statement cautions residents to stay clear of beaches, to take action early -- including securing boating equipment and hazardous materials -- and to evacuate as necessary.