April is one of the cooler months of the year in Knoxville, with average highs near 19.7°C and lows around 7.4°C (mean 13.6°C). It is about average for rainfall, averaging 108 mm of rainfall and 77% relative humidity across the period.
April is one of the cooler months of the year in Knoxville. Across 45 years of records, the warmest April in Knoxville was 2017 — when the month averaged 16.5°C — while the coldest were 1983 and 1997 at 10.8°C. Typical April days reach 19.7°C with nights near 7.4°C. The long-term trend is warming, about 0.4°C per decade.
April is about average for rainfall in Knoxville, averaging 108 mm of rainfall. The wettest April on record was 1998 with 264 mm, while the driest was 1986 at 39 mm.
Relative humidity in Knoxville during April averages 77%. The most humid April was 2003 at 82%, and the least humid was 1986 at 69%.
April receives about 5.2 kWh/m²/day of solar energy in Knoxville. The sunniest April was 2010 at 5.9 kWh/m²/day, and the cloudiest were 1984 and 2000 at 4.4.
Average wind speed in Knoxville during April is 1 m/s. The windiest April was 2011 at 1.3 m/s, while the calmest were 2015, 2021 and 2023, among others at 0.9 m/s.
Ranked against the other 11 months using 1981–2025 averages.
| Metric | 1980s | 1990s | 2000s | 2010s | 2020s | Change |
|---|---|---|---|---|---|---|
| Avg Temp | 12.7°C | 13.1°C | 13.9°C | 14.4°C | 13.8°C | +1.1°C |
| Avg High | 18.8°C | 19.2°C | 20.0°C | 20.5°C | 19.8°C | +1°C |
| Avg Low | 6.6°C | 6.9°C | 7.8°C | 8.2°C | 7.7°C | +1.1°C |
| Avg Rain | 95 mm | 106 mm | 109 mm | 124 mm | 99 mm | +4 mm |
April temperatures in Knoxville have risen by about 1.4°C between 1981–1985 and 2021–2025.
April has ranged from a record low of -5.9°C (2007) to a record high of 30.3°C (1986).
Rainfall in April is about average for rainfall, averaging 108 mm, with a wettest year of 264 mm.
A good time to visit Knoxville
April is a good time to visit Knoxville, with days averaging 19.7°C and nights around 7.4°C (mean 13.6°C, close to Knoxville's yearly average) and higher rainfall. September and June are marginally more temperate, but April still suits most travellers.
| Year | Avg High | Avg Temp | Avg Low | Hottest Day | Coldest Day | Rainfall | Humidity | Wind | Solar |
|---|---|---|---|---|---|---|---|---|---|
| 2025 | 21.7°C | 15.8°C | 9.8°C | 28.5°C | -2.1°C | 101 mm | 77% | 1 m/s | 5.4 |
| 2024 | 20.8°C | 15.0°C | 9.1°C | 28.0°C | 0.8°C | 84 mm | 77% | 1 m/s | 5 |
| 2023 | 20.3°C | 13.8°C | 7.3°C | 26.4°C | 1.0°C | 81 mm | 75% | 0.9 m/s | 5.2 |
| 2022 | 19.3°C | 12.9°C | 6.5°C | 26.5°C | -0.4°C | 94 mm | 76% | 1 m/s | 5.3 |
| 2021 | 18.8°C | 12.9°C | 7.0°C | 25.8°C | -5.0°C | 41 mm | 75% | 0.9 m/s | 5.8 |
| 2020 | 18.1°C | 12.2°C | 6.3°C | 24.9°C | 0.1°C | 191 mm | 77% | 1.1 m/s | 5.4 |
| 2019 | 21.0°C | 15.1°C | 9.2°C | 26.9°C | -4.5°C | 127 mm | 77% | 1 m/s | 5.4 |
| 2018 | 17.3°C | 11.0°C | 4.7°C | 23.1°C | -4.6°C | 117 mm | 78% | 1 m/s | 5.2 |
| 2017 🔥 | 22.2°C | 16.5°C | 10.7°C | 28.7°C | 1.5°C | 185 mm | 79% | 1 m/s | 5 |
| 2016 | 20.3°C | 14.0°C | 7.6°C | 26.6°C | -2.0°C | 81 mm | 75% | 1 m/s | 5.7 |
| 2015 | 20.4°C | 14.5°C | 8.6°C | 24.9°C | -0.5°C | 143 mm | 81% | 0.9 m/s | 4.7 |
| 2014 | 20.8°C | 14.3°C | 7.7°C | 26.5°C | -3.7°C | 103 mm | 77% | 1 m/s | 5.3 |
| 2013 | 19.2°C | 13.1°C | 7.1°C | 26.1°C | -1.1°C | 158 mm | 80% | 0.9 m/s | 5.3 |
| 2012 | 20.6°C | 14.7°C | 8.8°C | 27.2°C | -0.3°C | 79 mm | 78% | 0.9 m/s | 5.5 |
| 2011 | 21.3°C | 15.2°C | 9.2°C | 27.3°C | -0.2°C | 171 mm | 78% | 1.3 m/s | 5.5 |
| 2010 | 21.8°C | 15.3°C | 8.8°C | 27.9°C | 1.8°C | 74 mm | 74% | 1 m/s | 5.9 |
| 2009 | 19.3°C | 13.3°C | 7.2°C | 27.3°C | -2.2°C | 83 mm | 78% | 1.1 m/s | 5.1 |
| 2008 | 19.9°C | 13.6°C | 7.4°C | 25.3°C | 0.1°C | 94 mm | 77% | 1 m/s | 5.3 |
| 2007 | 18.4°C | 12.0°C | 5.7°C | 27.3°C | -5.9°C | 99 mm | 71% | 1.1 m/s | 5.5 |
| 2006 | 21.9°C | 15.9°C | 9.9°C | 26.9°C | -1.8°C | 165 mm | 77% | 1 m/s | 5.3 |
| 2005 | 19.2°C | 13.4°C | 7.5°C | 25.4°C | -0.3°C | 134 mm | 79% | 1 m/s | 4.8 |
| 2004 | 19.8°C | 13.6°C | 7.4°C | 27.4°C | -1.5°C | 77 mm | 77% | 0.9 m/s | 5.2 |
| 2003 | 20.3°C | 14.6°C | 8.8°C | 26.3°C | 2.2°C | 164 mm | 82% | 0.9 m/s | 4.9 |
| 2002 | 21.1°C | 15.0°C | 8.9°C | 27.8°C | -1.0°C | 59 mm | 77% | 1 m/s | 5.3 |
| 2001 | 21.2°C | 15.1°C | 9.0°C | 27.5°C | -1.7°C | 63 mm | 76% | 1 m/s | 5.3 |
| 2000 | 18.4°C | 12.3°C | 6.3°C | 23.8°C | -3.1°C | 153 mm | 78% | 1 m/s | 4.4 |
| 1999 | 20.8°C | 14.9°C | 9.1°C | 26.7°C | 0.7°C | 71 mm | 79% | 1 m/s | 5 |
| 1998 🌧️ | 18.5°C | 13.2°C | 7.8°C | 23.5°C | 0.4°C | 264 mm | 81% | 1.1 m/s | 4.6 |
| 1997 | 17.2°C | 10.8°C | 4.4°C | 23.3°C | -4.0°C | 102 mm | 75% | 0.9 m/s | 5.5 |
| 1996 | 17.6°C | 11.2°C | 4.7°C | 25.3°C | -4.2°C | 95 mm | 78% | 1.1 m/s | 5.2 |
| 1995 | 20.9°C | 14.3°C | 7.7°C | 29.1°C | -1.5°C | 49 mm | 73% | 1 m/s | 5.3 |
| 1994 | 21.0°C | 14.8°C | 8.6°C | 28.9°C | -0.7°C | 177 mm | 80% | 1 m/s | 5.6 |
| 1993 | 17.7°C | 11.5°C | 5.3°C | 23.9°C | -2.5°C | 71 mm | 77% | 1.1 m/s | 5.2 |
| 1992 | 18.7°C | 12.8°C | 6.9°C | 25.2°C | -4.4°C | 54 mm | 79% | 0.9 m/s | 4.8 |
| 1991 | 20.8°C | 15.1°C | 9.3°C | 25.7°C | 1.5°C | 104 mm | 81% | 0.9 m/s | 4.6 |
| 1990 | 18.4°C | 11.9°C | 5.5°C | 27.4°C | -4.4°C | 78 mm | 79% | 0.9 m/s | 5.2 |
| 1989 | 17.9°C | 12.3°C | 6.7°C | 26.1°C | -4.8°C | 105 mm | 80% | 0.9 m/s | 5 |
| 1988 | 19.0°C | 12.4°C | 5.9°C | 26.4°C | 0.2°C | 84 mm | 75% | 1.1 m/s | 5.2 |
| 1987 | 17.3°C | 11.6°C | 6.0°C | 27.5°C | -5.1°C | 98 mm | 81% | 1 m/s | 5.2 |
| 1986 | 21.0°C | 14.1°C | 7.2°C | 30.3°C | -3.6°C | 39 mm | 69% | 1 m/s | 5.6 |
| 1985 | 20.5°C | 14.2°C | 7.9°C | 27.6°C | -4.0°C | 60 mm | 74% | 1 m/s | 5.6 |
| 1984 | 17.9°C | 12.3°C | 6.8°C | 26.4°C | -0.1°C | 107 mm | 82% | 1.1 m/s | 4.4 |
| 1983 ❄️ | 16.6°C | 10.8°C | 5.0°C | 23.3°C | -5.3°C | 153 mm | 79% | 1.1 m/s | — |
| 1982 | 17.1°C | 10.9°C | 4.8°C | 24.6°C | -5.6°C | 80 mm | 76% | 1.1 m/s | — |
| 1981 | 22.1°C | 15.4°C | 8.7°C | 26.5°C | 1.1°C | 128 mm | 76% | 1.1 m/s | — |
Actual recorded April data for each year, 1981–2025 — sourced from NASA POWER.
The average high in April is around 19.7°C with lows near 7.4°C (mean 13.6°C), based on 45 years of NASA POWER data.
April averages 108 mm of rainfall in Knoxville, about average for rainfall. The wettest on record was 264 mm in 1998.
The hottest April reached 30.3°C in 1986. The coldest dipped to -5.9°C in 2007.
Comparing the earliest years on record (1981–1985) with the most recent (2021–2025), average April temperatures have risen by about 1.4°C. Daytime highs moved from 18.8°C to 20.2°C and overnight lows from 6.6°C to 7.9°C over the same span.
April is one of the cooler months of the year in Knoxville and about average for rainfall, so plan for around 19.7°C daytime highs and 7.4°C at night.
Not quite — April is the 6th coolest month in Knoxville, averaging 13.6°C.
For April in Knoxville, pack warm layers and a jacket for chilly mornings, with typical highs of 19.7°C and lows of 7.4°C. Bring an umbrella or light rain jacket too.
Relative humidity in April averages 77% — quite humid.
Average wind speed in April is 1 m/s. The windiest April on record averaged 1.3 m/s (2011).
The wettest April on record was 1998 with 264 mm. On average, April sees 108 mm.
All figures are derived from NASA POWER (Prediction Of Worldwide Energy Resources), based on MERRA-2 satellite reanalysis, covering 1981–2025.
Explore how the weather in Knoxville behaves each April, based on 45 years of NASA POWER climate data from 1981 to 2025. This page breaks down average temperatures, rainfall, humidity, wind and solar radiation for April specifically, along with year-by-year records and how the month has changed over the decades.
