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River flooding along major streams is generally slower to develop than flash flooding. But there are exceptions, especially near headwater areas of smaller rivers where the time lag between the runoff from heavy rain and the onset of flooding can be very short. On the other hand, it may take several days or maybe a week for a flood crest to pass downstream points on major rivers. The National Weather Services issues River Flood Warnings when rivers are expected to rise above flood stage. Crest forecasts for specific points downstream are given, along with known flood stages for each point. It is important that everyone living near a river know how to react to the various flood crest forecasts that may be issued. While there is more warning lead time than with flash floods in most cases, advance planning and preparation are essential to safeguard life and property from the dangers of mainstream flooding.

 

FLASH FLOODING

Flash flooding can occur almost anywhere in Mississippi. Flash flooding does not necessary occur in the classic “wall-of-water” concept. Simply stated, a flash flood is too much water in too short a time. Whether it occurs from excessive rainfall or a dam failure, flooding develops very quickly. Rapidly rising water in a low area or near a drainage ditch or small stream may not be as spectacular as a rushing wall of water down a canyon. But it can be just as deadly. In Mississippi, it is not uncommon for excessively dry conditions to change to flash flooding within a few hours. Many deaths occur when people drive into areas where water covers the road. It is extremely hard to judge how much water may be on the roadway. Avoid taking any chances – find alternative routes, or wait for the water to go down.  Certain geographical characteristics make some areas more flood-prone than other areas. Typically, low-lying areas near lakes or streams- or downstream from a dam- are more at risk of flooding. Even some higher, more mountainous areas may be at risk from flood- particularly flash floods. To find you live in a flood area start by checking FEMA’s flood map database. (This is usually done when you buy a house and take out a mortgage for the purchase of the house. If you buy a house or live in a flood-prone area you may have to buy flood insurance.) The best way to avoid being the victim of a flood is not to build in flood-prone areas- and to not remain in such areas during a flood watch.

  • Floods and flash floods happen in all 50 states.
  • Everyone lives in a flood zone.
  • Homeowners insurance doesn't cover flood damage.
  • Just an inch of water can cause costly damage to your property.
  • A car can easily be carried away by just two feet of floodwater.
  • Hurricanes, winter storms and snowmelt are common (but often overlooked) causes of flooding.
  • Every year, flooding causes more than $2 billion of property damage in the U.S.

Use this checklist to prepare for flood-related emergencies:

1. Know what to expect.

• Know your area’s flood risk - if unsure, call your local Red Cross chapter.

• If it has been raining hard for several hours, or steadily raining for several days, be alert to the possibility of a flood.

• Listen to local radio or TV stations for flood information.

• Floods take several hours or days to develop.

• Flash floods can take only a few minutes or a few hours to develop.

2. Prepare a family disaster plan.

• Check your homeowner’s or renter’s insurance policy to see if it covers flooding. If not, find out how to get flood insurance.

• Keep insurance policies, documents and other valuables in a safe deposit box.

• Assemble a Disaster Supplies Kit.

3. When a flood or flash flood WATCH is issued:

• Move your furniture and valuables to higher floors.

• Fill your car’s tank, in case an evacuation notice is issued.

• Be alert to signs of flash flooding and be ready to evacuate on a moment’s notice.

4. When a flood or flash flood WARNING is issued:

• Listen to NOAA weather radio, local radio and TV stations for information and advice. If told to evacuate, do so as soon as possible.

• Or if you think it has already started, evacuate immediately. You may have only seconds to escape. Act quickly!

• Move to higher ground away from rivers, streams, creeks and storm drains. Do not drive around barricades - they are there for your safety.

• If your car stalls in rapidly rising waters, abandon it immediately and climb to higher ground.

WHEN FLOODING OCCURS

Follow these tips to survive flooding or flash flooding:

• Store drinking water in clean bathtubs and containers.

• Move essential items to safe ground (second story or on tops of tables).

• Fill fuel tanks to keep them from floating away.

• Move to a safe area prior to being cut off by flood waters. Get to higher ground immediately, and stay away from low lying areas.

• Get out of areas that are subject to flooding.

• Do not drive through flooded areas. Driving into areas where water covers the road to an unknown depth can be dangerous since even shallow water can wash a car off the road.

• Be especially cautious driving at night when it is harder to recognize flood dangers.

• Do not camp or park your vehicle along streams or washes.