The tropical system churning along the east coast is showing signs of weakening, with the odds of a cyclone forming growing slimmer, National Hurricane Center forecasters said Monday evening.
A hurricane hunter plane sent to investigate the storm found the wave had not become any better organized during the day as expected. With the system set to face increasing wind shear that can shred storms, forecasters said the odds of a cyclone forming are diminishing. If a cyclone does form, they warned, it will likely happen over the next day as the storm slides along the North Carolina coast.
Without a defined structure, tracking the wave also becomes less certain, they warned, although they expect the wave to continue rolling to the northeast and back out to sea.
At 5 p.m., the system was located about 65 miles south of Charleston, South Carolina, and moving to the northeast at 12 mph. Tops winds remained at about 40 mph. A tropical storm warning covered much of the North Carolina coast, where the storm should arrive Tuesday. Tropical storm force winds extend outward about 85 miles from the storm’s center. Forecasters put the odds of a cyclone forming at 70 percent.
Even if no cyclone forms, forecasters warned the storm could still drop heavy rain. Last week as it meandered over South Florida, the system drenched the state, putting rain totals above historic averages. Parts of the Carolina coasts and southeast Virginia could get between three and six inches of rain, with up to nine inches possible in some locations, they said.
Meanwhile, Harvey continued crawling along the Texas coast, triggering “life-threatening” flooding, forecasters said in their 5 p.m. adivsory. Sustained winds remained at 45 mph, with the storm heading to the east, southeast at just 3 mph.
The storm is expected to begin turning toward the northeast Tuesday as it continues it slow trek, with the center moving off the central and upper Texas coast Tuesday night before it heads back inland over the northwestern Gulf coast near the Texas and Louisiana border on Wednesday.
Through Friday, Harvey is expected to drop between 10 and 20 additional inches of rain over the upper Texas coast and southwestern Louisiana, a slight decrease from earlier forecasts. However, some locations, including Houston and Galveston, may reach rainfall totals of 50 inches. Storm surge also remains a threat as Harvey churns along the coast, with levels between Corpus Christi and Galveston possibly reaching between one and three feet, forecasters warned. Tropical storm forces winds reach about 175 miles from Harvey’s center.
Forecasters also warned that a wave coming off Africa could become a cyclone over the next day or two in the eastern Atlantic. The system is moving to northwest at between 15 and 20 mph, heading toward weaker wind shear. Forecasters are giving the system an 80 percent chance of forming over the next five days.
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