Iona was a Category 1 hurricane in the North Pacific Ocean Monday morning Eastern time, the National Hurricane Center said in its latest advisory.

Forecast wind speeds and direction

Iona became the first named storm of the 2025 hurricane season in the Central Pacific on Sunday evening local time. The storm was over the ocean southeast of Hawaii, with maximum sustained winds of 75 miles per hour.

The National Hurricane Center said it was expected to move steadily westward over the next several days, staying well south of Hawaii. It was not expected to threaten land, and no warnings or watches were in effect.

Where will it rain?

Flash flooding can occur well inland and away from the storm’s center. Even weaker storms can produce excessive rainfall that can flood low-lying areas.

1-day forecast precipitation

Tracking Iona’s rainfall

When a storm comes close enough to land, signals from the United States radar network will begin to bounce off the rainfall within a tropical cyclone, making it easier to locate the more intense section of the storm and the heaviest rainfall. During hurricanes, the storm’s center will be the area on radar void of rain called an eye and completely encircled by the most intense winds and rain called the eye wall. Spiraling out from the center will be bands of rain that vary in intensity.

Tracking power outages

The damaging winds from Iona caused power outages along the storm’s path.

Share of customers without power

What does the storm look like from above?

Satellite imagery can help determine the strength, size and cohesion of a storm. The stronger a storm becomes, the more likely an eye will form in the center. When the eye looks symmetrical, that often means the storm is not encountering anything to weaken it.

Storms often come close to Hawaii and affect the weather, but a direct landfall of a named storm on a Hawaiian island is rare since the land area is relatively small. Even a brush from one of these storms can cause problems. In 2020, Hurricane Douglas didn’t make a direct hit on the islands, but it produced damaging winds.

Typically, storms in the North Central Pacific that have wandered in from near North America keep their original names, as determined by the World Meteorological Association. Storms are given a traditional Hawaiian name when they form in the Central Pacific.

Sources and notes

Tracking map Tracking data is from the National Hurricane Center. The map shows probabilities of at least 5 percent. The forecast is for up to five days, with that time span starting up to three hours before the reported time that the storm reaches its latest location. Wind speed probability data is not available north of 60.25 degrees north latitude.

Intensity chart Best track and forecast path are from the National Hurricane Center.

Wind arrivals table Arrival times are generated from a New York Times analysis of National Hurricane Center data. Geographic locations use data from the U.S. Census Bureau and Natural Earth. Time zones are based on Google. The table shows predicted arrival times of sustained, damaging winds of 58 m.p.h. or more for select cities with a chance of such winds reaching them. If damaging winds reach a location, there is no more than a 10 percent chance that they will arrive before the “earliest reasonable” time and a 50 percent chance they will arrive before the “most likely” time.

Radar map Radar imagery is from the National Oceanic and Atmospheric Administration via Iowa State University. These mosaics are generated by combining individual radar stations that comprise the NEXRAD network.

Storm surge map Storm surge data is from the National Hurricane Center. Forecasts only include the United States Gulf and Atlantic coasts, Puerto Rico, and the U.S. Virgin Islands. The actual areas that could become flooded may differ from the areas shown on this map. This map accounts for tides, but not waves and not flooding caused by rainfall. The map also includes intertidal areas, which routinely flood during typical high tides.

Rip currents map Rip current data is from the National Hurricane Center. Rip current risk shown is not always associated with active tropical cyclones.

Satellite map Imagery is from the National Oceanic and Atmospheric Administration and Japanese Meteorological Agency via the Cooperative Institute for Research in the Atmosphere.

Precipitation map Data for multi-day forecasts or observed rainfall totals are from the National Weather Service. The 1-day forecast is from the National Oceanic and Atmospheric Administration.

Historical map Storm paths are from the National Oceanic and Atmospheric Administration’s HURDAT database. Only storms with names that formed after the year 2000 and that are within 50 miles of the potential landfall location are shown.

Note: All basemaps are built with Daylight (urban areas); Natural Earth (roads, labels, terrain)