HONOLULU — A Pacific storm system that forecasters are tracking could threaten the Hawaiian Islands by the weekend, the National Hurricane Center said Wednesday, raising the prospect of significant rainfall, flooding and mudslides across the state.
What forecasters say
The NHC initiated advisories on Potential Tropical Cyclone One-C, which it placed at roughly 1,000 miles east-southeast of the Hawaiian Islands with maximum sustained winds of about 35 mph. The system was moving west and was expected to strengthen into a tropical storm before nearing the islands by late Friday.
Officials wrote that a hurricane watch or tropical storm watch will likely be needed for parts of the state by early Thursday. The system could produce widespread downpours, with forecast rainfall of 5 to 10 inches across the island chain and isolated totals up to 20 inches, conditions that "could produce flooding and mudslides," the NHC said.
Atlantic system poses no threat to Hawaii
Meanwhile, the National Hurricane Center reported that Tropical Storm Cristobal formed in the Atlantic Ocean well west of the Azores. Cristobal was centered about 880 miles west of the Azores with sustained winds of 45 mph, moving east. There were no coastal watches or warnings in effect for Cristobal, and it was forecast to dissipate on Thursday.
Local impacts and preparedness
The forecast rainfall amounts for the Pacific system are sufficient to cause urban and flash flooding, especially in low-lying areas and places with poor drainage. Heavy rains on steep slopes increase the risk of mudslides and debris flows, particularly in areas burned by past wildfires where vegetation that holds soil in place has been reduced.
Residents should review local emergency plans and be ready to respond quickly to watches and warnings that may be issued. Practical steps include:
- Securing loose outdoor items and checking drains and gutters.
- Having emergency supplies ready for at least 72 hours, including water, medications and important documents.
- Avoiding driving through flooded roads; a few inches of moving water can sweep a vehicle off the road.
- Monitoring official channels — the National Weather Service office in Honolulu and county emergency management — for updates and evacuation instructions.
Timeline and watches
The NHC said advisories for the Pacific disturbance began Wednesday. Forecasters expect the system to strengthen into a tropical storm prior to near-island impacts late Friday; as a result, formal watches — which alert the public to the possibility of tropical-storm- or hurricane-force conditions — were likely to be required by early Thursday for portions of the state.
Because of uncertainties in storm intensity and exact track, residents should pay attention to updates. Small shifts in the system's path could markedly change local wind and rain impacts on individual islands and communities.
Brief data snapshot
| System | Location (approx.) | Winds | Forecast |
|---|---|---|---|
| Potential Tropical Cyclone One-C | ~1,000 miles ESE of Hawaii | 35 mph | Expected to strengthen; near islands by late Friday; watches likely by Thursday |
| Tropical Storm Cristobal | ~880 miles W of the Azores | 45 mph | Moving east; no watches/warnings for U.S.; forecast to dissipate Thursday |
Forecasters emphasized rainfall as the chief hazard for the Hawaiian Islands from the Pacific system, with potential accumulations that could exceed local drainage capacity. State and county emergency managers will determine whether to issue watches or warnings as the system approaches and models refine the track and intensity forecasts.
WE NEWS will continue to monitor advisories from the National Hurricane Center and local emergency agencies and will publish updates as conditions evolve.
