Tropical storm watches are up for Florida’s eastern coast, and the National Hurricane Center said Friday that Isaias had grown into a hurricane and could impact the rest of the East Coast early next week.
Hurricane warnings were posted for the Bahamas, and Isaias, whose strength has exceeded earlier forecasts, could become a Category 3 storm with peak winds of 100 mph Saturday.
Tropical storm conditions could reach Florida on Saturday, the hurricane center said, generating rains of 3 to 6 inches, and the storm is forecast to make a sharp northward turn and parallel the coast.
That would put it on a path to have some impact on the Philadelphia region, particularly at the shore, with the primary threat being heavy rains, given all the juice over the very-warm Atlantic.
The local National Weather Service office is watching the storm, but it’s way too soon to know precisely where it will go, said meteorologist Patrick O’Hara. Isaias was getting roughed up during its encounter with the terrain of the Caribbean islands, and that ultimately will affect its path.
Whatever else Isaias does or doesn’t do, it has set another record. It became the ninth named storm of the season, which hasn’t occurred this early in the Atlantic Basin in the satellite period dating to the 1960s. To earn a name, a storm needs peak winds of 39 mph.
The previous record was held by Irene, which formed on Aug. 7, 2005, said hurricane center spokesperson Dennis Feltgen. That’s not to be confused with the Irene of 2011 that set off widespread flooding around here. The Irene of 2005 was essentially a fish storm that stayed out over the Atlantic, but it would be followed by the devastating Katrina.
And a disturbance off the west African coast has a 50-50 chance of growing into Jose, the center says.
The standing record for a No. 10 in the basin, which includes the Caribbean and the Gulf of Mexico, would be Aug. 22, said Colorado State University hurricane expert Philip Klotzbach.
His forecast as of earlier this month called for 20 named storms; the average is 11. Of those, nine were expected to grow into hurricanes with peak winds of 74 mph or better, with four of those becoming major ones, which have winds of at least 111 mph. The averages are six hurricanes and two majors.
In the meantime, Philadelphia almost certainly will see some rain between now and whenever Isaias approaches. Heavy rains are possible from early Friday into the afternoon, and shower chances remain in the forecast every day through Wednesday.
And for something completely different: The high Friday might struggle to make it to 80, breaking a two-week string of above-normal temperatures in one of the warmest Julys on record.