Hot and humid conditions are on the horizon for South Carolina’s Upstate, with temperatures expected to skyrocket starting early next week. A dangerous heat wave will settle over the region, pushing highs into the upper 90s Fahrenheit (35–37 °C) and beyond, particularly in areas east of the Appalachian Mountains.
How hot will it get in South Carolina next week?
By Tuesday, forecasts from the National Weather Service in Greenville-Spartanburg (GSP) anticipate temperatures soaring to 99°F (37.2°C) across the Upstate, with the heat intensifying further due to high humidity. This will drive heat index values — the “feels like” temperature — into the upper 90s and low 100s (37–39 °C) range. Tuesday and Wednesday are likely to be the most dangerous days, with some areas potentially reaching Heat Advisory criteria.
This oppressive heat will be widespread, impacting not just South Carolina, but also northeast Georgia, the North Carolina Piedmont, the Foothills, and portions of the North Carolina mountains.
What is a heat wave, and why does it matter?
According to the National Weather Service, a heat wave is defined as a prolonged period of abnormally high temperatures, usually lasting more than two days, and sometimes occurring with high humidity. These events can span large geographical areas, placing millions at risk for heat-related illnesses such as heat exhaustion and heat stroke.
Official weather outlook warns of dangerous conditions
The latest hazardous weather outlook warns residents that:
“A heatwave will develop next week bringing hot and humid conditions. Highs each afternoon will climb into the mid to upper 90s with heat indices ranging from the upper 90s to lower 100s. Locations east of the mountains could see heat indices approach or reach Heat Advisory Criteria on Tuesday afternoon and Wednesday afternoon.“
7-day forecast for Greenville-Spartanburg area
Friday afternoon will be sunny, with highs near 90°F (32.2°C) and light east-southeast winds. The night will be mostly clear with lows around 70°F (21.1°C).
Saturday will see the mercury rise to 92°F (33.3°C) under clear skies, followed by a mild night with lows near 71°F (21.7°C).
Sunday temperatures will peak around 94°F (34.4°C) with continued sunny conditions and light winds, dipping to 73°F (22.8°C) overnight.
By Monday, conditions will turn hot and intense, with highs near 97°F (36.1°C), setting the stage for Tuesday’s peak of 99°F (37.2°C). Nights remain clear and warm, with low 70s°F (21–23 °C) expected through Wednesday.
Wednesday and Thursday will both see blazing sun and highs again near 97°F (36.1°C), with humidity remaining elevated, making the heat feel even more stifling.
Outlook for heat-related health concerns
Doug Outlaw, meteorologist with the National Weather Service at GSP, emphasizes the importance of hydration and cool environments during this heat episode:
“Certainly keep hydrated. Drink water and make sure you’ve got some water available to drink if you’re going to be outside in the heat, and if at all possible, take breaks and come into an air conditioned building for a time to cool off.“
He also underscores the critical need to check on older adults, those with health issues, and pets, who are especially vulnerable to high heat. Never leave children or animals in parked cars, even for short periods, as temperatures can rise quickly to lethal levels.
Loose-fitting, breathable clothing is recommended to help the body cope with the excessive heat.
