SUMMARY OF WATCHES AND WARNINGS IN EFFECT:
A Tropical Storm Watch is in effect for…
A tropical storm watch means that tropical storm conditions are possible in the watch area. A watch is typically issued 48 hours before the anticipated first occurence of tropical-storm-force winds, conditions that make outside preparations difficult or dangerous.
Interests on Kauai and Niihau should monitor the progress of Olivia.
For storm information specific to your area, please monitor products issued by the National Weather Service office in Honolulu Hawaii.
DISCUSSION AND OUTLOOK
At 11 p.m. HST (0900 UTC), the center of Hurricane Olivia was located near latitude 21.7 North, longitude 146.9 West. Olivia is moving toward the west near 9 mph (15 km/h). This general motion is expected to continue through early Monday, followed by a turn toward the west-southwest starting late Monday. This west-southwest motion is expected to continue through Tuesday evening. On this forecast track, tropical storm conditions are possible over some parts of Hawaii starting Tuesday.
Maximum sustained winds measured by Hurricane Hunter aircraft are near 85 mph (140 km/h) with higher gusts. Little change in strength is forecast through late Monday, with gradual weakening possible starting sometime on Tuesday.
Hurricane-force winds extend outward up to 30 miles (45 km) from the center and tropical-storm-force winds extend outward up to 120 miles (195 km).
The estimated minimum central pressure is 980 mb (28.94 inches).
HAZARDS AFFECTING LAND
WIND: Tropical storm conditions are possible within the watch area starting Tuesday.
RAINFALL: Olivia is expected to produce total rainfall accumulations of 10 to 15 inches. Isolated maximum amounts of 20 inches are possible, especially over windward sides of Maui and the Big Island. This rainfall may produce life-threatening flash flooding.
SURF: Large swells generated by Olivia are expected to continue to increase across the main Hawaiian Islands. Surf will build as Olivia approaches, and may become damaging along some exposed east facing shorelines starting Tuesday or Wednesday.
Vertical wind shear remains relatively weak in the vicinity of Olivia. Water temperatures, as well as ocean heat content values, are expected to increase along the forecast track. Therefore, Olivia will likely remain a hurricane through 36 hours. After that, increasing vertical wind shear is forecast to take its toll on Olivia, so that it may be a strong tropical storm within 48 hours. Additional slow weakening is expected to persist during days 3 through 5. The latest forecast is close to the IVCN and CTCI. Note that based on the latest track and intensity along with the wind speed probabilities, Tropical Storm Warnings will likely be required for portions of the Hawaiian Islands on Monday.
1. It is important to not focus on the exact forecast track and intensity when planning for Olivia. Persons on all of the main Hawaiian Islands should continue preparing for the likelihood of direct impacts from this system Monday and early Tuesday. Those impacts could include intense flooding rainfall, damaging winds, large and dangerous surf, and storm surge.
2. Regardless of the exact track and intensity that Olivia takes as it approaches the islands, significant effects often extend far from the center. In particular, the mountainous terrain of Hawaii can produce localized areas of strongly enhanced winds and rainfall, even well away from the tropical cyclone center.
This is a Civil Defense Hurricane Olivia update for 10:30 a.m., Sunday, September 9, 2018
The Central Pacific Hurricane Center reports that as of 5 a.m., Hurricane Olivia is a Category 1 hurricane, 735 miles ENE of Hilo with sustained winds of 75 mph, moving W at 16 mph.
It is still too early to know what effects this hurricane will have on Hawaii Island. There are no warnings or advisories in effect at this time.
The County will not be distributing sandbags until active flooding occurs. Please take the necessary precautions to prepare your property if you live in a flood prone area, and secure your vessels in harbors. This is also a good time to make sure your emergency plans are updated.
More information on hurricane preparedness can be found here: www.hawaiicounty.gov/emergency…
Civil Defense is monitoring the storm and will keep you informed of any changes that may affect your safety.
Actions to take whenever a tropical storm or hurricane nears Hawaii
All of Hawaii’s citizens should know what to do during a hurricane, tropical storm watches and warnings. Watches and warnings are prepared for the Hawaiian Islands by the National Weather Service Central Pacific Hurricane Center in Honolulu. When watches and warnings are issued, people should closely monitor the Internet, radio, TV, or NOAA Weather Radio for official bulletins of the storm’s progress and instructions from civil defense authorities. Jim Weyman, director of the Central Pacific Hurricane Center, said, “Although you and your family may have never experienced a hurricane, don’t be complacent! It’s not a matter of if a hurricane will occur, but when one will occur. All of the Hawaiian Islands are at risk for a hurricane and we should all know what actions to take.”
For the Central Pacific Ocean a Hurricane/Tropical Storm Watch means hurricane/tropical storm conditions are possible in the specified area of the Watch, usually within 48 hours.
When a Hurricane or Tropical Storm Watch is issued:
For the Central Pacific Ocean a Hurricane/Tropical Storm Warning means hurricane/tropical storm conditions are expected in the specified area of the Warning, usually within 36 hours.
When a Hurricane or Tropical Storm Warning is issued:
The Central Pacific Hurricane Center (CPHC) issues tropical cyclone warnings, watches, advisories, discussions, and statements for all tropical cyclones in the Central Pacific from 140 Degrees West Longitude to the International Dateline. The season officially begins on June 1 and ends on November 30. However, tropical cyclones can occur at any time. The National Weather Service Forecast Office in Honolulu activates the CPHC when: (1) a tropical cyclone moves into the Central Pacific from the Eastern Pacific, (2) a tropical cyclone forms in the Central Pacific, or (3) a tropical cyclone moves into the Central Pacific from the West.
For links to the latest weather forecasts, reports, radar, webcam and satellite imagery visit our Weather Page at hawaii247.com/weather