May is one of the warmer months of the year in Fort Smith, with average highs near 25.4°C and lows around 14.6°C (mean 20°C). It is a relatively wet time of year, averaging 155 mm of rainfall and 80% relative humidity across the period.
May is one of the warmer months of the year in Fort Smith. Across 45 years of records, the warmest May in Fort Smith was 2018 — when the month averaged 23°C — while the coldest was 1983 at 17.6°C. Typical May days reach 25.4°C with nights near 14.6°C. The long-term trend is warming, about 0.2°C per decade.
May is a relatively wet time of year in Fort Smith, averaging 155 mm of rainfall. The wettest May on record was 2015 with 385 mm, while the driest was 2012 at 30 mm.
Relative humidity in Fort Smith during May averages 80%. The most humid May was 2015 at 85%, and the least humid was 1988 at 69%.
May receives about 5.7 kWh/m²/day of solar energy in Fort Smith. The sunniest May was 2012 at 6.7 kWh/m²/day, and the cloudiest were 1995 and 2021 at 4.8.
Average wind speed in Fort Smith during May is 1.8 m/s. The windiest May was 2011 at 2.2 m/s, while the calmest were 1987, 1994 and 2023 at 1.4 m/s.
Ranked against the other 11 months using 1981–2025 averages.
| Metric | 1980s | 1990s | 2000s | 2010s | 2020s | Change |
|---|---|---|---|---|---|---|
| Avg Temp | 19.6°C | 19.7°C | 20.4°C | 20.3°C | 20.1°C | +0.5°C |
| Avg High | 25.2°C | 25.1°C | 25.9°C | 25.6°C | 25.1°C | -0.1°C |
| Avg Low | 14.0°C | 14.2°C | 14.8°C | 14.9°C | 15.0°C | +1°C |
| Avg Rain | 155 mm | 156 mm | 130 mm | 170 mm | 172 mm | +17 mm |
May temperatures in Fort Smith have risen by about 1.4°C between 1981–1985 and 2021–2025.
May has ranged from a record low of 1.1°C (2013) to a record high of 36.3°C (2003).
Rainfall in May is a relatively wet time of year, averaging 155 mm, with a wettest year of 385 mm.
One of the best times to visit Fort Smith
May is one of the best times to visit Fort Smith. Expect days averaging 25.4°C and nights around 14.6°C (mean 20°C) — warmer than Fort Smith's yearly average — with higher rainfall (155 mm), so conditions are generally comfortable for sightseeing and outdoor plans.
| Year | Avg High | Avg Temp | Avg Low | Hottest Day | Coldest Day | Rainfall | Humidity | Wind | Solar |
|---|---|---|---|---|---|---|---|---|---|
| 2025 | 24.8°C | 19.7°C | 14.5°C | 31.0°C | 6.8°C | 220 mm | 82% | 1.7 m/s | 5.4 |
| 2024 | 27.2°C | 22.2°C | 17.3°C | 32.1°C | 11.9°C | 145 mm | 82% | 1.6 m/s | 5.4 |
| 2023 | 25.6°C | 20.6°C | 15.5°C | 29.7°C | 3.5°C | 89 mm | 80% | 1.4 m/s | 6 |
| 2022 | 26.0°C | 20.7°C | 15.3°C | 30.9°C | 9.6°C | 172 mm | 83% | 2 m/s | 5.3 |
| 2021 | 23.4°C | 18.6°C | 13.7°C | 28.0°C | 5.8°C | 186 mm | 83% | 1.8 m/s | 4.8 |
| 2020 | 23.6°C | 18.7°C | 13.8°C | 28.2°C | 4.5°C | 219 mm | 84% | 1.9 m/s | 5.7 |
| 2019 | 25.5°C | 20.7°C | 15.8°C | 29.5°C | 7.7°C | 221 mm | 85% | 1.9 m/s | 5.6 |
| 2018 🔥 | 28.0°C | 23.0°C | 18.0°C | 31.4°C | 11.3°C | 108 mm | 82% | 1.5 m/s | 6.3 |
| 2017 | 25.2°C | 19.3°C | 13.4°C | 30.4°C | 5.4°C | 148 mm | 78% | 1.9 m/s | 6.6 |
| 2016 | 24.0°C | 19.1°C | 14.1°C | 28.8°C | 6.6°C | 120 mm | 81% | 1.7 m/s | 5.6 |
| 2015 🌧️ | 24.6°C | 20.0°C | 15.4°C | 28.5°C | 9.1°C | 385 mm | 85% | 1.8 m/s | 4.9 |
| 2014 | 25.7°C | 19.8°C | 13.9°C | 31.1°C | 3.3°C | 131 mm | 76% | 1.9 m/s | 5.8 |
| 2013 | 24.3°C | 18.7°C | 13.1°C | 29.9°C | 1.1°C | 188 mm | 81% | 2 m/s | 5.5 |
| 2012 | 28.8°C | 22.6°C | 16.4°C | 34.7°C | 10.2°C | 30 mm | 71% | 1.7 m/s | 6.7 |
| 2011 | 23.9°C | 18.6°C | 13.3°C | 29.2°C | 3.9°C | 224 mm | 83% | 2.2 m/s | 5.7 |
| 2010 | 26.3°C | 20.9°C | 15.4°C | 30.0°C | 7.4°C | 143 mm | 79% | 1.7 m/s | 5.9 |
| 2009 | 23.7°C | 18.9°C | 14.1°C | 29.3°C | 7.1°C | 198 mm | 84% | 1.7 m/s | 5 |
| 2008 | 25.0°C | 19.6°C | 14.2°C | 30.0°C | 5.5°C | 131 mm | 81% | 2 m/s | 5.9 |
| 2007 | 25.1°C | 20.5°C | 15.8°C | 28.8°C | 9.1°C | 128 mm | 83% | 1.6 m/s | 5.1 |
| 2006 | 26.5°C | 20.8°C | 15.1°C | 34.2°C | 7.7°C | 113 mm | 76% | 1.7 m/s | 6.3 |
| 2005 | 25.8°C | 19.7°C | 13.7°C | 33.6°C | 4.5°C | 83 mm | 72% | 1.6 m/s | 6 |
| 2004 | 26.9°C | 21.3°C | 15.6°C | 32.1°C | 3.2°C | 54 mm | 79% | 1.9 m/s | 5.5 |
| 2003 | 27.7°C | 21.6°C | 15.5°C | 36.3°C | 9.3°C | 132 mm | 74% | 1.8 m/s | 5.3 |
| 2002 | 23.9°C | 18.9°C | 13.8°C | 29.4°C | 6.6°C | 125 mm | 82% | 1.8 m/s | 5.2 |
| 2001 | 26.7°C | 20.7°C | 14.8°C | 32.6°C | 7.3°C | 201 mm | 77% | 1.8 m/s | 6.2 |
| 2000 | 28.0°C | 21.9°C | 15.8°C | 35.7°C | 6.2°C | 131 mm | 74% | 2.1 m/s | 5.6 |
| 1999 | 24.6°C | 19.1°C | 13.6°C | 28.8°C | 6.9°C | 207 mm | 81% | 1.7 m/s | 5.9 |
| 1998 | 28.0°C | 21.9°C | 15.8°C | 33.7°C | 6.8°C | 102 mm | 79% | 1.6 m/s | 6.3 |
| 1997 | 24.3°C | 18.3°C | 12.2°C | 30.9°C | 6.3°C | 73 mm | 76% | 1.8 m/s | 6.3 |
| 1996 | 28.4°C | 22.5°C | 16.6°C | 33.5°C | 8.1°C | 117 mm | 74% | 2 m/s | 5.6 |
| 1995 | 24.0°C | 19.0°C | 14.0°C | 29.8°C | 4.0°C | 188 mm | 84% | 1.8 m/s | 4.8 |
| 1994 | 24.7°C | 18.9°C | 13.1°C | 29.6°C | 2.6°C | 107 mm | 79% | 1.4 m/s | 6.3 |
| 1993 | 23.2°C | 18.2°C | 13.3°C | 27.0°C | 7.9°C | 172 mm | 84% | 1.7 m/s | 5.4 |
| 1992 | 23.8°C | 18.8°C | 13.7°C | 28.5°C | 4.4°C | 152 mm | 79% | 1.5 m/s | 5.2 |
| 1991 | 26.6°C | 21.8°C | 17.0°C | 31.2°C | 5.8°C | 115 mm | 84% | 1.6 m/s | 5.8 |
| 1990 | 23.7°C | 18.4°C | 13.0°C | 28.0°C | 6.4°C | 325 mm | 85% | 2 m/s | 5.3 |
| 1989 | 24.6°C | 19.3°C | 13.9°C | 30.2°C | 4.3°C | 211 mm | 81% | 1.8 m/s | 5.7 |
| 1988 | 26.8°C | 19.9°C | 12.9°C | 32.2°C | 7.8°C | 48 mm | 69% | 1.7 m/s | 6.1 |
| 1987 | 27.6°C | 22.7°C | 17.8°C | 32.5°C | 12.5°C | 176 mm | 78% | 1.4 m/s | 6 |
| 1986 | 24.5°C | 19.6°C | 14.8°C | 28.1°C | 8.6°C | 155 mm | 81% | 1.5 m/s | 5.5 |
| 1985 | 24.9°C | 19.5°C | 14.1°C | 30.4°C | 8.2°C | 83 mm | 82% | 1.7 m/s | 6.1 |
| 1984 | 24.7°C | 18.7°C | 12.6°C | 29.6°C | 5.6°C | 168 mm | 78% | 1.9 m/s | 5.4 |
| 1983 ❄️ | 23.4°C | 17.6°C | 11.7°C | 27.1°C | 6.4°C | 171 mm | 79% | 1.9 m/s | — |
| 1982 | 26.0°C | 20.8°C | 15.5°C | 29.9°C | 7.5°C | 197 mm | 79% | 1.8 m/s | — |
| 1981 | 24.0°C | 18.4°C | 12.7°C | 28.3°C | 5.5°C | 190 mm | 77% | 1.9 m/s | — |
Actual recorded May data for each year, 1981–2025 — sourced from NASA POWER.
The average high in May is around 25.4°C with lows near 14.6°C (mean 20°C), based on 45 years of NASA POWER data.
May averages 155 mm of rainfall in Fort Smith, a relatively wet time of year. The wettest on record was 385 mm in 2015.
The hottest May reached 36.3°C in 2003. The coldest dipped to 1.1°C in 2013.
Comparing the earliest years on record (1981–1985) with the most recent (2021–2025), average May temperatures have risen by about 1.4°C. Daytime highs moved from 24.6°C to 25.4°C and overnight lows from 13.3°C to 15.3°C over the same span.
May is one of the warmer months of the year in Fort Smith and a relatively wet time of year, so plan for around 25.4°C daytime highs and 14.6°C at night.
Not quite — May is the 8th coolest month in Fort Smith, averaging 20°C.
For May in Fort Smith, pack light layers you can adjust through the day, with typical highs of 25.4°C and lows of 14.6°C. Bring an umbrella or light rain jacket too.
Relative humidity in May averages 80% — quite humid.
Average wind speed in May is 1.8 m/s. The windiest May on record averaged 2.2 m/s (2011).
The wettest May on record was 2015 with 385 mm. On average, May sees 155 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 Fort Smith 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.
