South Carolina weather and outdoor projects
South Carolina has hot, humid summers and mild winters. Columbia in the Midlands is one of the hottest cities in the Southeast in summer, while Charleston on the coast is humid, rainy in summer and exposed to hurricanes.
Fall and spring are the best seasons for staining, painting and sealing. Summer afternoons often bring storms, and nights stay humid, so start early and finish by mid-afternoon. Freezes happen a few times most winters inland but are less common on the coast. Pollen in spring can stick to wet finishes.
Frost dates in South Carolina
In Columbia, the median last spring freeze (32°F) is around March 25 and the median first fall freeze is around November 7, a frost-free season of about 229 days.
In Charleston, the median last spring freeze (32°F) is around March 7 and the median first fall freeze is around November 27, a frost-free season of about 266 days.
Frost dates matter for concrete, which must not freeze in its first 48 hours, for paint and caulk that need nights above their minimum, and for lawn care, since crabgrass preventer goes down as the soil warms in spring. See how late in fall you can stain, paint or seal.
Best time to stain a deck in South Carolina
In Columbia, the most reliable months are April–May and September–October. March, June, August and November can also work on the right days. In December–February, nights average about 36°F, too cold for the coating to dry and cure overnight. July is hot, with average highs near 93°F and about 24 days a month at 90°F or more, so work early in the day. In March and November, nights average about 43°F, so finish early on mild days and check the overnight low. June and August are hot, with highs near 90°F, so start early and keep out of full afternoon sun.
In Charleston, the most reliable months are April–May and September–October. June–August and November–March can also work on the right days. January is cool, with highs around 60°F, so choose the warmest afternoons. In February–March and November–December, nights average about 44°F, so finish early on mild days and check the overnight low. June–August is hot, with highs near 90°F, so start early and keep out of full afternoon sun.
Check this week’s hour-by-hour verdict with the deck staining forecast.
Best time to paint outside in South Carolina
In Columbia, the most reliable months are April–May and September–October. June, August and November–March can also work on the right days. July is hot, with average highs near 93°F and about 24 days a month at 90°F or more, so work early in the day. January is cool, with highs around 57°F, so choose the warmest afternoons. In February–March and November–December, nights average about 40°F, so finish early on mild days and check the overnight low. June and August are hot, with highs near 90°F, so start early and keep out of full afternoon sun.
In Charleston, the most reliable months are March–May and September–November. June–August and December–February can also work on the right days. In December–February, nights average about 41°F, so finish early on mild days and check the overnight low. June–August is hot, with highs near 90°F, so start early and keep out of full afternoon sun.
Check this week’s hour-by-hour verdict with the exterior painting forecast.
Best time to pour concrete in South Carolina
In Columbia, the most reliable months are April–October. March and November can also work on the right days. December–February averages about 12 nights a month at or below 32°F, so fresh concrete needs blankets or heated enclosures. March and November bring about 5 freezing nights a month, so pick a mild spell and keep curing blankets on hand.
In Charleston, the most reliable months are April–November. February–March and December can also work on the right days. January averages about 9 nights a month at or below 32°F, so fresh concrete needs blankets or heated enclosures. February–March and December bring about 4 freezing nights a month, so pick a mild spell and keep curing blankets on hand.
Check this week’s hour-by-hour verdict with the concrete pouring forecast.
Best time to seal a driveway in South Carolina
In Columbia, the most reliable months are May–October. March–April can also work on the right days. December–January is too cold, with average highs around 58°F. In February and November, nights average about 39°F, too cold for the coating to dry and cure overnight. In March–April, nights average about 48°F, so finish early on mild days and check the overnight low.
In Charleston, the most reliable months are April–May and September–October. March, June–August and November can also work on the right days. In December–February, nights average about 41°F, too cold for the coating to dry and cure overnight. In March and November, nights average about 47°F, so finish early on mild days and check the overnight low. June–August averages about 9 wet days a month, so wait for a clear stretch.
Check this week’s hour-by-hour verdict with the driveway sealing forecast.
Best time to fertilize or treat a lawn in South Carolina
In Columbia, the most reliable months are February–May and September–November. June, August and December–January can also work on the right days. July is hot, with average highs near 93°F and about 24 days a month at 90°F or more, so work early in the day. December–January is cool, with highs around 58°F, so choose the warmest afternoons. June and August are hot, with highs near 90°F, so start early and keep out of full afternoon sun.
In Charleston, the most reliable months are September–May. June–August can also work on the right days. June–August is hot, with highs near 90°F, so start early and keep out of full afternoon sun.
Check this week’s hour-by-hour verdict with the lawn fertilizer forecast.
How the weather differs across South Carolina
| Place | Hottest month avg high | Coldest month avg low | Rain per year | Last spring freeze | First fall freeze |
|---|---|---|---|---|---|
| Columbia | 93°F | 35°F | 45 in | March 25 | November 7 |
| Charleston | 91°F | 39°F | 53 in | March 7 | November 27 |
Of the places above, Charleston has the most good months for staining, painting and concrete combined (18 job-months), and Columbia has the fewest (15). If you live between them, expect something in between, and higher ground to be cooler with a shorter season.
Monthly weather in Columbia
| Month | Avg high | Avg low | Wet days* | Rain | 3 PM humidity | Freezing nights |
|---|---|---|---|---|---|---|
| January | 57°F | 35°F | 6 | 3.5 in | 43% | 14 |
| February | 61°F | 37°F | 6 | 3.4 in | 41% | 9 |
| March | 68°F | 44°F | 6 | 3.6 in | 37% | 4 |
| April | 77°F | 52°F | 5 | 2.8 in | 38% | 1 |
| May | 84°F | 61°F | 5 | 3.5 in | 42% | 0 |
| June | 90°F | 69°F | 7 | 5.0 in | 47% | 0 |
| July | 93°F | 72°F | 7 | 5.3 in | 49% | 0 |
| August | 91°F | 71°F | 7 | 4.7 in | 50% | 0 |
| September | 86°F | 65°F | 5 | 3.9 in | 48% | 0 |
| October | 77°F | 53°F | 4 | 3.1 in | 46% | 1 |
| November | 66°F | 42°F | 5 | 2.8 in | 43% | 6 |
| December | 59°F | 37°F | 6 | 3.7 in | 46% | 12 |
*Days with at least 0.1 inch of rain or melted snow. Freezing nights: average nights a month at or below 32°F. Humidity is calculated from NOAA hourly normal temperature and dew point at 3 PM.
Monthly weather in Charleston
| Month | Avg high | Avg low | Wet days* | Rain | 3 PM humidity | Freezing nights |
|---|---|---|---|---|---|---|
| January | 60°F | 39°F | 6 | 3.4 in | 47% | 9 |
| February | 64°F | 42°F | 5 | 3.0 in | 45% | 4 |
| March | 70°F | 47°F | 5 | 3.4 in | 43% | 2 |
| April | 77°F | 55°F | 5 | 3.3 in | 45% | 0 |
| May | 84°F | 63°F | 5 | 3.3 in | 51% | 0 |
| June | 89°F | 70°F | 8 | 6.2 in | 58% | 0 |
| July | 91°F | 74°F | 9 | 6.6 in | 60% | 0 |
| August | 90°F | 73°F | 9 | 7.0 in | 62% | 0 |
| September | 85°F | 68°F | 7 | 6.0 in | 60% | 0 |
| October | 78°F | 58°F | 5 | 4.3 in | 53% | 0 |
| November | 69°F | 47°F | 4 | 2.7 in | 50% | 1 |
| December | 63°F | 42°F | 6 | 3.4 in | 51% | 6 |
Use the averages, then check the forecast
These ratings describe a typical month, not a particular week. A warm spell in a “poor” month can give you a good day, and a wet week can spoil a “good” one. Use this page to plan the season, then check the 7-day forecast for your ZIP code before you buy materials or book help. Each project forecast checks the hours after you finish too: overnight lows, dew and rain that would ruin fresh stain, paint, sealer or concrete.
About this data
Monthly temperatures, rain days, snowfall and freeze dates are NOAA National Centers for Environmental Information (NCEI) U.S. Climate Normals for 1991–2020 at COLUMBIA, CHARLESTON INTL AP. Ratings apply the same temperature limits as our forecasts (for example, 50°F or warmer for deck stain and driveway sealer, and no freezing nights for new concrete) to the average month. Your product label always takes priority.
Frequently asked questions
When is the best time to stain a deck in South Carolina?
In Columbia, April–May and September–October. In Charleston, April–May and September–October. Look for at least 24 dry hours before and after, and nights above about 40°F. The deck staining forecast checks your exact week.
When is the last frost in South Carolina?
Columbia: around March 25; Charleston: around March 7. These are median dates from NOAA 1991–2020 normals, so a freeze after them happens in about half of years. Low spots and valleys freeze later in spring.
Can you pour concrete in winter in South Carolina?
Yes, but it needs cold-weather practices. Columbia averages about 35 freezing nights from December to February, so fresh concrete needs insulated blankets, a heated enclosure or an accelerated mix, and must not freeze in the first 48 hours. Many homeowners wait for spring.
What months are best for sealing a driveway in South Carolina?
In Columbia, May–October. In Charleston, April–May and September–October. Most sealers need 50°F or warmer for 24 hours and a dry day after. See the driveway sealing forecast.