Rapid intensification can make hurricanes more dangerous in a short period, leaving less time for preparation and response. For coastal and island communities like the U.S. Virgin Islands and Puerto Rico, early and accurate forecasts are critical when weather conditions allow a cyclone to strengthen quickly.

The Source contacted Alex DaSilva, lead hurricane expert at AccuWeather, to better understand what drives rapid intensification of cyclones and why it can pose such a serious risk to vulnerable areas.

Rapid Intensification of Cyclones Explained

“Rapid intensification occurs when a storm’s winds increase by at least 30 knots, or 35 mph, within a 24-hour period,” DaSilva said. “It requires prime atmospheric conditions and warm water temperatures. The water temperature needs to be at least 80 degrees Fahrenheit for tropical development.”

A key factor, DaSilva explained, is not just warm water at the surface but warm water extending hundreds of feet below. Meteorologists track this using a metric called “Ocean Heat Content.”

“Warm water temperatures at the surface and hundreds of feet below the surface are the primary driving function for rapid intensification,” DaSilva explained. “Meteorologists also look for the ‘Ocean Heat Content,’ which essentially is the depth of the warm water,” he added.

“Ocean Heat Content is very well correlated with an increasing chance of rapid intensification. In other words, the greater the Ocean Heat Content, the greater the chance you have of seeing rapid intensification.”

DaSilva identified several regions where Ocean Heat Content is especially high.

“The highest Ocean Heat Content is typically in the Gulf and in the western and central Caribbean,” he said. “There is also relatively high Ocean Heat Content off the southeast coast of the U.S. and even into the eastern Caribbean.”

He added that rapid intensification also depends on conducive atmospheric conditions and specifically a moist environment and minimal wind shear.

“For intensification to occur, you need an air mass that’s very moist, because storms can’t develop with dry air masses,” DaSilva noted. “Saharan dust coming from Africa can inhibit tropical development, and wind shear – which is the change in wind direction and wind speed at different heights in the atmosphere – is another big factor for rapid intensification.”

DaSilva offered a helpful analogy to explain how wind shear disrupts storm structure.

“Tropical systems can intensify when thunderstorms go straight up into the atmosphere, but wind shear can lean those thunderstorms over and even knock them over,” DaSilva explained. “I always like to think of this process as like a stack of pancakes. You want your stack of pancakes to stand nice and tall, but when there’s wind shear, it disrupts that stack of pancakes and can knock it over. When there is no wind shear and warm ocean waters, you have a prime environment for rapid intensification.”

A recent example of a storm that underwent explosive strengthening is Hurricane Erick, which formed in the eastern Pacific and made landfall along Mexico’s Pacific coast on June 19, 2025.

“Hurricane Erick in the Pacific went from a tropical storm to a Category 4 hurricane in about 24 hours, and that is an impressive case of rapid intensification,” DaSilva recognized.

Challenges with Forecasting Rapid Intensification

 DaSilva acknowledged that even when all of the conditions are in place for rapid development to occur, it doesn’t always occur. It can be difficult for meteorologists to pinpoint exactly when — or if — a cyclone will suddenly strengthen.

“It’s important to make this point: just because you have all those ingredients does not guarantee that a storm will rapidly intensify. There are internal mechanisms with these tropical systems that can make it a little bit difficult to predict at times,” DaSilva admitted.

He noted that even with perfect atmospheric conditions, some storms fail to organize structurally, which is a key requirement for intensification.

“Sometimes you can have all the necessary atmospheric conditions needed for rapid intensification in place, but it just doesn’t happen. Many times, it just has to do with the fact that the storm can’t get the fundamental organization down. If that doesn’t happen, the storm won’t be able to intensify.”

Forecasting tools have improved significantly, but there are still limitations, especially when it comes to detecting rapid changes in intensity. Even with cutting-edge tools, experience and pattern recognition often make the difference.

“Most of the time, the forecast models are not that great at picking up on rapid intensification, and some models have been struggling with predicting rapid intensification,” DaSilva stated. “Forecasters are very good at predicting the track of a storm, and the science has evolved so much in the last 10 to 15 years. Forecasts predicting intensity have improved over the years, but not as much as our track forecasts.”

“Many times, it comes down to the intuition and experience of the meteorologists analyzing the data and models, using new tech and old-fashioned meteorology. It’s important to know the basics and pattern recognition. In some cases, old-school meteorology can outperform some of those newer models,” DaSilva shared.

Looking ahead, DaSilva said, while a perfect forecast may never be possible, experts are getting better at spotting favorable conditions in advance.

“I don’t think we’ll ever be able to predict with 100% certainty if and when rapid intensification will happen. What we can predict is when environmental conditions and factors are more or less conducive for rapid intensification. We’ve been getting much better at doing that over the last few years.”

Preparing for Rapid Intensification

DaSilva advised individuals to be as prepared as possible in the event that a storm rapidly intensifies. Given the unpredictability of such events, he recommends planning for a storm one category higher than what is currently forecast.

“I always tell people to prepare for at least one category higher than what the storm is currently forecast when it’s passing your area or expected to make landfall,” DaSilva advised. “If we’re forecasting a Category 1 hurricane, it’s best to prepare for at least a Category 2 storm. It’s always good to be extra-prepared, especially in this day and age where we’re seeing more cases of rapid intensification,” he continued.

“It’s always better to be overprepared than underprepared. You don’t want to be trapped or caught off guard last minute if a storm rapidly intensifies. So again, we’re urging everyone to follow the forecast very carefully,” DaSilva said.

Indeed, early preparation is critical, particularly as experts warn that some long-standing tools used to detect rapid intensification are being scaled back.

According to DailyClimate.org, NOAA and the Department of Defense are ending data collection from aging polar-orbiting satellites that have tracked hurricanes since the early 2000s. These weather satellites carry microwave sensors that help meteorologists “see” inside storms, especially at night, when hurricanes often strengthen over warm waters.

A report by The New York Times added that this type of microwave data is one of the most reliable ways to assess storm structure and intensity, especially when storms are far from land and out of range of aircraft. Losing or limiting access to these observations could lead to forecast delays or reduced accuracy during critical periods of storm development.

While some international satellites will continue to provide similar data, meteorologists say the gaps in coverage may leave forecasters with fewer early warning signs, increasing the importance of local readiness and public awareness.

Concerns for the 2025 Hurricane Season

DaSilva explained that meteorologists are closely monitoring conditions across both the Atlantic basin and the Eastern Pacific basin, where there is potential for storms to strengthen quickly.

“We are very concerned about more cases of rapid intensification in the Atlantic and the Pacific this year,” DaSilva said. “Cases of rapid intensification have been occurring more frequently, and I think there is a link to climate change, primarily due to rising ocean temperatures and higher Ocean Heat Content.”

So far this year, the Eastern Pacific basin has seen a much more active start to the hurricane season, with six named storms recorded as of Tuesday. Meanwhile, the Atlantic has remained relatively quiet, with only two short-lived cyclones developing. DaSilva noted that the activity in one basin does not necessarily predict what will happen in the other.

“We don’t believe there’s much of a correlation between the Atlantic and the Pacific. We’ve seen a very active start to the Pacific season, so that usually means the Atlantic will be quiet for the time being,” DaSilva said. “It’s very difficult to have both the Atlantic and Pacific basins extremely active at one time, and usually, it’s one or the other. Overall, the active start to the eastern Pacific season doesn’t really say a whole lot about whether we’re going to see a busy Atlantic season,” he added.

While some current conditions may reduce the chance of rapid intensification near the U.S. Virgin Islands, residents should remain watchful. DaSilva said recent ocean data offers some cautious optimism.

“There’s always a risk of rapid intensification every hurricane season, but I am feeling a bit better looking at the water data east of the islands,” DaSilva affirmed.

“The Ocean Heat Content east of the Lesser Antilles is actually a little below average for this time of the year because the Bermuda High has been stronger. The trade winds have also been stronger, which has mixed up some of the water,” said DaSilva. “We’ve also seen a lot of Saharan dust this year, which has filtered some of the sunlight and caused sea surface temperatures and Ocean Heat Content to be a little bit on the lower side. These factors can help prevent rapid intensification.”

Still, DaSilva warned that even with lower water temperatures, storms could form later in the season.

“It does not look like this is going to be a repeat of the 2017 season, when we saw two destructive Category 5 hurricanes impact the islands,” DaSilva said. “That said, I am concerned about the possibility of at least one or two impacts on the Virgin Islands or Puerto Rico this hurricane season. The pattern still supports at least a storm or two coming through that area,” he warned.

“However, the good news is that the water temperatures don’t look to be as warm as the last couple of years, which might be able to prevent rapid intensification. This doesn’t guarantee we won’t see it, but it does lower the risk.”

DaSilva encouraged residents to stay engaged with forecasts, especially as conditions may become more favorable for development west of the islands.

“It’s important for everyone in the U.S. Virgin Islands and Puerto Rico to follow forecasts very closely and not tune out, because storms can evolve and change quickly,” DaSilva said. “We expect the risk of rapid intensification to be focused west of the U.S. Virgin Islands this year, more toward the Gulf or western Caribbean, because the Ocean Heat Content and sea surface temperatures are higher in that area. That does not guarantee the U.S. Virgin Islands won’t face a rapidly intensifying storm. My concern is that we could see an active second half to the hurricane season.”

A Potentially Busy Second Half of Hurricane Season

DaSilva reminded individuals that AccuWeather is forecasting 13 to 18 named cyclones in the Atlantic basin this year, which is above the historical average. The outlook has remained consistent since it was first issued in March.

“We’re forecasting more named storms than the historical average,” he said. “The El Niño Southern Oscillation continues to be neutral, and it’s expected to be neutral throughout most of the hurricane season,” stated DaSilva. “However, it might turn toward La Nina late in the season. If that happens, we could see a busy end to the hurricane season, similar to what we saw last year with several storms during the month of November.”

Although November storms tend to form closer to the United States, DaSilva cautioned that the Caribbean is not immune.

“Luckily for the U.S. Virgin Islands, there typically aren’t many tropical threats for the eastern Caribbean region during the month of November,” he said. “They’re usually closer to the United States. But we have seen storms in the eastern Caribbean during November, so we still need to keep a close eye out for that.”

Finally, DaSilva highlighted another factor that could shape the latter part of the season: water temperatures near the coast of Africa.

“We’ll be keeping a very close eye on the water temperatures off the coast of western Africa,” he said. “When the waters are cooler in that area, that can suppress Atlantic tropical development in the Main Development Region. When those temperatures are warmer, it can enhance development. Right now, those waters are cool, and that’s why we really haven’t seen too much action way out in the Atlantic. That could change later in the season. Waters in this region have the potential to warm up in the coming weeks and months,” DaSilva concluded.

Weather Forecast Information

As of Tuesday afternoon, the NHC is monitoring several disturbances across both the Atlantic Basin and Eastern Pacific Basin. At this time, no cyclones are expected to form near the USVI or Puerto Rico. However, a tropical wave is forecast to pass through the Caribbean later this week. USVI visitors and residents are encouraged to prepare for hurricanes now, before any cyclones are on the horizon.

In addition to obtaining weather information from the NHC, the NWS, and NOAA, the local weather forecast for the U.S. Virgin Islands is regularly updated on the Source Weather Page and VI Source YouTube Channel. Individuals can also find helpful weather information and alerts from the Virgin Islands Territorial Emergency Management Agency.