How hot artificial turf gets in a Northern Colorado summer, and what actually cools it

01How much hotter than grass or concrete does artificial turf get?

Much hotter than grass, and hotter than paving too.

The broadest look is a 2024 systematic review of 23 studies in the International Journal of Biometeorology. Across those studies, synthetic grass surfaces measured 9.4 to 33.7°C hotter than natural grass, about 17 to 61°F (Singh et al., 2024). Penn State’s Center for Sports Surface Research puts the usual gap at 35 to 55°F, with grass commonly reading 75 to 95°F on a hot day and very rarely passing 100°F (Penn State).

The reason is water. Grass leaves release water vapor, and the evaporation keeps them below the air temperature. Plastic blades have nothing to evaporate, and Penn State names the fibers themselves, not only the infill, as a major source of the heat.

For paving, the clearest side-by-side numbers come from a 2002 Brigham Young University field report from Provo, Utah. It is not peer-reviewed, but Penn State cites it:

Source: Williams and Pulley, Brigham Young University (report).

Concrete and asphalt both ran cooler than the turf. The same report logged the study’s top reading, 200°F on a 98°F day, and Penn State calls it the highest synthetic turf temperature published in research; Penn State’s own measurements in central Pennsylvania have reached 175°F.

02How many turf-hot days does each Northern Colorado town get?

The hot afternoons are not spread evenly along the corridor. NOAA’s 1991–2020 normals, by the station nearest each town:

Source: NOAA NCEI U.S. Climate Normals 1991–2020 (five-station data).

The Weld County plains around Greeley get about twice as many 90°F days as Fort Collins, and the towns nearest the Longmont station are not far behind.

03Why does turf get so hot here, even when the air is mild?

Because sunlight heats turf more than warm air does. The BYU researchers found that light had a greater effect on turf temperature than the air did, and even in October their turf reached 112.4°F, 32.4°F above the air. Penn State lists what makes synthetic surfaces hottest:

• Sun and a clear sky.
• Low humidity.
• The hours from noon to 3 p.m.

Northern Colorado summers bring all of them. The Colorado Climate Center describes the plains as having “low relative humidity, abundant sunshine” (Colorado Climate Center). CoAgMET, the Climate Center’s network of research weather stations, shows how dry the hottest hours are:

• Greeley 4 station, June through August 2025: 135 hours averaged 90°F or hotter, and relative humidity in those hours averaged 16.6%, from 9.6% to 26.0% (CoAgMET, Greeley).
• Fort Collins station, on the CSU campus: 144 such hours, at an average 15.9% humidity, from 8.3% to 29.2% (CoAgMET, Fort Collins).

For comparison, Penn State ran its watering tests on days with 33 to 39% humidity (McNitt et al.). The same strong sun also fades turf over the years.

04What cools artificial turf down without buying anything?

Shade lasts; water doesn’t.

• Shade works for as long as it falls. In the BYU study, shaded turf averaged about 76°F between 9 a.m. and 2 p.m. and topped out at 99°F, under air that averaged 81°F. A 2022 study of playground surfaces, tabulated in the 2024 review, found synthetic grass averaging about 136°F in the sun and about 90°F in the shade, the same average as natural grass in the sun; the peaks were about 176°F and 108°F. A tree, a shade sail, a pergola or the house’s own shadow over the part of the yard people use keeps working all afternoon. If turf is still being planned, check where the shade falls at 3 p.m. before deciding where the turf goes.
• Timing. Plan play for the morning or the evening. Penn State’s hottest window is noon to 3 p.m., and it suggests mornings and evenings for practice on synthetic fields.
• A rinse lasts minutes. In the BYU test, 30 minutes of water took the turf from 174°F to 85°F; five minutes later it was back to 120°F, and after 20 minutes it read 164°F. Penn State’s own plots rebounded after about 15 minutes, though watered turf still measured cooler than dry turf three hours later.
• Wet the infill, not just the top. On the BYU field, water beaded on the dry infill and ran across the surface; after a 10-minute cycle the infill was wet only 1 to 2 mm deep. A slow soak gives water time to get in, and water that runs off does little.

Don’t expect a rinse to last longer here than in Penn State’s plots. Their tests ran at 33 to 39% humidity, Greeley’s and Fort Collins’s 90°F hours in 2025 averaged 16.6% and 15.9%, and the Colorado Climate Center notes that Colorado’s low humidity “favors rapid evaporation.”

05Can I hose off hot turf in the middle of the day?

Often not. Penn State’s hot window, noon to 3 p.m., falls inside the no-watering hours several Northern Colorado towns set:

• Johnstown’s 2026 Level 3 drought schedule says “No watering shall occur between 10am and 6pm” (Town of Johnstown).
• Windsor lists a standing rule of no lawn watering from 10 a.m. to 6 p.m. (Town of Windsor).
• Fort Collins’ voluntary Water Shortage Watch asks residents not to water between 10 a.m. and 6 p.m. (City of Fort Collins).

Whether rinsing turf counts as watering depends on how each rule is written and who supplies your water. Do you have to water artificial turf goes through the rules town by town. It depends on your address, so ask your water provider before you rinse at 2 p.m. Not legal advice.

The allowed hours work differently. A rinse after 6 p.m. cools the turf for evening use. A rinse before 10 a.m. won’t carry into the afternoon: in Penn State’s tests, watering before dawn had little effect on the surface temperature later in the day.

06Do heat-reducing yarns and cooling infills work here?

They lower the number, but none of them makes turf behave like grass. The 2024 review found that TPE infill, sun-reflecting “cool” fibers and a water-storing infill product each measured cooler than standard synthetic grass, yet surfaces with the reflective fibers or the water-storing product were still significantly hotter than natural grass. Under Penn State’s heat lamps, a heat-reflective green fiber over black rubber read 158.9°F after three hours, against 165.5°F for a standard green fiber: cooler, and still very hot.

Two cautions for a Northern Colorado yard:

• Reflective fibers send some heat back up. The review notes that the extra reflectance could raise the radiant heat just above the surface, which is where people are.
• Evaporative infills need water, and dry air takes it. They work by holding moisture in the infill. In Penn State’s tests, mixing 20% calcined clay, a water-holding material, into the infill did not lower surface temperature. Here, a wet infill meets the driest air of the day, and rewetting it in the afternoon runs into the 10 a.m.-to-6 p.m. limits above.

For infill choices beyond heat, see artificial turf infill types.

Before trusting a seller’s temperature claim, ask:

• What were the air temperature and humidity when it was measured?
• What time of day was it, and was the sky clear?
• What measured it (an infrared thermometer, a contact probe or a lab heat lamp), and how many readings were taken?
• What was it compared against: standard turf of the same age in the same sun, or grass, or old turf?
• For a cooling infill, how long after wetting was it measured, and with how much water?
• Who ran the test, and is it published?

A claim that answers these can be set beside the numbers on this page. One that can’t is not a test result.