Residents and visitors advised to prepare for possible flash flooding and thunderstorms

A NOAA satellite picture of the conditions over O‘ahu today.

HONOLULU— O‘ahu residents and visitors are advised to prepare for possible heavy rains and flash flooding that could begin to affect the island later this afternoon.

“The National Weather Service advised us this morning that an upper level low and trough west of the state will bring an increased chance of severe weather, heavy rain and possibly thunderstorms, which could begin affecting us as early as this afternoon and lasting through Wednesday,” said Hiro Toiya, director for the city’s Department of Emergency Management (DEM). “In addition we could see heavy rainfall in areas of O‘ahu not normally associated with flooding such as the ‘Ewa plains, Kapolei and the Leeward coast of O‘ahu. Flooding rains could result in evacuations, road closures and possible utility outages.”

O‘ahu residents need to consider the following flood and flash flood preparedness actions.

Flood and Flash Flood Preparedness:

When a flash flood WARNING is issued for your area, or the moment you realize that a flash flood is imminent, act quickly to save yourself and your family.

Get out of areas subject to flooding. This includes dips, low spots, washes, etc.

Avoid already flooded and high-velocity flow areas. Do not attempt to cross flowing streams.

If driving, be aware that the roadbed may not be intact under floodwaters. Turn around and go another way. Remember, turn around, don’t drown!

If your vehicle stalls, assess whether you should leave it immediately and seek higher ground. Rapidly rising water may engulf the vehicle and its occupants and sweep them away.

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

Do not camp or park your vehicle along streams and washes, particularly during threatening conditions.

If advised to evacuate, do so immediately.

Move to a safe area before access is cut off by floodwater.

Monitor NOAA Weather Radio, television, radio or official social media for emergency information.

Before the flood:

Consider securing sand bags and other flood protection items if your home or business is in a flood prone area or has experienced flooding in the past.

Bring in outdoor furniture and move important indoor items to the highest possible floor. This will help protect them from flood damage.

Keep gutters and drains free of debris.

Do not dispose of yard waste or trash into streams or estuaries. Keep them clear to alleviate flooding.

Review your homeowner’s policies to understand what may or may not be covered by your flood insurance.

During the flood:

Minimize vehicle travel or better yet, plan to stay at home until weather conditions improve and any watches or warnings are cancelled.

Avoid areas subject to sudden flooding.

If you come upon a flowing stream where water is above your ankles, STOP! Turn around and go another way. Remember: turn around, don’t drown!

Do not open sewer or utility covers to drain floodwaters.

Children should NEVER play around high water, storm drains or viaducts.

After the flood:

Stay Informed: Stay tuned to your local news for updated information on road conditions. Ensure water is safe to drink, or to use for cooking or cleaning after a flood. Authorities may ask you to boil water for a certain period of time after a flood. Utility companies often have apps to update you on getting service back. Carbon monoxide poisoning is one of the leading causes of death after storms when areas are dealing with power outages. Never use a portable generator inside your home or garage.

Avoid Flood Waters: Standing water hides many dangers including toxins and chemicals. There may be sharp objects under the water or the road could have collapsed. If it is likely your home will flood, don't wait for evacuation order, get out! Talk to friends and family about emergency visits. If you have pets, take them with you or get them somewhere safe.

Avoid Disaster Areas: Do not visit disaster areas. Your presence may hamper rescue and other emergency operations.

Heed Road Closed Warnings and Cautionary Signs: Road closure and other cautionary signs are put in place for your safety. Pay attention to them!

Wait for the All Clear: Do not enter a flood-damaged home or building until you're given the “All Clear” by authorities. If you enter a flood-damaged building, be extremely careful. Water can cause floods to collapse, ceiling to fall, etc. Make sure the electrical system has been turned off. Have the power company or a qualified electrician fix wires. Contact your insurance agent to discuss property damage. If you have a generator, follow proper safety procedures.

If you experience a flood related emergency call 9-1-1 immediately.

Emergency Information

In addition to being prepared residents should maintain a high level of awareness anytime periods of severe weather are expected. DEM will issue Emergency Public Information over TV, radio and official social media. In addition residents can receive emergency information via:

NOAA Weather Radio - NOAA Weather Alert Radios can notify you 24-hours a day to hazards in our area including severe weather, hurricanes and tropical storms and tsunami events. Many of these units can activate other warning devices such as a strobe light to provide a visual warning. These radios are available from many Oahu electronics and department stores.

HNL.info - DEM highly recommends signing up to receive free emergency email and text messages and push alerts sent directly to your cell phone from HNL.info. Go to https://hnl.info/alerts/login to set up your account or download the free app from the App Store or Google Play.

Social Media - DEM will also issue information updates via:

DEM Twitter www.twitter.com/Oahu_DEM

DEM Facebook www.facebook.com/OahuDEM.

NOTE: DEM Twitter and Facbook pages should not be used to request emergency assistance.

It’s also a good idea to follow Mayor Kirk Caldwell’s social media sites:

Twitter: @MayorKirkHNL

Facebook: facebook.com/MayorKirk

YouTube: youtube.com/MayorKirkHNL

Instagram: instagram.com/mayorkirkhnl

—PAU—