Much of the state is experiencing an extended stretch of above-normal temperatures as a ridge of high pressure builds across the eastern United States.
High temperatures through midweek are expected to reach the 90s across much of the state, except for along the immediate coastline where temperatures will max out in the 80s.
Columbia is forecast to reach 93 degrees on Tuesday and 94 degrees on Wednesday, while much of the Upstate is expected to top out near 90 degrees.
The temperatures will resemble summer-like conditions more commonly experienced in late-June rather than mid-May, although readings are expected to remain below record territory.
Sinking air associated with the expanding Bermuda ridge is expected to suppress thunderstorm activity through much of the week, allowing the UV Index to climb into the “very high” range.
A piece of good news is that humidity levels are not expected to become overly excessive, meaning that heat index values should remain close to the actual air temperature.
An air temperature of 90 degrees with a humidity value around 60% can make it feel like it is closer to 100 degrees, but conditions like that are not expected this week and usually do not appear until at least late June.
By Thursday, the ridge is expected to weaken, allowing a frontal boundary with increasing rain chances to push into the state.
The additional clouds and rainfall will allow temperatures to return closer to seasonal norms, or even slightly below average, by Friday and into the weekend.
Forecast models indicate rainfall totals associated with the front are expected to remain fairly light through the week, meaning many communities will still be searching for drought relief.
May is typically when many observation sites experience their first 90-degree temperatures of the year, but because of an unusually warm spring, many have already reached the 90 degrees in 2026.
During a typical year, Columbia averages roughly 75 days with temperatures at or above 90 degrees, making it one of the warmer locations in the state.
Many coastal communities usually experience about half that number because of the cooling effects from the Atlantic Ocean.
Because some residents may not yet be acclimated to the warmer weather, it is typically advised that people make sure to stay hydrated, wear lightweight clothing and limit outdoor activities during the hottest hours of the day.