Data source: National Weather Service (NWS) Last verified: July 17, 2026

Extreme Heat

Heat Advisory (ADVISORY) - expires July 17, 2026 at 8:00 PM EDT

Areas affected: Robeson; Bladen; Columbus; Inland Pender; Coastal Pender; Inland New Hanover; Coastal New Hanover; Inland Brunswick; Coastal Brunswick; Marlboro; Darlington; Dillon; Florence; Marion; Williamsburg; Coastal Horry; Inland Georgetown; Coastal Georgetown; Central Horry; Northern Horry

Heat Advisory issued July 17 at 2:20AM EDT until July 17 at 8:00PM EDT by NWS Wilmington NC

• WHAT...Heat index values up to 109 expected.

• WHERE...Portions of southeast North Carolina and northeast South Carolina.

• WHEN...From 11 AM this morning to 8 PM EDT this evening.

• IMPACTS...Hot temperatures and high humidity may cause heat illnesses.

What to do: Drink plenty of fluids, stay in an air-conditioned room, stay out of the sun, and check up on relatives and neighbors.

Source: NWS Wilmington NC

Heat Advisory (ADVISORY) - expires July 17, 2026 at 10:15 AM EDT

Areas affected: Inland Berkeley; Charleston; Tidal Berkeley

Heat Advisory issued July 17 at 2:08AM EDT until July 17 at 7:00PM EDT by NWS Charleston SC

• WHAT...Heat index values up to 110 expected.

• WHERE...Charleston, Inland Berkeley, and Tidal Berkeley Counties.

• WHEN...From 11 AM this morning to 7 PM EDT this evening.

• IMPACTS...Hot temperatures and high humidity may cause heat illnesses.

What to do: Drink plenty of fluids, stay in an air-conditioned room, stay out of the sun, and check up on relatives and neighbors.

Source: NWS Charleston SC

Air Quality

Air Quality Alert (ADVISORY) - expires July 17, 2026 at 8:00 PM EDT

Areas affected: York; Chester

Air Quality Alert issued July 17 at 12:45AM EDT by NWS Greenville-Spartanburg SC

The South Carolina Department of Environmental Services (SCDES) has issued a Code Orange Ground Level Ozone Action Day for the Catawba region of South Carolina, from 10 AM this morning to 8 PM EDT this evening.

Dominant high pressure will ensure minimal cloud cover and light and variable winds. Long-range wildfire smoke will also transport ozone precursors into the area. These factors will allow for sufficient ozone production, compounding with weak dispersion characteristics of an already pollutant-loaded atmosphere.

An ozone action day means that atmospheric conditions will likely produce unhealthy concentrations of ground level ozone air pollution. A Code Orange forecast indicates that ground level ozone concentrations are expected to be unhealthy for sensitive groups, which includes people with lung disease, older adults, and children. Sensitive groups should reduce prolonged or heavy outdoor exertion, take more breaks, and do less intense activities, especially during afternoon and early evening hours. You can help prevent ozone pollution by walking or riding your bicycle, taking your lunch to work, reducing idling, conserving energy, and keeping your vehicle properly tuned. For additional information, please visit the South Carolina Department of Environmental Services website at http://www.des.sc.gov/ozone or the Environmental Protection Agency AirNow website at https://www.airnow.gov.

Source: NWS Greenville-Spartanburg SC

Air Quality Alert (ADVISORY) - expires July 18, 2026 at 12:30 AM EDT

Areas affected: York; Chester

Air Quality Alert issued July 17 at 12:20AM EDT by NWS Greenville-Spartanburg SC

The South Carolina Department of Environmental Services (SCDES) has issued a Code Orange Ground Level Ozone Action Day for the Catawba region of South Carolina, from 10 AM this morning to 8 PM EDT this evening.

Dominant high pressure will ensure minimal cloud cover and light and variable winds. Long-range wildfire smoke will also transport ozone precursors into the area. These factors will allow for sufficient ozone production, compounding with weak dispersion characteristics of an already pollutant-loaded atmosphere.

An ozone action day means that atmospheric conditions will likely produce unhealthy concentrations of ground level ozone air pollution. A Code Orange forecast indicates that ground level ozone concentrations are expected to be unhealthy for sensitive groups, which includes people with lung disease, older adults, and children. Sensitive groups should reduce prolonged or heavy outdoor exertion, take more breaks, and do less intense activities, especially during afternoon and early evening hours. You can help prevent ozone pollution by walking or riding your bicycle, taking your lunch to work, reducing idling, conserving energy, and keeping your vehicle properly tuned. For additional information, please visit the South Carolina Department of Environmental Services website at http://www.des.sc.gov/ozone or the Environmental Protection Agency AirNow website at https://www.airnow.gov.

Source: NWS Greenville-Spartanburg SC

Air Quality Alert (ADVISORY) - expires July 17, 2026 at 8:00 PM EDT

Areas affected: York; Chester

Air Quality Alert issued July 16 at 8:06PM EDT by NWS Greenville-Spartanburg SC

The South Carolina Department of Environmental Services (SCDES) has issued a Code Orange Ground Level Ozone Action Day for the Catawba region of South Carolina, from 10 AM to 8 PM EDT Friday.

Dominant high pressure will ensure minimal cloud cover and light and variable winds. Long-range wildfire smoke will also transport ozone precursors into the area. These factors will allow for sufficient ozone production, compounding with weak dispersion characteristics of an already pollutant-loaded atmosphere.

An ozone action day means that atmospheric conditions will likely produce unhealthy concentrations of ground level ozone air pollution. A Code Orange forecast indicates that ground level ozone concentrations are expected to be unhealthy for sensitive groups, which includes people with lung disease, older adults, and children. Sensitive groups should reduce prolonged or heavy outdoor exertion, take more breaks, and do less intense activities, especially during afternoon and early evening hours. You can help prevent ozone pollution by walking or riding your bicycle, taking your lunch to work, reducing idling, conserving energy, and keeping your vehicle properly tuned. For additional information, please visit the South Carolina Department of Environmental Services website at http://www.des.sc.gov/ozone or the Environmental Protection Agency AirNow website at https://www.airnow.gov.

Source: NWS Greenville-Spartanburg SC

Air Quality Alert (ADVISORY) - expires July 17, 2026 at 8:00 PM EDT

Areas affected: York; Chester

Air Quality Alert issued July 16 at 8:02PM EDT by NWS Greenville-Spartanburg SC

The South Carolina Department of Environmental Services (SCDES) has issued a Code Orange Ground Level Ozone Action Day for the Catawba region of South Carolina, from 10 AM to 8 PM EDT Friday.

Dominant high pressure will ensure minimal cloud cover and light and variable winds. Long-range wildfire smoke will also transport ozone precursors into the area. These factors will allow for sufficient ozone production, compounding with weak dispersion characteristics of an already pollutant-loaded atmosphere.

An ozone action day means that atmospheric conditions will likely produce unhealthy concentrations of ground level ozone air pollution. A Code Orange forecast indicates that ground level ozone concentrations are expected to be unhealthy for sensitive groups, which includes people with lung disease, older adults, and children. Sensitive groups should reduce prolonged or heavy outdoor exertion, take more breaks, and do less intense activities, especially during afternoon and early evening hours. You can help prevent ozone pollution by walking or riding your bicycle, taking your lunch to work, reducing idling, conserving energy, and keeping your vehicle properly tuned. For additional information, please visit the South Carolina Department of Environmental Services website at http://www.des.sc.gov/ozone or the Environmental Protection Agency AirNow website at https://www.airnow.gov.

Source: NWS Greenville-Spartanburg SC

Air Quality Alert (ADVISORY) - expires July 17, 2026 at 8:00 PM EDT

Areas affected: Northern Lancaster; Southern Lancaster

Air Quality Alert issued July 16 at 3:32PM EDT by NWS Columbia SC

The South Carolina Department of Environmental Services has issued a Code Orange Ozone Action Day for the Catawba region of South Carolina.

An ozone action day means that atmospheric conditions will likely produce unhealthy concentrations of ground level ozone air pollution. A Code Orange forecast indicates that ground level ozone concentrations are expected to be unhealthy for sensitive groups, which includes people with lung disease, older adults, and children. Sensitive groups should reduce prolonged or heavy outdoor exertion, take more breaks, and do less intense activities, especially during afternoon and early evening hours. You can help prevent ozone pollution by walking or riding your bicycle, taking your lunch to work, reducing idling, conserving energy, and keeping your vehicle properly tuned. For additional information, please visit the South Carolina Department of Environmental Services ozone web site at http://www.des.sc.gov/ozone or the Environmental Protection Agency AirNow website at https://www.airnow.gov.

Source: NWS Columbia SC

Source

Alert data provided by the National Weather Service (NWS). This page shows active alerts only and is refreshed daily. For real-time updates, visit weather.gov.