Isaias has been downgraded to a Tropical Storm as of the 5:00 p.m. advisory. The center is crrently over portions of the Bahamas, will move very close to the Florida’s East Coast tonight into Sunday, lashing the coastline with high winds and dangerous storm surge of 3 to 5 feet above ground level. Isasias has weakened and become disorganized with interaction from land across the Bahamas and drier air moving into the system.
As Isaias it moves into very warm water (85-degree sea surface temperatures,) and interacts with the gulf stream, some strengthening is expected until a trough approaches the east coast and southwesterly wind shear takes place. This will also help to speed up the hurricane until it reaches Eastern North Carolina, however, it could decrease in speed as it interacts with land and slowly becomes an extra-tropical system by midweek. Tropical Storm watches and warnings are likely over the next day for late Monday into Tuesday along the entire Mid-Atlantic coastline.
Rain will begin across the Lower Mid-Atlantic late Monday as an easterly wind takes over. This will also help with orographic lift across the mountains and heavy rain will develop in these locations first. Then, the Carolina’s and Central and Eastern Virginia will see rain develop as the center of Isaias moves north-northeastward across Eastern North Carolina into Hampton Roads and the Mouth of the Chesapeake Bay late Monday night into the day on Tuesday.
Our latest rainfall forecast is blended with all forecast models. It should be noted that if the system is slower than expected, higher rainfall totals are more likely. At this time, we are forecasting 3 to 6 inches with locally higher amounts near and just east of the I-95 corridor, to the north and west of the center of Isaias. On the east side of the system, rain bands will produce potential severe thunderstorms which will likely cause locally heavy rainfall and the chance for a few isolated tornadoes.