Overland Park › Guides › Gutter calendar
Most gutter-cleaning advice is written for somewhere else. "Clean in spring and fall" assumes one leaf drop in October and nothing much in April. Johnson County has two debris seasons, a hail season in between, and a dominant street tree that refuses to drop its leaves until January. This calendar is built around what actually lands in a gutter here, and when.
Why a Kansas City calendar is different
Three local facts drive everything below. First, the rain: Overland Park's climate normals put annual precipitation at 40.17 inches, about a third above the national figure, with May the wettest month at 5.8 inches across fourteen rainy days and individual storms of 2.5 to 4 inches routine enough that contractors size gutters around them. Second, the storms: the Kansas City area averages 40 to 60 thunderstorm days a year, with hail season running March through June. Third, the trees. K-State Research and Extension's Johnson County office publishes a recommended-trees list whose "not recommended" and "use with caution" sections read like a manifest of what fills local gutters — silver maple, cottonwood, sweetgum, and the pin oak that was the default shade tree in every subdivision built between 1955 and 1985.
The pin oak is the reason the county's cleaning schedule breaks the national rule. Pin oaks are marcescent: they hold their dead leaves through the first freezes and let them go a few at a time from late October into January, sometimes February. A gutter cleaned in early November under a pin oak is packed again by Christmas. The single most useful thing this calendar says is that the main fall cleaning in Johnson County happens in late December.
The year at a glance
| Month | Precipitation (normal) | What's falling | Weather risk | What to do |
|---|---|---|---|---|
| January | 0.9" | Pin oak leaves (still), sweetgum balls, ice | Freeze-thaw; ice load on north runs | Final winter cleaning if December was skipped; check for sagging runs after ice |
| February | 1.3" | Last pin oak leaves, sweetgum balls | Freeze-thaw continues | Book spring work — contractors fill up by March |
| March | 2.4" | Twigs and winter debris | Hail season opens; first severe storms | Walk the perimeter after the first storm; note dents and pulled hangers |
| April | 3.9" | Pin oak and red oak catkins (mid-month on) | Severe storms increase; hail | Do not clean yet — catkins are still falling |
| May | 5.8" | Catkins finish; silver and red maple helicopters; elm seed | Wettest month; peak hail; 14 rainy days | Watch inside corners for overflow — the sizing test |
| June | 5.1" | Cottonwood fluff; late helicopters | Downbursts; heavy rain | FIRST CLEANING — early June, after helicopters and cottonwood |
| July | 4.3" | Little debris; mosquito season in standing water | Afternoon storms | Check for standing water (pitch) and downspout discharge |
| August | 4.0" | Little debris; early hackberry | Storms; heat | Quiet month — good time for replacement quotes |
| September | 4.5" | First sycamore and ash leaves; twigs from wind | Wind events | Schedule fall cleaning; book installs before winter |
| October | 3.3" | Sycamore, maple, hackberry; first pin oak drop late in month | Cooling; first frost late | Under heavy canopy: SECOND CLEANING late October |
| November | 2.2" | Main oak drop begins in earnest; sweetgum balls start | First freezes | Most of the metro cleans now — in Johnson County it is too early |
| December | 1.6" | Pin oak drop continues; sweetgum balls | Snow begins (17" annual); freeze-thaw | MAIN CLEANING — late December or early January, after the pin oaks let go |
Monthly precipitation figures are rounded normals for the Overland Park area; the NWS Kansas City office publishes the underlying data. Debris timing shifts a week or two with the spring — a warm March pulls the catkins earlier.
January–February: ice, sweetgum balls, and oak leaves that never fell
The driest stretch of the year is not the quietest for gutters. Whatever the pin oaks held through December comes down in January, sweetgum balls — the spiked, golf-ball-sized seed pods that K-State singles out as a reason not to plant the tree — roll off roofs and jam downspout outlets, and the freeze-thaw cycle that runs from December through February puts real weight on north-facing runs. A 40-foot gutter full of slush weighs several hundred pounds, which is what pulls spiked hangers out of 1960s fascia and loosens hidden hangers set too far apart on newer homes.
If the December cleaning was done, January is a walk-around month: look for runs that have visibly sagged since fall, downspouts that have separated from the wall, and icicles forming along the front lip, which mean water is standing in the gutter rather than draining. If December was skipped, a January cleaning on a day above freezing is the right correction. February is the month to book spring installation work; by March, contractors' schedules fill with hail calls.
March–April: hail season opens, catkins begin
March brings the first severe storms of the year and the first hail. The National Weather Service classifies a storm as severe at three-quarter-inch hail or 58-mile-an-hour winds, and Johnson County sees several such days most springs. The routine after any storm with hail is the same: a ground-level walk of the house, looking at west- and south-facing gutter runs for dimpling, at drip edges for crushing, and at downspouts for creasing, and a dated photo of anything found. The hail damage guide covers what matters for a claim.
By mid-April the pin oaks and red oaks are dropping catkins — the stringy, yellow-green flower tassels that arrive in enormous quantity for about three weeks — and this is the month homeowners most often clean too early. Catkins mat over any gutter opening and pass straight through perforated guards; a gutter cleaned in mid-April is full again by May. The right response in April is patience and, on a two-story, a look at the inside corners during the first big storm to see whether they overflow. That overflow is the sizing test: a corner that sheets in an April rain is telling the homeowner the gutter is 5-inch on a roof that needed 6-inch.
May: the wettest month and helicopter season
May is the hinge of the year. It is the wettest month at 5.8 inches, the peak of hail season, and the month the maples finish what the oaks started: silver and red maple samaras — helicopters — spin down through the second half of the month and lodge in whatever catkins are already in the gutter. The combination has roughly the density of wet felt. Elm seed adds to it in neighborhoods with surviving American or Siberian elms.
A gutter that is 40 percent full of catkins and helicopters has the capacity of a 3-inch gutter, and May's storms are the ones that find it. Overflow in May is not always a sizing problem; often it is a cleaning that hasn't happened yet. The first cleaning of the year should wait for the helicopters to finish, which means the last few days of May at the earliest and early June for most of the county.
June–August: cottonwood fluff, downbursts, and the quiet months
Early June is the first cleaning. It should clear catkins, helicopters, and whatever winter debris was missed, and it should include a check of pitch — water standing in a gutter in June breeds mosquitoes through the summer — and of every downspout's discharge point. Cottonwood fluff arrives in the same window along the creek corridors, particularly Little Mill Creek in Lenexa and the Mill Creek streamway through Shawnee; it mats over perforated guards and reverse-curve covers and is the one debris type only micro-mesh handles reliably.
July and August are the quiet months for debris and the active ones for weather. Afternoon storms and occasional downbursts test the system a cleaning just cleared, and a gutter that overflows at the same corner in July that it overflowed in April is now a confirmed sizing problem rather than a maintenance one. August is, for the same reason, a good month to get replacement quotes — contractors are between the spring hail rush and the fall installation season, and estimates come faster.
September–October: sycamore, ash, and the first oak drop
The fall season starts gently. Sycamores and the surviving ashes — emerald ash borer has taken most of the county's — drop first in September, along with twigs from the wind events that come with the season change. October brings the maples, hackberries, and sycamores in earnest, and in the last week of the month the pin oaks begin. For most Johnson County homes, October is a watching month. Under heavy canopy — Prairie Village, north Overland Park, the older streets of Leawood and Shawnee — it is the second cleaning of the year, in the last week of the month, to clear the early drop before the oaks bury it.
September and early October are also the last comfortable window to schedule an installation before winter. Aluminum can be installed in any month, but sealant needs a few hours above about 40°F to cure, and from December on, installs are scheduled around the forecast.
November–December: the main event
November is when the rest of the country cleans its gutters, and in Johnson County it is too early. The main oak drop begins in earnest in November and continues through December; a cleaning done the week before Thanksgiving under a pin oak catches perhaps half the season. Sweetgum balls begin falling in the same window and continue through February, jamming downspout outlets as they go.
The main cleaning of the year — the one that decides whether the gutters work through winter — belongs in late December or the first days of January, after the pin oaks have finally let go. It is not a pleasant time to be on a ladder, which is the strongest argument for paying someone: single-story cleaning runs $70 to $200 in the Kansas City market and two-story $120 to $290. It is also the month when micro-mesh guards, which pass the whole season's debris over the top, earn their price under a mature canopy.
How often, really? A Johnson County answer
Twice a year — early June and late December — covers most homes. Three times — adding late October — under a mature oak and maple canopy. Once, in late December, can be enough for a new subdivision with young street trees and no creek nearby. And zero is not an option: the mosquito, fascia, and foundation problems that follow a neglected gutter cost more than any schedule above.
The printable checklist
Print this page (the site's print stylesheet drops the navigation and buttons) and keep the list on the garage wall.
- January — Walk the house after the first ice; look for sagging runs and separated downspouts. Clean if December was skipped.
- February — Book spring installation or replacement work before hail season fills schedules.
- March — After the first hail: ground-level inspection of west- and south-facing runs; dated photos of any damage.
- April — Do not clean. Watch inside corners during storms for overflow (the sizing test).
- May — Wait for the helicopters to finish. Note any corner that overflows again.
- Early June — FIRST CLEANING. Check pitch (no standing water) and downspout discharge (four to six feet from the foundation).
- July–August — Get replacement quotes if a corner overflowed in April and again in July. Contractors are between rushes.
- September — Schedule fall cleaning; last comfortable window to book an install before winter.
- Late October — Under heavy canopy: SECOND CLEANING. Elsewhere, watch.
- November — Resist the national habit. The oaks are not done.
- Late December / early January — MAIN CLEANING, after the pin oaks let go.
A cleaning or a replacement in any of these months starts with one call. Call (913) 444-6447 to reach independent Johnson County contractors who quote in writing.
Sources
- National Weather Service, Kansas City/Pleasant Hill — climate normals and annual precipitation records
- K-State Research and Extension, Johnson County — Recommended Landscape Trees for Metropolitan Kansas City (rev. 2022)
- Prepare Metro KC (Mid-America Regional Council) — severe thunderstorms in the Kansas City region