April is one of the cooler months of the year in Letchworth, with average highs near 13.3°C and lows around 3.8°C (mean 8.6°C). It is about average for rainfall, averaging 47 mm of rainfall and 81% relative humidity across the period.
April is one of the cooler months of the year in Letchworth. Across 45 years of records, the warmest April in Letchworth was 2011 — when the month averaged 11.9°C — while the coldest was 1986 at 5.5°C. Typical April days reach 13.3°C with nights near 3.8°C. The long-term trend is warming, about 0.4°C per decade.
April is about average for rainfall in Letchworth, averaging 47 mm of rainfall. The wettest April on record was 2000 with 119 mm, while the driest was 2007 at 3 mm.
Relative humidity in Letchworth during April averages 81%. The most humid April was 2001 at 86%, and the least humid was 1997 at 76%.
April receives about 3.9 kWh/m²/day of solar energy in Letchworth. The sunniest April was 2025 at 4.9 kWh/m²/day, and the cloudiest were 1993 and 1998 at 3.2.
Average wind speed in Letchworth during April is 3.2 m/s. The windiest April was 1994 at 4.2 m/s, while the calmest were 2009, 2021 and 2025 at 2.7 m/s.
Ranked against the other 11 months using 1981–2025 averages.
| Metric | 1980s | 1990s | 2000s | 2010s | 2020s | Change |
|---|---|---|---|---|---|---|
| Avg Temp | 7.5°C | 8.4°C | 9.0°C | 8.9°C | 8.9°C | +1.4°C |
| Avg High | 12.1°C | 13.0°C | 13.6°C | 13.8°C | 14.1°C | +2°C |
| Avg Low | 3.0°C | 3.9°C | 4.3°C | 4.0°C | 3.7°C | +0.7°C |
| Avg Rain | 54 mm | 52 mm | 50 mm | 40 mm | 34 mm | -20 mm |
April temperatures in Letchworth have risen by about 1.1°C between 1981–1985 and 2021–2025.
April has ranged from a record low of -4.2°C (1996) to a record high of 25.4°C (2018).
Rainfall in April is about average for rainfall, averaging 47 mm, with a wettest year of 119 mm.
Daytime highs and overnight lows have shifted differently — highs rose about 0.5°C per decade while lows rose 0.2°C per decade, widening the gap between day and night.
A good time to visit Letchworth
April is a good time to visit Letchworth, with days averaging 13.3°C and nights around 3.8°C (mean 8.6°C, cooler than Letchworth's yearly average) and moderate rainfall. July and August 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 | 16.4°C | 10.6°C | 4.8°C | 22.9°C | 1.5°C | 23 mm | 78% | 2.7 m/s | 4.9 |
| 2024 | 13.5°C | 9.4°C | 5.3°C | 19.2°C | 0.3°C | 65 mm | 82% | 4.1 m/s | 3.8 |
| 2023 | 13.5°C | 8.6°C | 3.7°C | 17.7°C | -1.3°C | 54 mm | 81% | 3.2 m/s | 3.9 |
| 2022 | 14.3°C | 9.2°C | 4.1°C | 19.9°C | -2.8°C | 17 mm | 78% | 3.4 m/s | 4.3 |
| 2021 | 11.2°C | 5.7°C | 0.2°C | 15.5°C | -3.5°C | 7 mm | 77% | 2.7 m/s | 4.6 |
| 2020 | 15.8°C | 10.1°C | 4.3°C | 21.9°C | -0.6°C | 35 mm | 78% | 2.9 m/s | 4.8 |
| 2019 | 14.4°C | 9.0°C | 3.5°C | 21.8°C | -1.9°C | 16 mm | 79% | 3 m/s | 4 |
| 2018 | 14.0°C | 10.0°C | 6.0°C | 25.4°C | 1.0°C | 89 mm | 85% | 3.4 m/s | 3.3 |
| 2017 | 13.9°C | 8.8°C | 3.7°C | 22.0°C | -1.2°C | 16 mm | 79% | 2.9 m/s | 4.3 |
| 2016 | 11.7°C | 7.2°C | 2.7°C | 15.6°C | -0.8°C | 53 mm | 81% | 3.1 m/s | 4.1 |
| 2015 | 14.3°C | 8.9°C | 3.5°C | 21.1°C | 0.6°C | 27 mm | 79% | 2.9 m/s | 4.7 |
| 2014 | 15.1°C | 10.3°C | 5.5°C | 18.2°C | 0.5°C | 34 mm | 83% | 3 m/s | 3.8 |
| 2013 | 11.6°C | 7.0°C | 2.4°C | 19.8°C | -3.2°C | 32 mm | 81% | 3.7 m/s | 4.1 |
| 2012 | 11.6°C | 7.3°C | 3.0°C | 16.9°C | -3.5°C | 107 mm | 82% | 3.4 m/s | 3.6 |
| 2011 🔥 | 17.6°C | 11.9°C | 6.3°C | 24.2°C | 3.1°C | 8 mm | 78% | 2.9 m/s | 4.6 |
| 2010 | 14.2°C | 9.0°C | 3.7°C | 18.9°C | 0.1°C | 20 mm | 79% | 2.9 m/s | 4.5 |
| 2009 | 15.4°C | 10.2°C | 5.1°C | 18.7°C | 1.9°C | 32 mm | 82% | 2.7 m/s | 4.1 |
| 2008 | 12.2°C | 7.9°C | 3.7°C | 19.4°C | -1.9°C | 47 mm | 82% | 3.3 m/s | 3.9 |
| 2007 | 17.2°C | 11.4°C | 5.7°C | 21.8°C | 0.6°C | 3 mm | 79% | 2.8 m/s | 4.7 |
| 2006 | 12.8°C | 8.5°C | 4.1°C | 16.7°C | -2.7°C | 36 mm | 81% | 3.2 m/s | 3.7 |
| 2005 | 13.7°C | 9.1°C | 4.5°C | 19.8°C | -1.9°C | 41 mm | 82% | 3 m/s | 3.7 |
| 2004 | 13.9°C | 9.3°C | 4.7°C | 20.7°C | 0.5°C | 76 mm | 83% | 3 m/s | 3.6 |
| 2003 | 13.9°C | 8.9°C | 3.8°C | 22.5°C | -2.9°C | 33 mm | 82% | 3.3 m/s | 3.9 |
| 2002 | 14.0°C | 9.2°C | 4.3°C | 20.2°C | -0.8°C | 38 mm | 80% | 3.4 m/s | 4.3 |
| 2001 | 11.0°C | 7.1°C | 3.1°C | 17.9°C | -1.5°C | 78 mm | 86% | 3.6 m/s | 3.3 |
| 2000 🌧️ | 12.2°C | 8.2°C | 4.2°C | 17.3°C | -2.6°C | 119 mm | 85% | 3.3 m/s | 3.3 |
| 1999 | 13.4°C | 9.1°C | 4.9°C | 18.5°C | -1.7°C | 53 mm | 83% | 3.3 m/s | 3.6 |
| 1998 | 11.4°C | 7.9°C | 4.4°C | 19.3°C | -0.8°C | 108 mm | 85% | 3.4 m/s | 3.2 |
| 1997 | 14.1°C | 8.7°C | 3.3°C | 18.4°C | -1.9°C | 21 mm | 76% | 3 m/s | 4.2 |
| 1996 | 12.9°C | 8.1°C | 3.3°C | 20.0°C | -4.2°C | 29 mm | 81% | 2.8 m/s | 3.7 |
| 1995 | 13.8°C | 8.8°C | 3.9°C | 18.8°C | -2.6°C | 26 mm | 81% | 3.2 m/s | 3.9 |
| 1994 | 11.8°C | 7.7°C | 3.6°C | 21.4°C | 0.0°C | 66 mm | 82% | 4.2 m/s | 3.8 |
| 1993 | 13.9°C | 9.5°C | 5.2°C | 23.0°C | 1.0°C | 83 mm | 83% | 3.4 m/s | 3.2 |
| 1992 | 13.0°C | 8.5°C | 4.0°C | 19.1°C | -0.4°C | 43 mm | 79% | 3.8 m/s | 3.4 |
| 1991 | 12.6°C | 8.1°C | 3.5°C | 20.5°C | -1.0°C | 56 mm | 79% | 4.1 m/s | 3.7 |
| 1990 | 13.1°C | 7.9°C | 2.7°C | 21.2°C | -3.3°C | 38 mm | 78% | 3.4 m/s | 4.4 |
| 1989 | 10.2°C | 6.2°C | 2.3°C | 14.6°C | -2.5°C | 78 mm | 82% | 3.4 m/s | 3.3 |
| 1988 | 12.7°C | 7.9°C | 3.0°C | 19.1°C | -2.7°C | 39 mm | 83% | 3 m/s | 3.7 |
| 1987 | 14.9°C | 10.1°C | 5.3°C | 21.0°C | 1.6°C | 53 mm | 84% | 3.1 m/s | 3.6 |
| 1986 ❄️ | 9.5°C | 5.5°C | 1.4°C | 15.8°C | -3.0°C | 71 mm | 83% | 3.5 m/s | 3.4 |
| 1985 | 12.3°C | 8.0°C | 3.6°C | 18.8°C | -2.9°C | 47 mm | 82% | 4 m/s | 3.6 |
| 1984 | 12.8°C | 7.4°C | 1.9°C | 20.5°C | -3.6°C | 13 mm | 79% | 2.8 m/s | 4.5 |
| 1983 | 10.9°C | 6.7°C | 2.5°C | 16.3°C | -1.9°C | 96 mm | 85% | 3.4 m/s | — |
| 1982 | 12.9°C | 8.2°C | 3.5°C | 16.0°C | -2.0°C | 23 mm | 81% | 3 m/s | — |
| 1981 | 12.4°C | 7.9°C | 3.4°C | 18.9°C | -0.9°C | 64 mm | 82% | 3.4 m/s | — |
Actual recorded April data for each year, 1981–2025 — sourced from NASA POWER.
The average high in April is around 13.3°C with lows near 3.8°C (mean 8.6°C), based on 45 years of NASA POWER data.
April averages 47 mm of rainfall in Letchworth, about average for rainfall. The wettest on record was 119 mm in 2000.
The hottest April reached 25.4°C in 2018. The coldest dipped to -4.2°C in 1996.
Comparing the earliest years on record (1981–1985) with the most recent (2021–2025), average April temperatures have risen by about 1.1°C. Daytime highs moved from 12.3°C to 13.8°C and overnight lows from 3°C to 3.6°C over the same span.
April is one of the cooler months of the year in Letchworth and about average for rainfall, so plan for around 13.3°C daytime highs and 3.8°C at night.
Not quite — April is the 6th coolest month in Letchworth, averaging 8.6°C.
For April in Letchworth, pack warm layers and a jacket for chilly mornings, with typical highs of 13.3°C and lows of 3.8°C.
Relative humidity in April averages 81% — quite humid.
Average wind speed in April is 3.2 m/s. The windiest April on record averaged 4.2 m/s (1994).
The wettest April on record was 2000 with 119 mm. On average, April sees 47 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 Letchworth 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.
