Tropical Storm Hernan formed in the Pacific Ocean and was not an immediate threat to land as a separate low-pressure system approached Hawaii with potential to deliver heavy rainfall, damaging surf and strong winds this weekend, forecasters said.
Where the systems are now
The Miami-based National Hurricane Center reported that Hernan was located roughly 2,350 kilometres west of the southern tip of Mexico's Baja California peninsula. The storm had estimated maximum sustained winds near 64 kilometres per hour and was tracking to the west.
At the same time, forecasters were monitoring a separate system identified as Potential Tropical Cyclone One‑C, centred about 1,247 kilometres east‑southeast of the main Hawaiian Islands. That disturbance carried winds around 64 kilometres per hour but was not yet organised enough to be officially classed as a tropical storm.
Forecast and expected impacts for Hawaii
Models and warnings indicated that the system could begin producing hazardous conditions across the Hawaiian chain as early as late Friday, with the risk increasing into Saturday. Forecasters said the southern portion of Hawai‘i Island — the Big Island — could experience conditions consistent with a tropical storm if the system makes landfall.
Rainfall totals were a primary concern. The National Hurricane Center forecast typical amounts of 13 to 25 centimetres across the island chain, with locally higher amounts up to 51 centimetres possible in some locations. Those totals raise the prospect of flash flooding and mudslides, particularly in steep terrain and areas recently affected by wildfire or where soils are already saturated.
- Timing: Hazardous conditions beginning late Friday and through Saturday for parts of the Hawaiian Islands.
- Rainfall: 13–25 cm commonly, with isolated amounts up to 51 cm.
- Winds: System currently around 64 km/h; may reach tropical‑storm strength at landfall in parts of the Big Island.
- Hazards: Flooding, mudslides, and dangerous surf.
Broader context
Hernan, while a named storm, remained well offshore and moving away from land. Meanwhile, activity in the Atlantic was also modest: Tropical Storm Cristobal had weakened to a depression and was forecast to dissipate, positioned several hundred kilometres west of the Azores and not threatening land, the centre said.
For residents and mariners in and around Hawaii, the evolving nature of the east‑central Pacific disturbance means conditions could change quickly. Emergency managers normally emphasise that rainfall-driven hazards such as flash flooding and landslides can occur even when winds remain below tropical‑storm strength.
| System | Approx. distance from land | Winds | Primary concerns |
|---|---|---|---|
| Hernan | ~2,350 km west of southern Baja California | ~64 km/h | Currently no land threat |
| Potential Tropical Cyclone One‑C | ~1,247 km ESE of Hawaii | ~64 km/h | Heavy rain, flooding, mudslides, dangerous surf |
| Cristobal (Atlantic) | ~982 km west of the Azores | Weakened to a depression | Expected to dissipate; no land threat |
What to watch and do
Those in Hawaii should monitor local forecasts from the U.S. National Weather Service and heed any watches or warnings. Preparations that reduce flood and landslide risk include ensuring drainage paths are clear, avoiding travel through flooded roadways, and having an evacuation plan for areas prone to rapid runoff. Boaters and beachgoers should be mindful of dangerous surf and rip currents as the system approaches.
At this stage, Hernan presents little immediate danger to coastal communities, but the separate Pacific disturbance nearer Hawaii warrants attention because of the heavy rain potential and attendant hazards. Forecasts can change as systems consolidate or interact with the atmosphere; staying informed through official updates is the best way to plan safely.
— Weather desk
