May is one of the warmer months of the year in Williams Lake, with average highs near 15.4°C and lows around 2.4°C (mean 8.9°C). It is about average for rainfall, averaging 50 mm of rainfall and 70% relative humidity across the period.
May is one of the warmer months of the year in Williams Lake. Across 45 years of records, the warmest May in Williams Lake was 2023 — when the month averaged 13.3°C — while the coldest was 1984 at 5.6°C. Typical May days reach 15.4°C with nights near 2.4°C. The long-term trend is warming, about 0.2°C per decade.
May is about average for rainfall in Williams Lake, averaging 50 mm of rainfall. The wettest May on record was 2011 with 116 mm, while the driest was 2001 at 19 mm.
Relative humidity in Williams Lake during May averages 70%. The most humid May was 2011 at 78%, and the least humid was 1987 at 60%.
May receives about 5.5 kWh/m²/day of solar energy in Williams Lake. The sunniest Mays were 1995 and 1998 at 6.2 kWh/m²/day, and the cloudiest was 2011 at 4.7.
Average wind speed in Williams Lake during May is 0.1 m/s. The windiest Mays were 2019, 2021 and 2023, among others at 0.2 m/s, while the calmest were 2022, 2024 and 2025, among others at 0.1 m/s.
Ranked against the other 11 months using 1981–2025 averages.
| Metric | 1980s | 1990s | 2000s | 2010s | 2020s | Change |
|---|---|---|---|---|---|---|
| Avg Temp | 8.5°C | 9.2°C | 8.2°C | 9.4°C | 9.0°C | +0.5°C |
| Avg High | 15.4°C | 15.8°C | 14.7°C | 15.7°C | 15.2°C | -0.2°C |
| Avg Low | 1.7°C | 2.6°C | 1.7°C | 3.1°C | 2.8°C | +1.1°C |
| Avg Rain | 43 mm | 43 mm | 46 mm | 59 mm | 61 mm | +18 mm |
May temperatures in Williams Lake have risen by about 0.9°C between 1981–1985 and 2021–2025.
May has ranged from a record low of -5.7°C (2002) to a record high of 33.7°C (1983).
Rainfall in May is about average for rainfall, averaging 50 mm, with a wettest year of 116 mm.
Daytime highs and overnight lows have shifted differently — highs rose about 0°C per decade while lows rose 0.3°C per decade, narrowing the gap between day and night.
A good time to visit Williams Lake
May is a good time to visit Williams Lake, with days averaging 15.4°C and nights around 2.4°C (mean 8.9°C, warmer than Williams Lake's yearly average) and moderate rainfall. August and July 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 | 15.1°C | 9.2°C | 3.3°C | 24.4°C | -1.7°C | 63 mm | 72% | 0.1 m/s | 5.2 |
| 2024 | 14.9°C | 8.2°C | 1.6°C | 24.0°C | -4.3°C | 78 mm | 70% | 0.1 m/s | 5.1 |
| 2023 🔥 | 19.8°C | 13.3°C | 6.8°C | 28.1°C | 1.0°C | 85 mm | 73% | 0.2 m/s | 6.1 |
| 2022 | 12.2°C | 6.7°C | 1.2°C | 17.7°C | -3.0°C | 47 mm | 74% | 0.1 m/s | 5 |
| 2021 | 14.1°C | 8.1°C | 2.1°C | 20.7°C | -4.0°C | 42 mm | 73% | 0.2 m/s | 5.4 |
| 2020 | 14.9°C | 8.5°C | 2.1°C | 19.0°C | -4.5°C | 53 mm | 76% | 0.1 m/s | 5.8 |
| 2019 | 18.0°C | 11.4°C | 4.8°C | 26.5°C | -1.1°C | 29 mm | 70% | 0.2 m/s | 5.6 |
| 2018 | 18.8°C | 12.0°C | 5.2°C | 26.4°C | -0.5°C | 27 mm | 71% | 0.1 m/s | 5.9 |
| 2017 | 16.3°C | 9.7°C | 3.2°C | 25.8°C | -4.3°C | 66 mm | 73% | 0.2 m/s | 5.6 |
| 2016 | 15.8°C | 9.6°C | 3.5°C | 24.0°C | -0.1°C | 69 mm | 71% | 0.1 m/s | 5.6 |
| 2015 | 17.0°C | 10.6°C | 4.1°C | 23.9°C | -4.6°C | 27 mm | 72% | 0.2 m/s | 6 |
| 2014 | 14.3°C | 8.7°C | 3.1°C | 20.6°C | -3.0°C | 111 mm | 77% | 0.2 m/s | 5.1 |
| 2013 | 16.1°C | 9.9°C | 3.7°C | 26.6°C | -5.3°C | 68 mm | 73% | 0.2 m/s | 5.4 |
| 2012 | 14.4°C | 7.5°C | 0.6°C | 21.8°C | -4.5°C | 37 mm | 68% | 0.1 m/s | 5.9 |
| 2011 🌧️ | 12.9°C | 7.0°C | 1.0°C | 19.5°C | -3.6°C | 116 mm | 78% | 0.2 m/s | 4.7 |
| 2010 | 13.7°C | 7.5°C | 1.3°C | 21.2°C | -5.2°C | 45 mm | 67% | 0.1 m/s | 5.4 |
| 2009 | 13.9°C | 7.4°C | 0.8°C | 24.0°C | -3.8°C | 42 mm | 71% | 0.1 m/s | 5.8 |
| 2008 | 15.1°C | 8.9°C | 2.7°C | 25.9°C | -2.5°C | 55 mm | 76% | 0.2 m/s | 5.2 |
| 2007 | 15.0°C | 7.9°C | 0.7°C | 24.3°C | -4.2°C | 24 mm | 71% | 0.1 m/s | 5.8 |
| 2006 | 16.1°C | 9.2°C | 2.3°C | 29.6°C | -5.4°C | 43 mm | 68% | 0.1 m/s | 5.7 |
| 2005 | 16.8°C | 10.6°C | 4.4°C | 30.2°C | -0.3°C | 56 mm | 72% | 0.1 m/s | 5.7 |
| 2004 | 14.8°C | 8.6°C | 2.5°C | 22.9°C | -3.9°C | 56 mm | 70% | 0.1 m/s | 5.4 |
| 2003 | 13.8°C | 7.5°C | 1.1°C | 23.2°C | -5.0°C | 31 mm | 68% | 0.1 m/s | 5.3 |
| 2002 | 12.7°C | 6.7°C | 0.7°C | 20.0°C | -5.7°C | 83 mm | 73% | 0.2 m/s | 4.9 |
| 2001 | 15.0°C | 8.2°C | 1.5°C | 24.1°C | -5.1°C | 19 mm | 65% | 0.1 m/s | 5.3 |
| 2000 | 13.5°C | 7.0°C | 0.6°C | 19.8°C | -3.9°C | 51 mm | 70% | 0.1 m/s | 5.5 |
| 1999 | 11.9°C | 6.1°C | 0.2°C | 24.9°C | -4.0°C | 79 mm | 75% | 0.1 m/s | 5.2 |
| 1998 | 19.1°C | 12.0°C | 4.9°C | 24.8°C | 0.9°C | 38 mm | 67% | 0.2 m/s | 6.2 |
| 1997 | 15.6°C | 8.9°C | 2.2°C | 23.9°C | -3.9°C | 34 mm | 73% | 0.2 m/s | 5.8 |
| 1996 | 11.2°C | 5.7°C | 0.2°C | 18.2°C | -3.9°C | 67 mm | 76% | 0.1 m/s | 5.5 |
| 1995 | 17.4°C | 10.2°C | 2.9°C | 26.5°C | -2.1°C | 28 mm | 65% | 0.2 m/s | 6.2 |
| 1994 | 16.6°C | 9.9°C | 3.3°C | 23.3°C | -3.4°C | 25 mm | 64% | 0.1 m/s | 5.4 |
| 1993 | 19.8°C | 12.6°C | 5.3°C | 30.5°C | -3.0°C | 40 mm | 65% | 0.1 m/s | 5.8 |
| 1992 | 16.6°C | 9.3°C | 2.0°C | 28.0°C | -3.6°C | 29 mm | 63% | 0.1 m/s | 5.9 |
| 1991 | 15.6°C | 9.0°C | 2.3°C | 21.6°C | -2.3°C | 20 mm | 69% | 0.1 m/s | 5.9 |
| 1990 | 14.5°C | 8.5°C | 2.5°C | 22.1°C | -3.2°C | 71 mm | 74% | 0.1 m/s | 5.4 |
| 1989 | 16.5°C | 9.4°C | 2.2°C | 23.5°C | -2.1°C | 61 mm | 65% | 0.1 m/s | 5.5 |
| 1988 | 16.3°C | 9.2°C | 2.2°C | 26.3°C | -5.4°C | 40 mm | 61% | 0.1 m/s | 5.2 |
| 1987 | 16.8°C | 9.5°C | 2.2°C | 26.0°C | -2.2°C | 36 mm | 60% | 0.1 m/s | 5.7 |
| 1986 | 14.5°C | 7.7°C | 0.9°C | 29.1°C | -5.6°C | 40 mm | 69% | 0.1 m/s | 5.4 |
| 1985 | 16.3°C | 9.3°C | 2.3°C | 26.0°C | -4.3°C | 29 mm | 69% | 0.1 m/s | 6 |
| 1984 ❄️ | 11.6°C | 5.6°C | -0.3°C | 20.5°C | -4.4°C | 38 mm | 71% | 0.1 m/s | 5.4 |
| 1983 | 18.0°C | 10.3°C | 2.7°C | 33.7°C | -2.2°C | 23 mm | 63% | 0.1 m/s | — |
| 1982 | 13.5°C | 6.8°C | 0.1°C | 22.4°C | -4.6°C | 56 mm | 73% | 0.1 m/s | — |
| 1981 | 15.3°C | 9.1°C | 2.9°C | 22.8°C | -3.2°C | 67 mm | 72% | 0.1 m/s | — |
Actual recorded May data for each year, 1981–2025 — sourced from NASA POWER.
The average high in May is around 15.4°C with lows near 2.4°C (mean 8.9°C), based on 45 years of NASA POWER data.
May averages 50 mm of rainfall in Williams Lake, about average for rainfall. The wettest on record was 116 mm in 2011.
The hottest May reached 33.7°C in 1983. The coldest dipped to -5.7°C in 2002.
Comparing the earliest years on record (1981–1985) with the most recent (2021–2025), average May temperatures have risen by about 0.9°C. Daytime highs moved from 14.9°C to 15.2°C and overnight lows from 1.5°C to 3°C over the same span.
May is one of the warmer months of the year in Williams Lake and about average for rainfall, so plan for around 15.4°C daytime highs and 2.4°C at night.
Not quite — May is the 8th coolest month in Williams Lake, averaging 8.9°C.
For May in Williams Lake, pack warm layers and a jacket for chilly mornings, with typical highs of 15.4°C and lows of 2.4°C.
Relative humidity in May averages 70% — moderately humid.
Average wind speed in May is 0.1 m/s. The windiest May on record averaged 0.2 m/s (1995).
The wettest May on record was 2011 with 116 mm. On average, May sees 50 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 Williams Lake 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.
