Mayor Muriel e. Bowser signed the effective immediately state of emergency, along with several other DC officials, on Tuesday and held a news conference to share how authorities are preparing.

At this point DC is mainly preparing for periods of heavy rain, starting Thursday night and continuing into Friday, say officials.

Roughly one million people have been ordered to evacuate from South Carolina’s entire coastline, while more than 245,000 Virginians were issued a mandatory evacuation in preparation for “potential catastrophic flooding”, said Governor Ralph Northam.

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Florence is now a Category 4 hurricane, packing winds of up to 140mph (224kph). It is expected to make landfall in the US, Thursday as an “extremely dangerous” hurricane according to the National Hurricane Center.

The agency has warned of “life-threatening” storm surges along the south-eastern seaboard and freshwater flooding due to a “prolonged and exceptionally heavy rainfall event.” Florence could be the worst hurricane to hit the Carolinas in over 60 years since category 4 hurricane ‘Hazel’ struck in 1954.