*

Hurricane warnings issued across much of Texas coast

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Storm previously caused 11 deaths and destruction in the

Caribbean

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Oil companies adjust operations; Shell evacuates workers

from

platforms

(Adds update on hurricane from latest NHC advisory)

By Tyler Clifford

July 7 (Reuters) - Hurricane Beryl strengthened as it

neared the Texas coast on Sunday, the U.S. National Hurricane

Center (NHC) said, forcing the closure of major oil ports,

flight cancellations and a warning it would be a deadly storm

for communities hit.

Beryl, the earliest category 5 hurricane on record, last

week swept through Jamaica, Grenada, St. Vincent and the

Grenadines, toppling buildings and power lines and killing at

least 11 people.

The storm weakened after its deadly trail of destruction

across the Caribbean, but strengthened into a category 1

hurricane as it crossed the warm waters of the Gulf of Mexico.

By the time it reaches landfall near Houston on Monday it

could be a category 2 storm.

"Additional strengthening is expected before landfall on the

Texas coast," the NHC said in its latest advisory.

Acting Governor Patrick on Sunday declared 120 counties to

be disaster areas ahead of the storm and warned Beryl "will be a

deadly storm for people who are directly in that path."

School systems - including the state's largest in Houston -

said they would be closed as the storm approached. Airlines

canceled hundreds of flights, and officials ordered a smattering

of evacuations in beach towns.

Closures of major oil-shipping ports around Corpus Christi,

Galveston and Houston ahead of the storm could disrupt crude oil

exports, shipments of crude to refineries, and motor fuel from

the plants.

OIL REFINERIES

Most of the northern Gulf's offshore oil and gas production

is east of Beryl's forecast track.

Some oil producers, including Shell and Chevron ( CVX )

, had evacuated personnel from their Gulf of Mexico

offshore production platforms ahead of the storm.

Citgo Petroleum Corp said it plans to keep the Corpus

Christi refinery running at minimum production as the storm

moves up the coast.

Gibson Energy ( GBNXF ), which operates a large oil terminal

in Corpus Christi, said operations were continuing, but it would

take further steps depending on the forecast.