Weather

Two tropical systems are churning through the Atlantic Ocean and Caribbean Sea in the weeks leading up to the climatological peak of the hurricane season: Tropical Storm Dorian and Tropical Depression Six.

Tropical Storm Dorian was moving through the Windward Islands Tuesday morning, and as of the 11 am advisory from the National Hurricane Center, was producing winds up to 50 mph. A Hurricane Watch has been issued for Puerto Rico and the eastern third of the Dominican Republic.

Tropical Storm Dorian is moving steadily westward toward the Caribbean.

As of midday Monday, Tropical Storm Dorian was located 135 miles east-southeast of Barbados, and moving west-northwest at 14 mph. Tropical storm conditions are expected to arrive in the Windward Islands Monday evening, and the storm could become a hurricane over the northeast Caribbean by Tuesday evening.  

A tropical wave is becoming better organized just east of Miami, and the National Hurricane Center says a tropical depression or storm could form this weekend.

The system is not expected to be a significant threat to South Carolina, but periods of heavy rain and unsettled seas are possible along the immediate coast early next week.

Forecasters at the National Hurricane Center increased the odds of development to 90 percent in their 2 pm Friday tropical outlook.

System Likely Stays Offshore

More than 85 percent of all hurricane activity in the Atlantic Basin occurs after the middle of August.

Some consider Aug. 15 as the “real” start to hurricane season. To others, like former FEMA administrator Craig Fugate, it’s synonymous with the start of football season.
 

Thunderstorms are likely to become more widespread across the Palmetto State over the next three days, thanks to an approaching front. The storms will provide some relief from the heat, but a few of them may become strong enough to produce damaging wind gusts and flash flooding.
 

The chances for above normal hurricane activity in the Atlantic Basin this year have increased according to the newly-released seasonal update from NOAA.

The agency also said El Nino — a climate phenomenon that warms the water in the eastern Pacific Ocean and often reduces hurricanes in the Atlantic — has officially ended. This is the primary reason for the higher chance of more tropical activity.
 

The most active part of the hurricane season are the months of August, September, and October. In this “State of the Season” report, we will assess trends in atmospheric and oceanic conditions around the globe that may lend clues on how the waters could behave over the next few weeks.

The Season So Far

The most active part of the hurricane season often begins in August. Right on-cue, at least one tropical system is likely to form in the Atlantic by the upcoming weekend.

System Near Florida Only a Rain-Maker

Update Tuesday 2:00 p.m. ET:

A Severe Thunderstorm Watch has been issued for eastern South Carolina until 10 p.m. A line of strong to severe thunderstorms are developing along and southeast of a cold front moving south towards the Lowcountry. Scattered damaging wind gusts up to 70 mph and a tornado or two are possible.

Update Tuesday 11:30 a.m. ET:

The large heat dome that has prompted the issuance of heat advisories and warnings over a large swath of the central and eastern United States is making its presence felt here in South Carolina.

Widespread temperatures in the mid to upper 90s, along with high humidity, will result in heat indices around 105 degrees over the Midlands and Low Country. The greatest combination of heat and humidity is forecast over the Pee Dee and Grand Strand regions, where the National Weather Service has issued heat advisories. Heat indices are forecast to reach 108 degrees in the advisory area.

The heart of hurricane season is approaching, and the atmosphere is signaling that the Atlantic Basin could soon become more active.

No development is expected over the next week to ten days. However, later this summer and fall, global-scale climate factors are changing. And this could make conditions more favorable for tropical storm or hurricane development.

Forecasters examine many features when forecasting for the tropics. They include: wind shear, water temperatures, atmospheric dust concentrations, moisture in the air, and global atmospheric circulations.

Tropical Storm Barry is intensifying as it moves slowly toward the Louisiana Gulf coast.

Barry was located 100 miles southwest of the mouth of the Mississippi River, according to the advisory issued by the National Hurricane Center at 11 am Friday. The warm waters of the Gulf of Mexico should encourage the system to intensify, but dry air high above the storm and wind shear have prevented rapid strengthening so far. Forecasters expect Barry to be near hurricane intensity as it makes landfall Saturday morning along the Louisiana coast.

The National Hurricane Center says the tropical system in the Gulf of Mexico is now Tropical Storm Barry, and it could become a hurricane before hitting Louisiana this weekend.

A low that is over South Carolina and Georgia on Monday morning is likely to become a tropical depression later this week as it moves south into the northern Gulf of Mexico.

Update Thursday 2:30 pm ET:  Thunderstorms are blossoming across South Carolina at this hour.  The strongest activity was noted on radar north of Columbia, near Rock Hill and Lancaster, where several Severe Thunderstorm Warnings have been issued.  Another strong cluster of storms have developed in the Pee Dee region just inland from Georgetown and Myrtle Beach.  The storms are expected to continue developing across the Palmetto State this afternoon, capable of producing wind damage, dangerous cloud-to-ground lightning and very heavy rain.