Nor'easter and coastal flood safety
Nor'easters can push seawater onto coastal roads and homes. When a Coastal Flood Warning is issued, move to higher ground, never drive or walk through floodwater, and follow evacuation orders. Prepare early by knowing your flood risk and the tide gauge level that floods your street.
Information may be delayed or incomplete. Always verify with official sources and follow local officials.
What is a nor'easter?
“A Nor’easter is a storm along the East Coast of North America, so called because the winds over the coastal area are typically from the northeast. These storms may occur at any time of year but are most frequent and most violent between September and April.”National Weather Service, What is a Nor'easter?
The National Weather Service says nor'easters nearly always bring heavy rain or snow, gale-force winds and rough seas, and sometimes coastal flooding. The I-95 corridor from Washington, D.C., to Boston is hit especially often.
What the coastal flood alerts mean
NWS Newport/Morehead City explains the alerts this way (NWS Coastal Flood Products):
- Coastal Flood Advisory: minor or nuisance coastal flooding is occurring or imminent, usually water 1 to 2 feet above ground there.
- Coastal Flood Watch: moderate to major coastal flooding is possible.
- Coastal Flood Warning: moderate to major coastal flooding is occurring or imminent, a serious threat to life and property, usually water 3 feet or more above ground there.
- High Surf Advisory: large breaking waves causing minor beach erosion or ocean overwash.
The exact water levels behind each alert vary from place to place. NWS Baltimore/Washington says to plan on about 12 to 24 hours of notice for moderate or higher tidal flooding, and notes that NOAA Weather Radio sounds its alert tone for Coastal Flood Warnings but not for Advisories (NWS: Tidal flood). Get alerts more than one way.
Before the storm
- Know your risk. Look up your address on FEMA's Flood Map Service Center. Ready.gov notes flooding doesn't follow lines on a map.
- Find your tide gauge. NWS Baltimore/Washington says to learn the water level at your nearest gauge that floods your street, then plan what you'll do at each level. Gauges are on NOAA Tides & Currents.
- Protect your property. Secure loose objects, board up windows close to the ground and know your evacuation routes (NWS Melbourne). Move valuables to higher levels, clear drains and gutters, and consider check valves and a sump pump with a battery (Ready.gov).
- Pack your papers. Keep documents in a waterproof container, with password-protected digital copies (Ready.gov). Our emergency kit checklist has the rest.
- Check your insurance now. Ready.gov says homeowners policies do not cover flooding, and a new flood policy typically takes up to 30 days to start. See Flood insurance waiting period.
When the water rises
“If coastal flooding is observed, act quickly. Move inland to escape flood waters. Do not stay anywhere near the coast when water begins rising.”NWS Melbourne, Coastal Flood Safety Rules
- Evacuate right away if officials tell you to. Officials, not this site, decide who must leave.
- Be extra careful at night, when coastal flooding is harder to see (NWS Melbourne).
- If you're stranded, stay inside and go to the highest floor with water, food, a flashlight and a portable radio (NWS Melbourne). Ready.gov says not to climb into a closed attic, where rising water can trap you.
- Don't fish or watch the waves from piers, jetties or sea walls. Large waves can suddenly sweep across areas that were dry (NWS Melbourne).
“A mere 6 inches of fast-moving flood water can knock over an adult. It takes just 12 inches of rushing water to carry away most cars and just 2 feet of rushing water can carry away SUVs and trucks.”National Weather Service, Turn Around Don't Drown
Never drive around barriers blocking a flooded road. The National Weather Service says the road may have collapsed under the water.
After the water goes down
Go home only when officials say it's safe. Stay out of standing water, which can hide debris or be charged by downed lines. Photograph everything before you clean (photo checklist), then start drying within 24 to 48 hours (water damage and mold). If the storm knocked out power, see Power outages.
Common questions
What is a nor'easter?
The National Weather Service says a nor'easter is a storm along the East Coast, named for winds over the coast that typically blow from the northeast. They can happen any time of year but are most frequent and most violent between September and April.
What is the difference between a coastal flood advisory, watch and warning?
An advisory means minor coastal flooding is occurring or imminent. A watch means moderate to major coastal flooding is possible. A warning means moderate to major coastal flooding is occurring or imminent, a serious threat to life and property (NWS).
Is it safe to drive through a flooded coastal road?
No. The National Weather Service says 12 inches of rushing water can carry away most cars and 2 feet can carry away SUVs and trucks. Turn around and find another route.
Does homeowners insurance cover coastal flooding?
Usually not. Ready.gov says homeowners policies do not cover flooding, and a new flood insurance policy typically takes up to 30 days to go into effect.
Live coastal flood alerts for your area: pick your state on the States page, or see Flooding and Storms to watch.