Americans have barely started recovering from the devastation left in the wake of Hurricane Harvey.
But Hurricane Irma could be even worse.
What started typical hurricane near Cape Verde islands has grown into a category five cyclone, as 5.6 million Floridians - or 25 per cent of the state's population - have been asked to evacuate.
Here is why Hurricane Irma looks so dangerous.
1. It is over 400 miles across.
That's larger than Ohio.
2. It is currently a 5.3 on the Cyclone Damage Potential Index.
Hurricane Harvey was 5.2 and Katrina was 4.9.
3. Even seismometers are registering it.
They're the things designed to measure earthquakes.
4. It is expected to register as Category 4 or more for five days in a row.
Which would be the fourth time since 1966.
5. Winds could reach 215mph
While airplane measurements suggest it can sustain winds at 155mph.
This is at a "life-threatening" strength according to the National Hurricane Centre.
6. Waves could reach up to 23 feet.
7. It could cost as much as $125 billion in damages.
And if it stays at Category 5 when it hits Miami, Credit Suisse estimates the cost could be double that.
It has already left other areas devastated.
Irma is expected to reach Florida on Sunday.