For 9/17/2025
[ The forecast is updated daily by 3:30 pm EDT. ]
On Tuesday afternoon, all forecast zones across South Carolina are nearing peaks within the upper reaches of code GREEN for ground-level ozone. High pressure begins to build into the state on Wednesday with dry conditions and mostly sunny skies expected. Winds should remain rather light and variable turning westerly throughout the day tomorrow, which could help contribute to rising ozone readings as pollutants will not disperse much during the day. With the air mass beginning to age, ozone readings should once again near or exceed the green/yellow threshold. The Midlands, Central Savannah River Area, and Charleston Tri-County zones are forecast to see ground-level ozone averages in code YELLOW on Wednesday with the Upstate, Pee Dee, and Catawba zones forecast to see code GREEN.
| County * |
Color Code |
AQI |
| Abbeville |
Good (Green) |
50 |
| Aiken |
Moderate (Yellow) |
54 |
| Anderson |
Good (Green) |
50 |
| Barnwell |
Moderate (Yellow) |
54 |
| Berkeley |
Moderate (Yellow) |
51 |
| Calhoun |
Moderate (Yellow) |
51 |
| Charleston |
Moderate (Yellow) |
51 |
| Cherokee |
Good (Green) |
50 |
| Chester |
Good (Green) |
48 |
| Chesterfield |
Good (Green) |
49 |
| Darlington |
Good (Green) |
49 |
| Dillon |
Good (Green) |
49 |
| Dorchester |
Moderate (Yellow) |
51 |
| Edgefield |
Moderate (Yellow) |
54 |
| Fairfield |
Moderate (Yellow) |
51 |
| Florence |
Good (Green) |
49 |
| Greenville |
Good (Green) |
50 |
| Greenwood |
Good (Green) |
50 |
| Kershaw |
Moderate (Yellow) |
51 |
| Lancaster |
Good (Green) |
48 |
| Laurens |
Good (Green) |
50 |
| Lee |
Good (Green) |
49 |
| Lexington |
Moderate (Yellow) |
51 |
| Marlboro |
Good (Green) |
49 |
| McCormick |
Moderate (Yellow) |
54 |
| Newberry |
Moderate (Yellow) |
51 |
| Oconee |
Good (Green) |
50 |
| Pickens |
Good (Green) |
50 |
| Richland |
Moderate (Yellow) |
51 |
| Saluda |
Moderate (Yellow) |
51 |
| Spartanburg |
Good (Green) |
50 |
| Sumter |
Moderate (Yellow) |
51 |
| Union |
Good (Green) |
50 |
| York |
Good (Green) |
48 |
| GA-Columbia |
Moderate (Yellow) |
54 |
| GA-Richmond |
Moderate (Yellow) |
54 |
| * Ozone forecasts are not issued for counties not listed in this table.
|
| AQI Color Code (Value) |
Cautionary Statement |
|
Good
(0-50)
|
No health effects are expected.
|
|
Moderate
(51-100)
|
Unusually sensitive people should consider limiting prolonged outdoor exertion.
|
|
Unhealthy for Sensitive Groups
(101-150)
|
The following groups should limit prolonged outdoor exertion:
- People with lung disease, such as asthma
- Children and older adults
- People who are active outdoors
|
|
Unhealthy
(151-200)
|
The following groups should avoid prolonged outdoor exertion:
- People with lung disease, such as asthma
- Children and older adults
- People who are active outdoors
Everyone else should limit prolonged outdoor exertion.
|
|
Very Unhealthy
(200+)
|
The following groups should avoid all outdoor exertion:
- People with lung disease, such as asthma
- Children and older adults
- People who are active outdoors
Everyone else should limit outdoor exertion.
|
