(BIVN) – Residents and visitors on Hawaiʻi island are being asked to prepare for another round of heavy rain and possible flooding this week. 

The entire State of Hawaiʻi is under a Flood Watch. The National Weather Service says a low pressure system to the west will draw moisture northward as it strengthens during the next couple of days, bringing rain and thunderstorms to the islands.  

“We are again looking at the potential for flash flooding and thunderstorms with this weather system, including in areas that were previously hit the hardest,” said Mayor Kimo Alameda. “As we prepare for the possibility of more severe weather, we are regularly communicating with Merrie Monarch festival and craft fair organizers as well as the visitor industry to ensure everyone stays safe, aware and connected.” 

County officials say peak rainfall is forecast from Wednesday night through Friday. “Puna and Kaʻū districts could see the highest rainfall amounts with this storm system, with Kona also at increased risk starting Thursday,” a news release stated.

Southerly winds are also expected, with gusts of 30 to 40 mph forecast in lower elevations. Peak wind impacts are expected on Thursday and Friday.

Graphic courtesy the National Weather Service in Honolulu

“This storm has a lot of energy and moisture, so we’re urging everyone to prepare for the worst,” said Talmadge Magno, administrator of Hawai‘i County Civil Defense. “It’s one thing to get five or eight inches of rain over several days, but this storm also could drop that much in a matter of hours – it’s just not clear where or when.” 

County officials say sandbags can be requested by contacting the Department of Public Works at dpwhwy@hawaiicounty.gov or 808-961-8321. 

Hele-On bus and paratransit passengers should prepare for the potential of route modifications or cancellations due to the weather, the County says. 

The County provided this General Safety Information:

• If severe weather threatens, avoid unnecessary travel. If you must travel, use extra caution when on the roadway.
• Never try to cross moving water, on foot or in a vehicle: “Turn around, don’t drown.”
• Know the areas that are prone to flooding, particularly those near your home. Heavy rain uphill from your location can cause flooding, even if it’s not raining where you are.
• Monitor local forecasts from reliable sources for the latest information about the storm and its potential hazards. Have a battery- or crank-powered radio to receive information during a power outage. (Don’t forget the car radio.)
• If lightning threatens, the safest place to be is indoors. If you’re in a vehicle, stay in the vehicle.
• Have a “go bag” ready in case you must evacuate the area, especially if your home is in an area prone to flooding. It should include food, water, necessary medication, important documents, and other necessities for the members of your household (including pets) if you need to leave in a hurry.
• Check in with neighbors, especially those who may have mobility problems, to make sure they have a safe way to evacuate if flooding strikes.

The Hawaiʻi County Department of Water Supply is also urging customers to be drinking water prepared.

Water preparation tips include:

• Determine Household Water Needs. Each person should have a minimum of one gallon of water per day for at least 14 days, according to the Hawai‘i Emergency Management Agency (HI-EMA). Pets and livestock also require water.
• Store Water Safely. Use only clean, dedicated, food-grade containers. Wash containers thoroughly with dishwashing soap, sanitize using one teaspoon of mild liquid chlorine bleach per quart of water, and then rinse thoroughly. Fill containers from the tap, leaving as little air as possible. Store in a cool, dark area. Water that has not been commercially bottled should be replaced every six months, according to the Federal Emergency Management Agency (FEMA).
• Treat Drinking Water. During an emergency, it may be necessary for DWS to issue a Boil Water Notice due to water quality problems. Customers will be made aware of this via various communication channels. If this is necessary, instructions to treat water can be found on FEMA’s website.
• Restrict Water Use. During emergencies, restrict water use to essential uses only such as drinking, cooking, and personal hygiene. No lawn watering, car/boating washing, etc.