Hurricane season is picking up. These conditions have forecasters most concerned.

After a slow but deadly start to hurricane season, the Atlantic Ocean is turning more active as the typical peak of activity approaches in September.

The season started with tropical storms Andrea, Barry and Chantal from June into July. The remnants of Barry contributed to a flooding disaster in Texas, while Chantal brought destructive impacts to North Carolina — storms linked by record amounts of moisture pulsing above the United States.

Then, earlier this week, Tropical Storm Dexter formed between North Carolina and Bermuda before tracking out to sea — a storm that may be a sign of things to come. Still, no storm has yet strengthened into a hurricane.

Now, a marine heat wave — or a long-lasting, expansive area of warmer-than-average seas — has developed in the western Atlantic and Gulf of Mexico. Marine heat waves fueled Hurricanes Helene and Milton last year, increasing the potential intensity of the storms and how much moisture they can carry.

These record-warm seas have meteorologists concerned.

In July, Defense Department meteorologist Eric Webb warned that atmospheric patterns may be more conducive than normal to storms making landfall along the East Coast this season.

“I’m honestly more convinced of that now than I was then,” Webb said this week in a message to The Washington Post, citing record-warm sea temperatures near the Eastern Seaboard and air pressure patterns that may guide storms toward land rather than out to sea.

As of early Thursday, the National Hurricane Center was monitoring two areas of interest for storm development in the Atlantic — one off the East Coast and another over the eastern part of the basin.

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What to know about storm threats

This week’s flooding rain in the Southeast can be partly linked to a tropical disturbance that remains offshore but is moving northward — and that will contribute to continued downpours in eastern North Carolina through Friday. After that, it will push farther offshore, with a 30% chance it could still strengthen into a tropical storm.

The other disturbance, currently in the open waters of the eastern tropical Atlantic, will probably remain away from land, curving into the central Atlantic through the weekend. The National Hurricane Center gives it a 60% chance of developing into a storm. The next names on the storm list are Erin, Fernand and Gabrielle.

After that, there’s a risk for additional storms in late August as a storm-enhancing pattern called the Madden-Julian Oscillation crosses Africa — the birthplace for disturbances that become hurricanes in the Atlantic. It’s too early to offer forecast specifics, but reliable models suggest conditions may lead to a notable uptick in activity after Aug. 15.

Meteorologists Michael Lowry and Andy Hazelton agreed there would be a likely turn toward a more active period across the Atlantic in the next week or two, with overall conditions becoming more conducive for developing storms.

Hazelton shared Webb’s concern that more storms could be steered toward the East Coast.

Ocean waters near Florida, the northern Bahamas and the western Caribbean Sea are most unusually warm — where the marine heat wave intensity registers as strong to locally severe (Level 2 or 3 out of 5). A buoy in the Florida Keys measured an ocean temperature of 99 degrees this past weekend. Ocean heat waves are growing longer and stronger as the climate changes.

In May, the National Oceanic and Atmospheric Administration said that there was a 60% chance for more storms than normal this season, a view shared by Colorado State University.

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Social media storms

Although no hurricanes have formed in the Atlantic yet this season, some posts making the rounds on social media have warned of strong storms possibly making landfall in the U.S. weeks into the future.

These posts can garner lots of attention but generally have no scientific value.

Some of these viral posts are based on interpretations of details in weather forecast models — but that doesn’t tell the whole story.

Because some weather models update every six hours and forecasts carry lots of uncertainty beyond a week, long-range predictions can swing dramatically from showing a big storm making landfall along the East Coast to nothing and back again in a matter of hours.

Hazelton said that he sees this every year as the tropics start to heat up, but he said it’s important for people to realize raw model forecasts more than 10 days out have little value and represent one of many possible scenarios.

“The proverbial butterfly flapping its wings today can mean your two-week hurricane may quickly evaporate by tomorrow,” Lowry said.

For forecasts beyond a week, meteorologists use an ensemble — a collection of models — to gauge general regional risks, but not landfall-level precision.

This year, there’s also a new tool for meteorologists and model watchers alike: artificial intelligence-driven forecast models that go out 15 days.

These provide yet another option in an already crowded predictive weather world. But, according to Lowry, they’re not helping the hurricane hype machine.

“The pervasiveness of AI has given the 15-day weather forecast an extra air of credibility,” Lowry said. But he added some of the latest AI weather models have blind spots.

Early studies have suggested these models can provide skillful forecasts of storm tracks but are not as reliable when it comes to intensity.

“Historically, 80% of hurricanes form between early August and mid-October and 90% of our strongest Category 3, 4 and 5 hurricanes form during this busy 10-week stretch,” Lowry said. “There’s no reason to think this year will be any different, so be ready regardless.”