Key Points:
- Tropical Depression Three has strengthened and is now Tropical Storm Chantal with 40 mph maximum sustained winds.
- A Tropical Storm Warning is in effect from the South Santee River to Surf City, NC. A Tropical Storm Watch remains in effect for Edisto Beach to South Santee River.
- Tropical storm force winds will arrive along the upper Charleston, Georgetown and Horry County coasts this evening starting around 8 p.m.
- The forecast track has shifted to the right since last night and now predicts landfall to occur near the mouth of the South Santee River around 8 a.m. Sunday.
- The intensity forecast has been increased slightly, and the National Hurricane Center's forecast calls for Chantal to have 50 mph sustained winds at landfall. The margin of error decreases as we approach landfall, but the error cone still encompasses the area from Charleston northeastward along our coast for the landfall point.
- The intensity at landfall could be about 10 mph weaker or stronger, based on the NHC's verification figures from recent years.
- A storm surge of 1-3 feet will affect most of South Carolina's coast. There can be minor coastal flooding with this afternoon's high tide (around 5 p.m.) along the Charleston, Georgetown, and Horry County coasts. There is a chance for minor coastal flooding with the early Sunday (around 4 a.m.) high tide along the Georgetown and Horry County coast.
- The rainfall forecast has changed to reflect the potential for heavier rainfall. The heaviest rain will fall near and to the right of where Chantal's center makes landfall. Widespread rainfall totals of 2-4 inches will occur primarily in the Pee Dee region, with locally heavier amounts of around 6 inches. Rainfall of one inch or more is in the forecast over the upper part of the Lowcountry and eastern Midlands. The rain will cause localized flooding, with the highest flood potential in Horry, Georgetown, Marion, and Dillon Counties.
- Isolated tornadoes may occur through this evening along and near the Grand Strand.
To nobody's surprise, we now have Tropical Storm Chantal spinning about 150 miles offshore of the Palmetto State.
Visible satellite imagery shows Chantal spinning about 140 miles southeast of Charleston.
Image Source: University of Wisconsin RealEarth
Weather radar shows bands of rain already affecting our Coastal Plain.
The latest forecast track from 11 a.m. indicates a track to bring significant impacts to the Grand Strand tonight and Sunday morning.
Here's the National Weather Service's forecast for rainfall through Sunday evening:
Here is the Excessive Rainfall Outlook map from the Weather Prediction Center. Flooding from the heavy rainfall is expected to be isolated in nature, with the best chance of flooding rain occurring over Horry County and northern Georgetown County.
Here's the storm surge forecast:
The Storm Prediction Center's Day 1 Severe Weather Outlook for South Carolina shows the area at risk for isolated tornadoes (zero to a few may occur) through tonight:
The tornado threat will continue into the early morning hours of Sunday, so you'll want to have multiple methods to receive tornado warnings (such as a properly configured mobile device alerts and a weather radio) set up before you go to bed tonight, and you should have a sheltering plan ready in the event you receive a warning. You may not have to decide how to react to a tornado warning, especially if it comes at 2:30 a.m. when you're half asleep.
The wind and rain forecast has been beefed up somewhat, but this remains a relatively minor event for us. Prep time is short now, but you have time to ensure you have what you need before conditions along our coast become unsuitable for being out as nightfall approaches. If you need prep advice, visit hurricane.sc.
In other news:
It's going to be hot next week, y'all. Tuesday and Wednesday will feature highs well into the 90s across South Carolina, with temperatures approaching 100 in the usual hot spots near I-20. Heat index readings over 105 are possible those days, and few places will see cooling afternoon thunderstorms. The heat will ease later next week to more typical midsummer readings as the afternoon thunderstorm coverage increases again.