A tropical storm warning was issued Wednesday morning for Florida’s Big Bend as a depression showed signs of intensifying in the Gulf of Mexico.
Over the next day or two, the National Hurricane Center said the tropical depression is expected to grow more organized and make a northeast turn toward Florida’s Gulf Coast, raising the risk of storm surge and flooding in Tampa and other low-lying coastal areas. A hurricane watch for the area was issued on Tuesday night.
As the storm — expected to be named Hermine if it strengthens a bit over the next day or so — tracks to the northwest, it’s expected to continue sweeping thunderstormsinto South Florida through the week, National Weather Service Miami meteorologists said.
Squalls could carry heavy thunderstorms and heavy rain, increasing the risk of flooding, particularly in Southwest Florida, where two to five inches of rain in recent days has left the ground saturated. A flood watch was issued for most of South Florida, except parts of Monroe County on the mainland.
In an advisory issued at 5 a.m. Wednesday, the National Hurricane Center forecasters said the storm was located about 420 southwest of Tampa, with sustained winds of 35 mph. The storm was crawling slowly into the Gulf, where warm water awaits and the threat of increasing thunderstorms mounts.
Over the last week, the depression danced back and forth, repeatedly threatening to intensify overnight when thunderstorms increase, then encountering stifling wind shear and dry air. Computer models that struggle to forecast weaker systems have also vexed forecasters.
“Two highly reliable models were saying the exact opposite, and then they flip flopped. Now neither of those models say it’s going to become a hurricane,” said NHC senior hurricane specialist Stacey Stewart.
For much of the weekend, the messy storm pounded Cuba with torrential rain. Between seven and eight inches fell in the Artemisa province in the northwest part of the island. To the south and west, heavy rain also soaked the provinces of Cienfuegos and Pinar del Rio. CubaDebate, a government-affiliated website, reported no injuries or damage linked to the weather Tuesday.
The mountainous island has probably helped shred the storm somewhat, raising concern that, as it pulls away, the depression could power up.
In a Monday blog, Weather Underground meteorologist Jeff Masters said the center of the storm also had the potential to shift to the south, “so that it is closer to the heaviest thunderstorms near the western tip of Cuba. If this occurs, a southward shift in the predicted track of [the tropical depression] may be required.” That track could move the storm closer to the low-lying Tampa area, where storm surge and flooding become a bigger danger.
Forecasters are also watching another tropical depression nearing the Carolina coast. At 11 p.m., the storm was located about 115 miles off Cape Hatteras and was expected to move off shore. Up to three inches of rain could fall over the region, with as much as five inches in some locations.The north coast of North Carolina, from Cape Lookout to the Oregon Inlet, along with Pamlico Sound, was under a tropical storm warning Tuesday morning, with stormy conditions possible in 12 hours.
Hurricane Gaston also remained far off U.S. shores, about 750 miles east of Bermuda. Sustained winds picked up to 120 mph at 11 p.m. Tuesday as the storm moved east. It is expected to speed up over the next couple of days but not get much stronger and likely fizzle in about five days.
Staff writer Mimi Whitefield contributed to this report.
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