Flash flood watch issued for all islands through Sunday afternoon

The Honolulu Star-Advertiser
·12 min read

Mar. 14—For updates on Sunday's weather, .------UPDATE : 6 :35 a.m.

The statewide flash flood watch has been extended through this afternoon.

The National Weather Service said that "an upper level disturbance over the region and saturated ground conditions will maintain the potential for flash flooding through this afternoon."

Forecasters say significant flooding may occur due to the overflow of streams and drainages. They also warned of possible road closures and landslide.

An earlier flood advisory for Kauai has been canceled.

Sunday 1 a.m.

Kauai's flood advisory has been extended until 4 a.m.

Radar and satellite indicated numerous showers moving over Kauai from the northeast, with additional showers extending well upstream. Showers are moving quickly, but their repeated development over the slopes are expected to continue.

Saturday, 9 :40 p.m.

Kauai's flood advisory has been extended to 1 a.m. Sunday.

The National Weather Service said radar and satellite indicated numerous showers moving over Kauai from the northeast, with additional showers extending well upstream.

Showers are moving quickly, but their repeated development over the slopes is expected to continue. Runoff will be high since the ground is already saturated.

7 :25 p.m.

The National Weather Service has extended the flood advisory for Kauai County until 10 p.m.

"At 6 :44 p.m., radar and satellite indicated numerous showers continue to move over Kauai from the northeast, with additional showers extending well upstream, " the advisory said. "Showers are moving quickly, but will remain anchored near and over the mountain slopes. The ground is saturated, so runoff will be high."

The flood advisory includes the entire island but especially north and east Kauai, forecasters said.

A flash flood watch was extended for all islands until 6 a.m. Sunday.

6 :30 p.m.

Maui County's Department of Public Works reported two washouts this afternoon on Piilani Highway on the south flank of Haleakala.

One was at Pahihi Gulch, where there is a dirt road at the gulch crossing, but no bridge.

The other is at Nuu Gulch, where there is a culvert and a concrete ford. Portions of the concrete and asphalt pavements have washed away. No information was available on the condition of the culvert, the mayor's office said.

The washouts occurred shortly before 4 p.m. today.

UPDATE : 5 :15 p.m.

The flood advisory for Hawaii island has been canceled, but the advisory for Kauai is still in effect until 7 p.m.

"At 3 :25 p.m., radar and satellite indicated numerous showers moving over Kauai from the northeast, with additional showers extending well upstream, " the National Weather Service advisory for Kauai said. "Showers are moving quickly, but their repeated development over the slopes is expected to continue. The ground is saturated, so runoff will be high."

The flood advisory includes the entire island but especially north and east Kauai, forecasters said.

A flash flood watch was extended for all islands until 6 a.m. Sunday.

4 :40 p.m.

Hawaii County had the following road closures today :—In Hilo, State Highways closed the Hilo inbound lanes of the Kanoelehua and Kahaopea intersection. The inbound lanes will remain closed for up to 12 hours to repair traffic lights damaged earlier, Hawaii County Civil Defense Agency said in a 2 p.m. message.—Police reopened Highway 11 in Kau at 1 :30 p.m. to all traffic after a nearly 3-hour closure.—Due to flooding the highway had been closed from about 9 :10 a.m. near the 60-mile marker in Honuapo.

4 :03 p.m.

A flash flood watch has been issued for all islands until 6 a.m. Sunday.

A flash flood watch is currently in effect for Oahu, Kauai, Maui, Lanai, Molokai, Niihau and Kahoolawe through late tonight. A watch means that conditions are favorable for flash flooding, which is life-threatening.

"A front over the western half of the state, and fast-moving heavy showers over the eastern half of the state will maintain the potential for flash flooding through tonight, " according to a statement from the Hawaii Department of Emergency Management. "Significant flooding may occur due to the overflow of streams and drainages. Roads in several areas may be closed, along with property damage in urban or low-lying spots due to runoff. Landslides may also occur in areas with steep terrain."

The watch urged people to be prepared to take action if a flash flood warning is issued. "If you experience heavy rain or rising waters, head to higher ground immediately."

3 :30 p.m.

A flash flood watch remains in effect for all islands until 6 p.m.

The County of Maui Department of Parks and Recreation said in a news release the following areas on Maui have been closed as a result of the weather conditions :—Kanaha Beach Park and Baldwin Beach Park are closed due to flooding.—Halawa Park on Molokai is closed after a landslide that damaged a waterline.—Intermittent closures may occur at all county pools.—"Minimal to light water flowing " on sections of Kamehameha V Highway on Molokai at mileposts 6.5, 10.4, 12.5 and 16.—In South Maui, Kanakanui Road and Liloa Drive has been closed due to flooding ; Polo Beach-White Rock has been closed as a result of muddy conditions on the road ; Makena Road near Big Beach has been flooded, but considered passable.—Power problems affect traffic signs at Hana-Haleakala Highway intersection and Maui Veterans Highway at Hookele Street and Hansen Road.—Piilani Highway between mile markers 29-31 is closed as Maui County crews work to clear debris and clean up roadway.—A downed tree was blocking the area of 705 Kauhikoa Road in Haiku.—The road has been closed from Lelekea Stream to Upper Kanaio Road.

2 :40 p.m.

The flash flood warning for Maui County has expired, but a flash flood watch remains in effect.

"Heavy rain has eased, and water levels in streams and rivers are gradually subsiding, therefore the flash flood warning is allowed to expire, " according to a statement issued 2 :25 p.m.

2 p.m.

A flash flood warning remains in effect until 2 :30 p.m. for Maui County due to heavy rain, according to the National Weather Service.

"At 1 :29 p.m., radar indicated that rainfall had eased, but water levels in streams and rivers remain elevated due to earlier heavy rains. Although water levels are gradually diminishing, they remain high in the Kaupakalua Reservoir, " according to the warning issued 1 :29 p.m.

Forecasters warned of flooding in drainages, streams, rivers, roads, properties and low-lying areas. They also warned of potential rock and mudslides in steep terrain areas.

The warning may be extended if flooding persists.

1 :18 p.m.

A flood advisory has been extended for Hawaii County until 4 :30 p.m.

"At 1 :15 p.m., radar indicated spotty moderate to heavy showers across the entire Big Island, with showers moving toward the northeast at 10 to 15 mph. Additional showers will move onshore along the Kona coast, while other showers will develop along the windward slopes through the afternoon, " the advisory issued at 1 :15 p.m. said.

Forecasters are warning people to stay away from streams, drainage ditches and low-lying areas prone to flooding. The advisory also said rainfall and runoff will cause hazardous driving conditions as a result of ponding and reduced visibility.

A flash flood watch is also in effect.

Both lanes on Highway 11 near mile marker 60 are now open Honuapo in Kau, according to Hawaii County Police Department in a news release.

12 :10 p.m.

The National Weather Service has extended the flash flood warning for Maui until 2 :30 p.m.

"At 11 :16 a.m., radar indicated that rainfall was gradually easing, but runoff remains high and water levels in streams and rivers remains elevated. Additionally, water levels remain dangerously high in the Kaupakalua Reservoir, " the warning issued late this morning said.

Forecasters warn of possible flooding in drainages, streams, rivers, roads, properties and other low-lying areas, and landslides in steep terrain.

The weather service said emergency authorities on Maui report some homes in Kahului were getting flooded early this morning due to heavy rain overwhelming storm drains.

The Big Island is under a flood advisory until 1 :30 p.m.

"At 12 :03 p.m., radar indicated spotty moderate to heavy showers across the entire Big Island, with showers moving toward the northeast at 10 to 15 mph, " the advisory said. "Additional showers lie offshore the Kona coast, and will continue to periodically move ashore, bringing brief periods of heavy rain and low visibility."

The advisory now covers the entire Big Island, but especially the Kona and leeward Kohala Districts, forecasters said.

The entire state is under a flash flood watch until 6 p.m.

10 :30 a.m.

A flood advisory for Hawaii island is in effect until 1 :30 p.m.—Hawaii Department of Transportation reports that flooding has closed Highway 11 at mile marker 60 near Honuapo in Kau. There are no alternate routes, so motorists are advised to drive with caution and look out for run-off, ponding and debris on the roadways, DOT said in a tweet.

The flash flood warning for Kahului, Kihei and Wailuku on Maui continues until 11 :30 a.m.—Hawaii Department of Transportation reports a downed tree on Hana Highway at Maliko Gulch has blocked lanes.

9 :32 a.m.

A flash flood advisory for north and south Kohala, as well as north and south Kona districts on Hawaii island, continue through this afternoon.

Heavy rain, lightning and winds of up to 40 mph are forecast to occur throughout the day, according to Hawaii County Civil Defense Agency.

A flash flood advisory means localized flooding is happening or may occur. As a result, all residents in flood-prone areas are asked to remain alert for possible flooding. The agency warns that heavy rainfall and ponding will cause hazardous conditions. Highway 11 is closed at the 60-mile marker in Kau and more road closures may happen without notice.

"Do not attempt to cross flowing or rising water in your vehicle or on foot ; turn around, don't drown. If lightning threatens your area, the safest place to be is indoors, " according to the advisory.

8 :41 a.m.

The flash flood warning for Kauai has expired at 8 :45 a.m. A flash flood warning has been extended for Maui until 11 :30 a.m. Areas affected include Kahului, Kihei and Wailuku.

7 :45 a.m.

The flash flood warning for Molokai has been canceled. Warnings for Kauai and Maui continue, and the entire state remains under a flash flood watch until 6 p.m.

PREVIOUS COVERAGE The heavy rains that have plagued the Hawaiian islands all week continue today with three islands under flash flood warnings this morning and the entire state under a flash flood watch through 6 p.m.

Kauai, Molokai and Maui were all under flash flood warnings issued by the National Weather Service this morning.

Forecasters said the wet weather will continue "as a cold front moving through stalls over the eastern end of the state this weekend. Heavy showers and a few storms along and ahead of the front combined with saturated grounds will keep the threat for flash flooding in place."

They expect gusty north to northeast winds will focus clouds and showers over windward and mauka areas for Kauai and Oahu through the first half of next week as low pressure moves west across the state.

The warning for Kauai is until 8 :45 a.m.

"At 6 :22 a.m. radar indicated persistent heavy showers developing over already saturated ground, leading to rapid rises in water levels in streams and rivers, especially along the north and east side of the island, " the weather service said. "Rainfall over the mountains is expected to continue."

The warning covers the entire island but the weather service said the north and east sides are especially vulnerable to flooding.

Maui and Molokai are also under flash flood warnings.

The Maui warning is effective until 8 :30 a.m. and covers the entire island.

"At 5 :14 a.m., radar indicated heavy rain continuing over Maui. The heaviest rainfall is now over the southeast slopes of Haleakala, as well as a new band of showers moving into West Maui, the warning said. "Rain was falling at a rate of 1 to 2 inches per hour."

The weather service reported that streams on the island were running high, especially Oheo Gulch, and that Maui Civil Defense reported several landslides including Highway 30 on the Wailuku side of the tunnel and Kula Highway near mile marker 18.

The Molokai warning is effective until 8 :15 a.m.

"At 5 :22 a.m., the Kawela Gulch reported a rapid rise in water level and continues to increase, " the weather service said. "Flooding is likely along Kamehameha Highway near the Kamalo Dip and other nearby low water crossings."

Locations that will experience flash flooding include Kamalo, Kalaupapa National Park, Ualapue, Kawela, Pukoo, Kaunakakai, Halawa Valley and Kualapuu, according to the warning.

The weather service has also issued :—A flood advisory for the west side of the Big Island until 10 :45 a.m.;—A wind advisory until 6 p.m. today for Kauai and Niihau, predicting northeast winds 25 to 30 mph with localized gusts over 45 mph ;—A winter weather advisory for the Big Island Summits until 6 p.m. today, with snow accumulations of up to four inches and wind gusting as high as 65 mph.—High surf advisories for north and east shores from Niihau to Molokai, and for north and west shores of Maui until 6 p.m. Sunday. "A new north swell will rapidly build from northwest to southeast down the island chain today and tonight, hold through Sunday, then gradually lower early next week, " the advisory said. Surf will rapidly rise to 15 to 20 feet today along north shores of Niihau, Kauai, Oahu, and Molokai ; to 10 to 14 feet today along east shores of Niihau, Kauai, Oahu and Molokai ; and to 12 to 16 feet this afternoon along north shores of Maui.