January is one of the warmer months of the year in Blenheim, with average highs near 21.7°C and lows around 11.1°C (mean 16.4°C). It is one of the drier months, averaging 59 mm of rainfall and 71% relative humidity across the period.
January is one of the warmer months of the year in Blenheim. Across 45 years of records, the warmest January in Blenheim was 2018 — when the month averaged 18.9°C — while the coldest was 1993 at 13.6°C. Typical January days reach 21.7°C with nights near 11.1°C. The long-term January temperature trend is broadly flat.
January is one of the drier months in Blenheim, averaging 59 mm of rainfall. The wettest January on record was 1985 with 172 mm, while the driest was 2015 at 9 mm.
Relative humidity in Blenheim during January averages 71%. The most humid January was 2023 at 83%, and the least humid was 1981 at 63%.
January receives about 6.6 kWh/m²/day of solar energy in Blenheim. The sunniest Januarys were 2019 and 2022 at 7.5 kWh/m²/day, and the cloudiest was 2007 at 5.8.
Average wind speed in Blenheim during January is 2.4 m/s. The windiest January was 1983 at 3 m/s, while the calmest was 2022 at 1.9 m/s.
Ranked against the other 11 months using 1981–2025 averages.
| Metric | 1980s | 1990s | 2000s | 2010s | 2020s | Change |
|---|---|---|---|---|---|---|
| Avg Temp | 16.6°C | 16.0°C | 16.6°C | 16.5°C | 16.3°C | -0.3°C |
| Avg High | 22.1°C | 21.1°C | 22.0°C | 21.8°C | 21.4°C | -0.7°C |
| Avg Low | 11.2°C | 10.9°C | 11.0°C | 11.3°C | 11.2°C | 0°C |
| Avg Rain | 67 mm | 66 mm | 48 mm | 67 mm | 44 mm | -22 mm |
January temperatures in Blenheim have stayed relatively stable across the record.
January has ranged from a record low of 4°C (1995) to a record high of 32.2°C (1981).
Rainfall in January is one of the drier months, averaging 59 mm, with a wettest year of 172 mm.
One of the best times to visit Blenheim
January is one of the best times to visit Blenheim. Expect days averaging 21.7°C and nights around 11.1°C (mean 16.4°C) — warmer than Blenheim's yearly average — with moderate rainfall (59 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 | 19.7°C | 14.9°C | 10.0°C | 26.0°C | 6.5°C | 83 mm | 76% | 2 m/s | 6.4 |
| 2024 | 22.6°C | 17.3°C | 11.9°C | 26.0°C | 6.9°C | 44 mm | 72% | 2.4 m/s | 7.3 |
| 2023 | 19.5°C | 15.7°C | 11.8°C | 22.9°C | 9.1°C | 87 mm | 83% | 2.2 m/s | 6.1 |
| 2022 | 22.5°C | 17.1°C | 11.7°C | 25.8°C | 8.7°C | 25 mm | 73% | 1.9 m/s | 7.5 |
| 2021 | 21.8°C | 16.4°C | 11.1°C | 31.1°C | 7.8°C | 19 mm | 71% | 2.5 m/s | 7 |
| 2020 | 22.5°C | 16.7°C | 10.9°C | 30.1°C | 6.3°C | 10 mm | 69% | 2.2 m/s | 7.1 |
| 2019 | 24.7°C | 18.8°C | 12.9°C | 31.8°C | 9.2°C | 17 mm | 67% | 2.4 m/s | 7.5 |
| 2018 🔥 | 23.3°C | 18.9°C | 14.5°C | 28.5°C | 8.8°C | 164 mm | 80% | 2 m/s | 6 |
| 2017 | 19.6°C | 14.6°C | 9.5°C | 23.4°C | 5.8°C | 67 mm | 75% | 2.9 m/s | 6.6 |
| 2016 | 22.0°C | 16.8°C | 11.6°C | 27.8°C | 6.3°C | 121 mm | 74% | 2.6 m/s | 6.2 |
| 2015 | 24.2°C | 18.0°C | 11.9°C | 28.4°C | 8.2°C | 9 mm | 66% | 2.1 m/s | 7.4 |
| 2014 | 20.0°C | 14.8°C | 9.6°C | 24.3°C | 6.5°C | 75 mm | 72% | 2.8 m/s | 6.5 |
| 2013 | 22.3°C | 16.5°C | 10.7°C | 28.4°C | 6.6°C | 80 mm | 66% | 2.7 m/s | 6.7 |
| 2012 | 19.5°C | 14.8°C | 10.1°C | 23.0°C | 5.9°C | 30 mm | 75% | 2.6 m/s | 6.6 |
| 2011 | 21.3°C | 16.1°C | 10.9°C | 25.8°C | 6.2°C | 51 mm | 72% | 2.8 m/s | 6.4 |
| 2010 | 21.3°C | 16.1°C | 10.9°C | 27.5°C | 7.0°C | 59 mm | 70% | 2.6 m/s | 6 |
| 2009 | 23.6°C | 17.4°C | 11.2°C | 31.6°C | 6.4°C | 14 mm | 65% | 2.3 m/s | 7.2 |
| 2008 | 23.5°C | 17.8°C | 12.1°C | 28.6°C | 6.8°C | 23 mm | 68% | 2.3 m/s | 7 |
| 2007 | 21.7°C | 16.4°C | 11.0°C | 27.4°C | 5.7°C | 56 mm | 73% | 2.3 m/s | 5.8 |
| 2006 | 22.6°C | 16.6°C | 10.5°C | 28.9°C | 6.2°C | 50 mm | 65% | 2.7 m/s | 6.7 |
| 2005 | 21.1°C | 15.8°C | 10.5°C | 26.1°C | 6.6°C | 54 mm | 74% | 2.2 m/s | 6.7 |
| 2004 | 23.8°C | 18.3°C | 12.8°C | 31.3°C | 7.9°C | 65 mm | 70% | 2.5 m/s | 6.3 |
| 2003 | 21.7°C | 15.9°C | 10.1°C | 25.4°C | 5.5°C | 39 mm | 68% | 2.5 m/s | 7 |
| 2002 | 20.0°C | 15.7°C | 11.5°C | 25.4°C | 7.1°C | 94 mm | 77% | 2.3 m/s | 5.9 |
| 2001 | 22.3°C | 16.2°C | 10.0°C | 27.7°C | 5.8°C | 17 mm | 63% | 2.3 m/s | 7.1 |
| 2000 | 20.2°C | 15.4°C | 10.6°C | 23.8°C | 7.2°C | 66 mm | 74% | 2.6 m/s | 5.9 |
| 1999 | 23.4°C | 18.0°C | 12.6°C | 29.8°C | 8.4°C | 43 mm | 70% | 2.5 m/s | 7 |
| 1998 | 23.5°C | 17.5°C | 11.5°C | 29.9°C | 4.6°C | 21 mm | 66% | 2.4 m/s | 6.5 |
| 1997 | 20.0°C | 14.8°C | 9.7°C | 23.5°C | 5.7°C | 65 mm | 72% | 2.1 m/s | 6.7 |
| 1996 | 20.3°C | 16.0°C | 11.7°C | 24.3°C | 5.6°C | 76 mm | 79% | 2.2 m/s | 6.5 |
| 1995 | 21.0°C | 15.8°C | 10.5°C | 25.3°C | 4.0°C | 111 mm | 72% | 2.4 m/s | 6.7 |
| 1994 | 20.5°C | 15.6°C | 10.7°C | 23.8°C | 5.9°C | 74 mm | 76% | 2.9 m/s | 6.4 |
| 1993 ❄️ | 18.7°C | 13.6°C | 8.5°C | 24.4°C | 5.2°C | 64 mm | 77% | 2.3 m/s | 6.6 |
| 1992 | 20.4°C | 15.6°C | 10.9°C | 24.1°C | 5.8°C | 83 mm | 76% | 2.2 m/s | 6.6 |
| 1991 | 20.7°C | 15.8°C | 10.8°C | 26.8°C | 7.2°C | 86 mm | 74% | 2.5 m/s | 6.1 |
| 1990 | 22.7°C | 17.2°C | 11.6°C | 29.6°C | 7.2°C | 33 mm | 66% | 2.3 m/s | 6.7 |
| 1989 | 22.3°C | 17.4°C | 12.5°C | 26.4°C | 7.4°C | 82 mm | 71% | 2.2 m/s | 6.2 |
| 1988 | 22.9°C | 17.0°C | 11.2°C | 28.8°C | 6.0°C | 13 mm | 67% | 2.2 m/s | 7.3 |
| 1987 | 22.3°C | 16.8°C | 11.3°C | 27.8°C | 7.0°C | 43 mm | 69% | 2.3 m/s | 6.9 |
| 1986 | 21.6°C | 16.9°C | 12.2°C | 26.8°C | 7.5°C | 166 mm | 78% | 2.1 m/s | 6.3 |
| 1985 🌧️ | 21.5°C | 16.8°C | 12.0°C | 26.1°C | 8.9°C | 172 mm | 74% | 2.5 m/s | 6.5 |
| 1984 | 19.8°C | 14.4°C | 9.0°C | 24.7°C | 4.5°C | 33 mm | 68% | 2.5 m/s | 6.4 |
| 1983 | 21.4°C | 15.2°C | 9.1°C | 27.1°C | 5.9°C | 46 mm | 64% | 3 m/s | — |
| 1982 | 22.6°C | 16.7°C | 10.8°C | 29.0°C | 7.2°C | 28 mm | 66% | 2.8 m/s | — |
| 1981 | 24.7°C | 18.6°C | 12.4°C | 32.2°C | 7.5°C | 19 mm | 63% | 2.3 m/s | — |
Actual recorded January data for each year, 1981–2025 — sourced from NASA POWER.
The average high in January is around 21.7°C with lows near 11.1°C (mean 16.4°C), based on 45 years of NASA POWER data.
January averages 59 mm of rainfall in Blenheim, one of the drier months. The wettest on record was 172 mm in 1985.
The hottest January reached 32.2°C in 1981. The coldest dipped to 4°C in 1995.
Comparing the earliest years on record (1981–1985) with the most recent (2021–2025), average January temperatures have held steady by about 0°C — but days and nights have moved in opposite directions. Overnight lows rose from 10.7°C to 11.3°C while daytime highs eased from 22°C to 21.2°C, narrowing the gap between day and night.
January is one of the warmer months of the year in Blenheim and one of the drier months, so plan for around 21.7°C daytime highs and 11.1°C at night.
Not quite — January is the 11th coolest month in Blenheim, averaging 16.4°C.
For January in Blenheim, pack light layers you can adjust through the day, with typical highs of 21.7°C and lows of 11.1°C. Bring an umbrella or light rain jacket too.
Relative humidity in January averages 71% — moderately humid.
Average wind speed in January is 2.4 m/s. The windiest January on record averaged 3 m/s (1983).
The wettest January on record was 1985 with 172 mm. On average, January sees 59 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 Blenheim behaves each January, 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 January specifically, along with year-by-year records and how the month has changed over the decades.
