Helene was a tropical storm in the Caribbean Sea early Wednesday Eastern time, the National Hurricane Center said in its latest advisory.
The tropical storm was accompanied by winds of 96 km/h. Follow our report here.
All times on the map are Eastern Time. By the New York Times
Where is flooding possible?
Storm surges are ocean waters pushed toward shore by storm winds. They have historically been the leading cause of hurricane deaths. If they occur during high tide, they can have far-reaching consequences.
Locations:
Where will it rain?
Flash flooding can occur inland and away from the storm center. Even weak storms can produce excessive rainfall that can flood low-lying areas.
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 is, the more likely it is that an eye will form in its center. When the eye appears symmetrical, it often means the storm is not encountering anything that could weaken it.
Helene is the eighth named storm to form in the Atlantic in 2024.
In late May, the National Oceanic and Atmospheric Administration predicted there would be between 17 and 25 named storms this year, a higher number than normal.
This season follows a very active year, with 20 named storms, including an early storm that was later given the official name “Unnamed.” This is the eighth consecutive year to exceed the average of 14 named storms. Only one hurricane, Idalia, made landfall in the United States.
Normally, the El Niño pattern that was in effect last season would have reduced hurricanes and the number of storms in a season. But in 2023, warmer Atlantic Ocean temperatures have dampened El Niño’s usual storm-thwarting effect.
The warm ocean temperatures that fueled the season last year have returned even warmer early this season, boosting forecasters’ confidence that more storms will occur this year. Rising sea surface temperatures could also strengthen storms more quickly than usual.
To top it all off, the El Niño phenomenon that was present last year is also weakening, most likely creating an atmosphere more conducive to the formation and intensification of storms.
Hurricanes need a calm environment to form, and in the Atlantic, a strong El Niño increases wind shear (a change in wind speed and/or direction based on height), disrupting a storm’s ability to regroup. Without an El Niño this year, clouds are more likely to reach the heights needed to support a powerful hurricane.
Sources and notes
Tracking card Tracking data comes from the National Hurricane Center. The map indicates probabilities of at least 5%. The forecast is for up to five days, starting three hours before the time the storm last reached its location. Wind speed probability data is not available north of 60.25 degrees north latitude.
Wind arrival 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 expected arrival times for high sustained winds of 58 mph (93 km/h) or greater for selected cities with a chance of reaching them. If high winds reach a location, there is no more than a 10% chance of arriving before the “earliest reasonable” time and a 50% chance of arriving before the “most likely” time.
Radar map The radar images come from the National Oceanic and Atmospheric Administration via Iowa State University. These mosaics are generated by combining individual radar stations that make up the NEXRAD network.
Storm surge map Storm surge data is from the National Hurricane Center. Forecasts are for the Gulf and Atlantic coasts, Puerto Rico, and the U.S. Virgin Islands only. Areas likely to experience flooding may differ from those shown on this map. This map accounts for tides, but not waves or flooding from rainfall. The map also includes intertidal areas, which are regularly flooded during typical high tides.
Satellite map The images are from the National Oceanic and Atmospheric Administration and the Japan Meteorological Agency via the Cooperative Institute for Atmospheric Research.
Precipitation map Data for multi-day forecasts or observed precipitation totals come from the National Weather Service. 1-day forecasts come from the National Oceanic and Atmospheric Administration.
