Outer Bands From Ida May Affect Upstate Tuesday
Update as of 9am Tuesday:
The center of Ida is still on track to pass west of the state on Tuesday, but rain bands well east of the center are expected to affect mainly the Upstate.
The most likely area for heavy rain and flash flooding is in the Escarpment area, where Flash Flood Watches are in effect for Oconee, Pickens, and a small portion of Greenville county in the mountains. 1 to 3 inches of rain are forecast over much of the Upstate, with 3 to 6 inches possible near the border of North Carolina.
An isolated tornado or two is still possible Tuesday afternoon and night, primarily in the Upstate region. However, the air is not forecast to be as unstable as it was with Fred two weeks ago. As a result, a widespread outbreak of tornadoes is unlikely.
Scattered showers are possible statewide on Wednesday, along with a couple of strong storms in the Pee Dee and Grand Strand areas. Conditions are expected to dry out on Thursday as Ida moves off the Mid Atlantic and New England coastline.
Original story from 10am Monday:
Ida is expected to pass west of the state on Tuesday with some impact, but likely less severe than what the state experienced with Fred some two weeks ago.
The category 4 hurricane made landfall at Port Fourchon, Louisiana, about 50 miles south of New Orleans, shortly before noon local time on Sunday. Ida is moving through interior Mississippi as a tropical storm Monday morning and is expected to weaken into a tropical depression later Monday.
The center is forecast to pass over the Tennessee Valley on Wednesday and into the mountains of West Virginia on Thursday. Southerly winds to the east of the circulation will transport moisture back into the state, especially over the Upstate, where locally heavy rain is possible starting Tuesday afternoon.
Rainfall amounts of 1 to 3 inches are most probable over the Upstate, especially from I-85 and west. These amounts, along with locally higher totals, may result in areas of flash flooding. The greatest risk of flash flooding is near the Escarpment, closer to the border of Georgia and North Carolina.
Strong wind shear is likely over the Upstate area. This shear may cause a few cells within the feeder bands to rotate; however, the air is not expected to be quite as unstable what the area saw with Fred. Brief, isolated tornadoes are still possible Tuesday afternoon and evening, but the most likely scenario favors less of a tornado risk with Ida.
Additional rain is likely Tuesday night into Wednesday over much of the state. Drier air will funnel in from the northwest Thursday and Friday once Ida moves off the Mid Atlantic and New England coasts. Lower humidity and more pleasant conditions are expected statewide toward the end of the week.
Tropical Storm Julian dissipated over the North Atlantic well east of Bermuda early Monday morning. There are three other areas forecasters are monitoring: Tropical Depression 10 strengthened to Tropical Storm Kate Monday morning, about 750 miles east-northeastward of the Leeward Islands. A strong tropical wave is likely to become the season's next tropical depression later this week over the open tropical Atlantic. Finally, another area of low pressure is likely to form in the southwest Caribbean, which has a low chance of becoming a depression late this week according to the Monday morning forecast from the National Hurricane Center. At this time, these other three systems are not expected to be a threat to South Carolina through the upcoming weekend.