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(Adds tornado warnings, flight cancellations and pipelineoutage, paragraphs 5, 7 and 10)
By Kristen Hays
HOUSTON, June 16 (Reuters) - Tropical Storm Bill punched theTexas coast with heavy rains and strong winds on Tuesday, theNational Weather Service said, just three weeks after floodskilled about 30 people in the state.
The second named tropical storm of the 2015 Atlantichurricane season made landfall near Matagorda, a sportfishingtown near the South Texas Nuclear Generating Station in BayCity, a coastal nuclear power plant.
Spokesman Buddy Eller said the plant had prepared for thestorm and operations were normal with full staffing.
Companies said output from oil platforms in the Gulf ofMexico, which pumps about a fifth of all domestic crude, wasunaffected.
But BP Plc shut its Mad Dog and Atlantis fields earlyon Tuesday after a pipeline outage that was expected to be fixedsoon, a source said. It was unclear if the storm caused theoutage.
Vessel traffic was halted in the Houston Ship Channel, thebiggest U.S. petrochemical port, and ports in Galveston andTexas City, officials said.
Forecasters cautioned that tornadoes were possible acrossmuch of Texas. Flash flood watches were issued for six states.The watch area included Houston and central Texas, where floodsover Memorial Day weekend last month swept over thousands ofvehicles and damaged homes.
The storm was projected to churn through central Texastoward Austin and Dallas, though tropical storm-force winds near60 miles per hour (96 km) extended 150 miles (241 km) from thecenter.
Heavy rain had already drenched parts of Texas over theweekend, pushing high rivers closer to overflowing their banks.The National Hurricane Center said the storm was expected toweaken into a tropical depression overnight, but it could bringup to 8 inches (20 cm) of rain to eastern Texas and Oklahoma andup to 4 inches (10 cm) to Arkansas and southern Missouri.
Around Houston, the fourth-largest U.S. city, schooldistricts suspended summer classes, and 209 flights werecancelled at the two airports serving the city, according ottracking service FlightAware.com.
Voluntary evacuations were called for some low-lying areassouth of Houston.
Flooding could snarl work in Texas oilfields, but producersincluding EOG Resources and ConocoPhillips saidoperations were normal.
More than 45 percent of U.S. refining capacity and half ofnatural gas processing capacity sits along the U.S. Gulf Coast.
Onshore, LyondellBasell deployed sandbags at itsrefining and chemical facilities. Refiner Phillips 66 said operations had no weather impacts. (Additional reporting by Erwin Seba, Anna Driver and KristenHays; Writing by Terry Wade; Editing by Larry King and TomBrown)
