May is one of the warmer months of the year in Johnson City, with average highs near 22.8°C and lows around 11.7°C (mean 17.3°C). It is a relatively wet time of year, averaging 111 mm of rainfall and 78% relative humidity across the period.
May is one of the warmer months of the year in Johnson City. Across 45 years of records, the warmest May in Johnson City was 2018 — when the month averaged 20.1°C — while the coldest was 1989 at 14.1°C. Typical May days reach 22.8°C with nights near 11.7°C. The long-term trend is warming, about 0.4°C per decade.
May is a relatively wet time of year in Johnson City, averaging 111 mm of rainfall. The wettest May on record was 1984 with 201 mm, while the driest was 2007 at 42 mm.
Relative humidity in Johnson City during May averages 78%. The most humid May was 2003 at 84%, and the least humid was 2007 at 63%.
May receives about 5.7 kWh/m²/day of solar energy in Johnson City. The sunniest May was 1999 at 6.7 kWh/m²/day, and the cloudiest were 1989 and 2003 at 4.8.
Average wind speed in Johnson City during May is 1 m/s. The windiest May was 1997 at 1.4 m/s, while the calmest were 1982, 1987 and 2012 at 0.8 m/s.
Ranked against the other 11 months using 1981–2025 averages.
| Metric | 1980s | 1990s | 2000s | 2010s | 2020s | Change |
|---|---|---|---|---|---|---|
| Avg Temp | 16.6°C | 16.7°C | 17.4°C | 18.2°C | 17.3°C | +0.7°C |
| Avg High | 22.5°C | 22.1°C | 23.2°C | 23.5°C | 22.7°C | +0.2°C |
| Avg Low | 10.7°C | 11.2°C | 11.6°C | 13.0°C | 11.9°C | +1.2°C |
| Avg Rain | 121 mm | 116 mm | 96 mm | 106 mm | 124 mm | +3 mm |
May temperatures in Johnson City have risen by about 1.1°C between 1981–1985 and 2021–2025.
May has ranged from a record low of -1.7°C (1989) to a record high of 32.5°C (2007).
Rainfall in May is a relatively wet time of year, averaging 111 mm, with a wettest year of 201 mm.
Daytime highs and overnight lows have shifted differently — highs rose about 0.2°C per decade while lows rose 0.5°C per decade, narrowing the gap between day and night.
A good time to visit Johnson City
May is a good time to visit Johnson City, with days averaging 22.8°C and nights around 11.7°C (mean 17.3°C, warmer than Johnson City's yearly average) and higher rainfall. June and September are marginally more temperate, but May still suits most travellers.
| Year | Avg High | Avg Temp | Avg Low | Hottest Day | Coldest Day | Rainfall | Humidity | Wind | Solar |
|---|---|---|---|---|---|---|---|---|---|
| 2025 | 22.0°C | 17.1°C | 12.2°C | 26.0°C | 5.9°C | 140 mm | 81% | 1.1 m/s | 5.1 |
| 2024 | 24.2°C | 19.1°C | 14.0°C | 27.9°C | 6.9°C | 164 mm | 81% | 0.9 m/s | 5.3 |
| 2023 | 22.4°C | 16.7°C | 11.1°C | 26.2°C | 3.1°C | 93 mm | 78% | 1 m/s | 5.8 |
| 2022 | 24.9°C | 18.9°C | 12.8°C | 30.7°C | 6.1°C | 143 mm | 76% | 1.1 m/s | 5.9 |
| 2021 | 22.0°C | 16.4°C | 10.9°C | 28.3°C | 3.6°C | 65 mm | 77% | 1 m/s | 5.7 |
| 2020 | 20.5°C | 15.3°C | 10.1°C | 26.7°C | 0.3°C | 137 mm | 83% | 1.2 m/s | 5.6 |
| 2019 | 24.8°C | 19.7°C | 14.7°C | 28.6°C | 6.5°C | 92 mm | 81% | 1 m/s | 6.2 |
| 2018 🔥 | 25.0°C | 20.1°C | 15.3°C | 28.4°C | 6.0°C | 154 mm | 83% | 0.9 m/s | 5.6 |
| 2017 | 22.4°C | 17.4°C | 12.5°C | 27.9°C | 4.6°C | 173 mm | 81% | 1.2 m/s | 5.6 |
| 2016 | 21.7°C | 16.5°C | 11.4°C | 27.7°C | 1.6°C | 103 mm | 80% | 1 m/s | 5.4 |
| 2015 | 24.6°C | 18.8°C | 13.0°C | 27.7°C | 5.8°C | 44 mm | 76% | 0.9 m/s | 6.5 |
| 2014 | 23.9°C | 18.0°C | 12.2°C | 29.2°C | 2.9°C | 72 mm | 76% | 1 m/s | 6.3 |
| 2013 | 21.3°C | 16.1°C | 10.9°C | 27.1°C | 2.0°C | 121 mm | 81% | 1.2 m/s | 5.9 |
| 2012 | 24.3°C | 19.3°C | 14.2°C | 28.8°C | 5.4°C | 94 mm | 79% | 0.8 m/s | 6 |
| 2011 | 22.5°C | 17.2°C | 12.0°C | 31.5°C | 1.3°C | 101 mm | 80% | 1 m/s | 5.5 |
| 2010 | 24.2°C | 18.8°C | 13.4°C | 28.2°C | 2.6°C | 107 mm | 80% | 1.1 m/s | 6 |
| 2009 | 22.3°C | 17.2°C | 12.1°C | 25.3°C | 1.4°C | 154 mm | 83% | 1.1 m/s | 5.3 |
| 2008 | 22.6°C | 16.7°C | 10.7°C | 28.6°C | 5.5°C | 62 mm | 73% | 1.3 m/s | 5.7 |
| 2007 | 26.2°C | 18.9°C | 11.6°C | 32.5°C | 3.1°C | 42 mm | 63% | 0.9 m/s | 6.4 |
| 2006 | 21.8°C | 16.1°C | 10.5°C | 31.7°C | 5.6°C | 85 mm | 76% | 1 m/s | 5.7 |
| 2005 | 21.2°C | 15.5°C | 9.8°C | 26.4°C | 1.5°C | 61 mm | 77% | 1 m/s | 6.2 |
| 2004 | 24.2°C | 19.1°C | 14.1°C | 27.5°C | 1.2°C | 137 mm | 82% | 1 m/s | 5.6 |
| 2003 | 21.8°C | 17.2°C | 12.6°C | 26.1°C | 8.0°C | 144 mm | 84% | 1.2 m/s | 4.8 |
| 2002 | 22.6°C | 16.3°C | 10.0°C | 28.9°C | 0.8°C | 86 mm | 75% | 1.1 m/s | 5.6 |
| 2001 | 24.0°C | 17.8°C | 11.6°C | 29.1°C | 6.4°C | 109 mm | 72% | 1 m/s | 5.6 |
| 2000 | 25.1°C | 18.9°C | 12.7°C | 29.2°C | 6.3°C | 78 mm | 72% | 1.1 m/s | 5.8 |
| 1999 | 23.2°C | 17.0°C | 10.9°C | 27.7°C | 3.0°C | 82 mm | 72% | 1 m/s | 6.7 |
| 1998 | 23.4°C | 18.7°C | 14.0°C | 28.8°C | 7.3°C | 135 mm | 83% | 0.9 m/s | 5.5 |
| 1997 | 20.4°C | 14.2°C | 7.9°C | 25.4°C | 1.1°C | 98 mm | 76% | 1.4 m/s | 6 |
| 1996 | 23.0°C | 17.8°C | 12.7°C | 28.8°C | 1.1°C | 156 mm | 82% | 1.1 m/s | 5.8 |
| 1995 | 22.7°C | 17.2°C | 11.7°C | 26.8°C | 4.7°C | 139 mm | 78% | 1.1 m/s | 5.5 |
| 1994 | 20.7°C | 14.6°C | 8.6°C | 26.3°C | 2.4°C | 80 mm | 78% | 1.1 m/s | 6 |
| 1993 | 22.3°C | 17.0°C | 11.7°C | 26.1°C | 5.7°C | 83 mm | 79% | 1 m/s | 5.5 |
| 1992 | 20.1°C | 14.8°C | 9.5°C | 26.0°C | 1.2°C | 118 mm | 80% | 0.9 m/s | 5 |
| 1991 | 24.3°C | 19.3°C | 14.2°C | 29.1°C | 5.8°C | 113 mm | 82% | 0.9 m/s | 5.6 |
| 1990 | 21.3°C | 16.1°C | 10.9°C | 25.8°C | 2.5°C | 158 mm | 80% | 1.2 m/s | 5.2 |
| 1989 ❄️ | 19.7°C | 14.1°C | 8.5°C | 27.1°C | -1.7°C | 133 mm | 81% | 1.2 m/s | 4.8 |
| 1988 | 22.8°C | 16.4°C | 10.0°C | 30.8°C | 2.8°C | 80 mm | 69% | 1.1 m/s | 5.8 |
| 1987 | 24.2°C | 19.1°C | 13.9°C | 27.5°C | 6.6°C | 79 mm | 79% | 0.8 m/s | 6.2 |
| 1986 | 23.5°C | 17.4°C | 11.3°C | 27.5°C | 0.3°C | 120 mm | 74% | 0.9 m/s | 4.9 |
| 1985 | 23.8°C | 17.5°C | 11.3°C | 29.5°C | 3.8°C | 80 mm | 72% | 1.1 m/s | 5.5 |
| 1984 🌧️ | 20.8°C | 15.0°C | 9.1°C | 26.0°C | 1.9°C | 201 mm | 80% | 1.2 m/s | 5.1 |
| 1983 | 21.0°C | 15.2°C | 9.4°C | 24.3°C | 0.5°C | 154 mm | 78% | 1.2 m/s | — |
| 1982 | 24.1°C | 18.7°C | 13.4°C | 27.8°C | 5.2°C | 100 mm | 78% | 0.8 m/s | — |
| 1981 | 22.2°C | 16.0°C | 9.7°C | 26.9°C | 2.8°C | 138 mm | 71% | 1.1 m/s | — |
Actual recorded May data for each year, 1981–2025 — sourced from NASA POWER.
The average high in May is around 22.8°C with lows near 11.7°C (mean 17.3°C), based on 45 years of NASA POWER data.
May averages 111 mm of rainfall in Johnson City, a relatively wet time of year. The wettest on record was 201 mm in 1984.
The hottest May reached 32.5°C in 2007. The coldest dipped to -1.7°C in 1989.
Comparing the earliest years on record (1981–1985) with the most recent (2021–2025), average May temperatures have risen by about 1.1°C. Daytime highs moved from 22.4°C to 23.1°C and overnight lows from 10.6°C to 12.2°C over the same span.
May is one of the warmer months of the year in Johnson City and a relatively wet time of year, so plan for around 22.8°C daytime highs and 11.7°C at night.
Not quite — May is the 8th coolest month in Johnson City, averaging 17.3°C.
For May in Johnson City, pack light layers you can adjust through the day, with typical highs of 22.8°C and lows of 11.7°C. Bring an umbrella or light rain jacket too.
Relative humidity in May averages 78% — quite humid.
Average wind speed in May is 1 m/s. The windiest May on record averaged 1.4 m/s (1997).
The wettest May on record was 1984 with 201 mm. On average, May sees 111 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 Johnson City behaves each May, 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 May specifically, along with year-by-year records and how the month has changed over the decades.
