Tropical Storm Isaac continued to lash New Orleans with heavy rain today despite being downgraded, as residents in cars and homes were stranded exactly seven years after Hurricane Katrina devastated the city.

Hurricane Isaac has swept into New Orleans exactly seven years after the devastating Katrina, stranding people in cars and homes as it pushed flood waters over defences in one rural area.

More than 500,000 people have lost power as Hurricane Isaac moves through south-east Louisiana, bringing torrential rain and flooding.

Hurricane Isaac has lashed the Louisiana coast and is heading for a shuttered New Orleans, sending floodwaters surging and unleashing fierce winds.

Hurricane Isaac made landfall in south-east Louisiana today, with winds of nearly 80mph.

Tropical storm Isaac strengthened into a hurricane just off the US Gulf Coast as it churned toward landfall in the New Orleans area seven years to the day after the city was devastated by Hurricane Katrina.

Isaac turned into a full-blown category 1 hurricane today as it rolled over the Gulf of Mexico toward Louisiana, where residents in four states left boarded-up homes and New Orleans waited nervously behind flood-defence levees strengthened after the devastating Katrina struck exactly seven years ago.

Republicans have moved into the ritual of formally nominating Mitt Romney as their candidate to unseat president Barack Obama, anxiously watching a storm threatening to hit New Orleans just as the first political speeches begin.

Tropical storm Isaac was on the verge of becoming a full-blown hurricane as it rolled over the Gulf of Mexico toward Louisiana.

The centre of Tropical Storm Isaac’s projected path is heading directly for New Orleans and could make landfall as early as tonight, nearly seven years to the day after Hurricane Katrina devastated the city.

Tropical Storm Isaac churned across the Gulf of Mexico yesterday, disrupting US offshore energy production and threatening to hit Louisiana on the anniversary of the devastating Hurricane Katrina in 2005.

Tropical Storm Isaac gained fresh muscle today as it neared the Florida Keys, threatening to be at or near hurricane strength approaching the island chain.

A potential hurricane is posing a threat to next week’s Republican National Convention in Florida, which culminates in the nomination of Mitt Romney for presidential candidate.