Quick answer
When should you clean gutters in Charleston? Twice a year works for most Lowcountry homes: in late spring, after the live oaks finish dropping their old leaves and before the summer storms, and again in late fall once the pine straw is down. That timing matters because NOAA’s normals put close to half of Charleston’s 52.51 inches of yearly rain in June through September, which also falls inside hurricane season. For a free written estimate call (843) 867-2267 or get a free quote.
The rain calendar
Half of Charleston’s rain falls in four months
Charleston does not have a rainy winter like a lot of the country. The heavy months are summer, and the gutters need to be clear before they start.
NOAA’s 1991 to 2020 climate normals for Charleston International Airport put the yearly average at 52.51 inches of rain. June brings 6.21 inches, July 6.60, August 6.97 and September 6.01. Those four months add up to 25.79 inches, close to half of the year.
The rest of the year is far gentler. November is the driest month at 2.66 inches, and most months outside summer bring about 3 to 3.4 inches, with October a little wetter at 4.33.
Summer also overlaps the Atlantic hurricane season, which the National Hurricane Center runs from June 1 to November 30. A tropical system can drop more rain in a day than a normal month.
Source: NOAA National Centers for Environmental Information, 1991 to 2020 monthly normals for Charleston International Airport.
The leaf calendar
What clogs Lowcountry gutters, and when
Lowcountry trees do not all drop at once. Live oaks, pines and the hardwoods each have their own season, which is why one cleaning a year rarely keeps up.
| What falls | When | What it does in a gutter |
|---|---|---|
| Live oak leaves and tassels | Spring, as the new leaves come in | Small, stiff leaves pack into outlets and downspout elbows |
| Pine straw | Fall into early winter | Needles mat across the trough and dam the water behind them |
| Hardwood leaves | Late fall | Broad leaves cover outlets and hold wet debris against the gutter |
| Palmetto fronds and seed | Through the year | Heavy debris that lands in the gutter during storms |
Live oaks are the one that surprises newcomers. They hold their leaves through winter and drop the old ones in a rush each spring as the new growth pushes out. That puts a fresh load in the gutters just weeks before the wet season starts.
Spanish moss and roof debris
Moss, small twigs and roof grit also wash into gutters with every storm. On their own they are minor, but mixed with leaves they form the dense mat that stops a downspout cold.
Summer storms
How hard it rains on a Lowcountry roof
A clogged gutter can get through a drizzle. It cannot get through a Lowcountry thunderstorm, and NOAA publishes how hard those storms fall.
NOAA Atlas 14 is the federal reference for rainfall intensity. Pulled from the NOAA Precipitation Frequency Data Server for our Mount Pleasant location, it puts the hardest hour you should expect in a typical year at 1.74 inches. The hardest five minutes in a typical year fall at about 6.11 inches an hour.
To turn that into water at a downspout, multiply the roof area draining to it by the rainfall rate in inches per hour, then by 0.0104. The answer is gallons per minute.
| Rain in Mount Pleasant | Rate | 600 sq ft of roof to one downspout | 1,200 sq ft of roof to one downspout |
|---|---|---|---|
| Hardest hour in a typical year | 1.74 in/hr | About 11 gal/min | About 22 gal/min |
| Hardest 5 minutes in a typical year | 6.11 in/hr | About 38 gal/min | About 76 gal/min |
| Hardest hour in a 10 year storm | 2.95 in/hr | About 18 gal/min | About 37 gal/min |
| Hardest 5 minutes in a 100 year storm | 12.4 in/hr | About 77 gal/min | About 155 gal/min |
That is the reason 6 inch gutters are our standard on Lowcountry homes. Even a 6 inch gutter can only move water as fast as its outlets, so a single packed downspout turns a summer storm into a waterfall over the front edge.
Source: NOAA Atlas 14, Volume 2, precipitation frequency estimates for our Mount Pleasant location, pulled October 2026. Roof areas are round examples.
The plan
A gutter cleaning calendar for Charleston homes
Put the two calendars together and the timing is simple: clear the spring leaves before summer, and clear the fall straw before the year turns.
- Late April or May.Once the live oaks finish dropping, clean the gutters and flush every downspout before June storms start.
- Before a named storm.If a tropical system is in the forecast, a quick check of the outlets and downspouts is the cheapest storm prep you can do.
- After a big storm.Walk the house and look for gutters pulled off the fascia, seams dripping and downspouts knocked loose.
- Late fall.When the pine straw and hardwood leaves are down, clean again so the system is ready for spring.
- Gutters cleaned after live oak drop and again after pine straw season.
- Every downspout flushes clear from top to bottom.
- Downspouts end away from the foundation, and on raised homes, away from the space under the house.
- No water standing in the gutter a day after the rain.
Homes under heavy live oak and pine cover are good candidates for BroGuard gutter guards, which keep leaves and straw out of the trough. For raised and island homes, our coastal and raised home gutters page covers metals for the salt air and where the water should go. We clean and flush gutters across Mount Pleasant, James Island, West Ashley, Daniel Island and Summerville.
Want your gutters clear before storm season? Call (843) 867-2267
Get a Free QuoteLocal tip: after the live oaks drop in spring, check the downspout elbows at ground level. Live oak leaves are small enough to slide down the downspout and pack into the bottom bend.
Frequently Asked Questions
At least twice a year for most Lowcountry homes: once in late spring after the live oaks drop and once in late fall after the pine straw is down. Homes under heavy tree cover may need more often, or gutter guards.
Summer. NOAA’s normals put June through September at 25.79 inches at Charleston International Airport, close to half of the 52.51 inches the city gets in a year. August is the wettest month at 6.97 inches.
In spring. Live oaks keep their leaves through winter and shed the old ones as the new leaves come in, which puts a fresh load in the gutters just before the summer storms.
Yes, if you can do it safely before the storm arrives. Clear outlets and downspouts let the gutters carry tropical rain away from the house instead of spilling it against the walls and foundation.
A fine stainless mesh guard like BroGuard keeps live oak leaves and pine straw out of the trough. Light debris can sit on top and usually washes or blows off, so the gutter keeps draining.
Free estimates
Want your gutters ready before storm season?
Book a free written estimate with our local crew. We will clean the gutters, flush every downspout and show you anything that needs repair, before you spend anything.
The Brothers That Just Do Gutters · Charleston · (843) 867-2267 · Veteran owned and operated in Mount Pleasant, serving the Lowcountry