One of the biggest concerns with Hurricane Sally is excessive water.
- Short term — the main concern is storm surge and heavy rainfall, both leading to a high risk of flash flooding.
- Long term — the main concern is river flooding.
The flooding is more of a delayed concern with rivers because the runoff water from streets and homes first flows into drainage or smaller creeks and streams.
Then all of that water eventually collides into the bigger rivers, and those rivers swell. In Sally's case, they swell to dangerous levels.
Right now, there are 13 river gauges expected to reach Major Flood Stage across three different states.
In Barrineau Park, Florida, the Perdido River is of particular concern as it is currently forecast to reach a height of 27.1 feet, breaking the all-time record of 26.3 feet.
Another location to watch is the Styx River in Elsanor, Alabama, which is currently forecast to get to a height of 27.2 feet, within one foot of the all-time record of 28.6 feet.
Depending on how much rain actually falls along and near this river could cause this forecast to change.