Flash Flood Watch For Big Island: Wind Advisory, High Surf and Gale Warnings Extended

Rainbow Falls during rain storm/flash flood event on Oct. 24, 2017. Big Island Now Photo

3:43 PM HST Tuesday, Jan. 7, 2020: National Weather Service Honolulu

FLASH FLOOD WATCH IN EFFECT FOR THE BIG ISLAND FROM THURSDAY MORNING THROUGH SATURDAY EVENING

An unstable airmass will move over the islands during the second half of the week bringing an increase in shower activity. While showers will be possible over most areas, the most susceptible to flooding will be windward areas that have already received rain this week.

The extended period of rain could cause flooding in low spots, which could make some roadways impassable. Debris in streams and gulches may clog bridges and culverts. Strong winds may cause tree branches to fall which will add to the amount of possible debris.

PRECAUTIONARY/PREPAREDNESS ACTIONS

A flash flood watch means that conditions are favorable for flash flooding. Flash flooding is life threatening. Do not cross fast flowing water in your vehicle or on foot.

Monitor later forecasts and be prepared to take action if a flash flood warning is issued. If you experience heavy rain or rising water, head to higher ground immediately.

3:40 PM HST Tuesday, Jan. 7, 2020: National Weather Service Honolulu

WIND ADVISORY IN EFFECT FOR PARTS OF THE BIG ISLAND UNTIL 6 PM HST WEDNESDAY, HIGH WIND WARNING IS CANCELLED

What: Northeast winds 30 to 35 mph with gusts to 50 mph.

Where: Over and downslope of the Kohala mountains.

Impacts: Winds this strong can tear off shingles, knock down tree branches and make it difficult to steer high profile vehicles.

PRECAUTIONARY/PREPAREDNESS ACTIONS

Watch out for falling tree branches when walking or driving. Be prepared for power outages

3:38 PM HST Tuesday, Jan. 7, 2020: National Weather Service Honolulu

GALE WARNING NOW IN EFFECT UNTIL 6 PM HST THURSDAY

What: Northeast to east winds to 35 knots and seas 9 to 14 feet.

Where: Big Island Leeward Waters, Alenuihaha Channel, Pailolo Channel, Big Island Southeast Waters and Ma‘alaea Bay.

Impacts: Strong winds will cause hazardous seas, which could capsize or damage vessels.

PRECAUTIONARY/PREPAREDNESS ACTIONS

A gale warning means winds of 34 to 47 knots are imminent or occurring. Operating a vessel in gale conditions requires experience and properly equipped vessels. It is highly recommended that mariners without the proper experience seek safe harbor prior to the onset of gale conditions.

338 PM HST Tuesday, Jan. 7, 2020: National Weather Service Honolulu

HIGH SURF ADVISORY REMAINS IN EFFECT UNTIL 6 PM HST FRIDAY

What: Surf of 6 to 10 feet, rising to 8 to 12 feet Wednesday and possibly building to high surf warning levels Thursday and Friday.

Where: East-facing shores of the Big Island.

Impacts, Moderate: Expect strong breaking waves, shore break and strong longshore and rip currents making swimming difficult and dangerous.

Additional Details: The combination of high surf, strong onshore winds and elevated ocean water levels will result in beach erosion and waves to run up along east-facing shores later in the week when full moon high tides coincide with the elevated surf.

PRECAUTIONARY/PREPAREDNESS ACTIONS

Beachgoers, swimmers and surfers should heed all advice given by ocean safety officials and exercise caution. Know your limits and seek ocean recreation areas best suited for your abilities. When in doubt, don’t go out.