April is one of the warmer months of the year in Siwan, with average highs near 44.2°C and lows around 18.7°C (mean 31.5°C). It is one of the drier months, averaging 13 mm of rainfall and 23% relative humidity across the period.
April is one of the warmer months of the year in Siwan. Across 45 years of records, the warmest April in Siwan was 2016 — when the month averaged 33.7°C — while the coldest was 1996 at 29.3°C. Typical April days reach 44.2°C with nights near 18.7°C. The long-term trend is warming, about 0.2°C per decade.
Ranked against the other 11 months using 1981–2025 averages.
| Metric | 1980s | 1990s | 2000s | 2010s | 2020s | Change |
|---|---|---|---|---|---|---|
| Avg Temp | 31.2°C | 31.0°C | 31.7°C | 31.9°C | 31.7°C | +0.5°C |
| Avg High | 44.2°C | 44.5°C | 44.5°C | 43.8°C | 44.2°C | 0°C |
| Avg Low | 18.2°C | 17.6°C | 18.9°C | 20.0°C | 19.2°C | +1°C |
| Avg Rain | 16 mm | 6 mm | 15 mm | 16 mm | 14 mm | -2 mm |
April temperatures in Siwan have risen by about 0.6°C between 1981–1985 and 2021–2025.
April has ranged from a record low of 14.3°C (1988) to a record high of 47.1°C (1999).
Rainfall in April is one of the drier months, averaging 13 mm, with a wettest year of 59 mm.
Daytime highs and overnight lows have shifted differently — highs fell about 0.1°C per decade while lows rose 0.5°C per decade, narrowing the gap between day and night.
A good time to visit Siwan
April is a good time to visit Siwan, with days averaging 44.2°C and nights around 18.7°C (mean 31.5°C, warmer than Siwan's yearly average) and low rainfall. November and February are marginally more temperate, but April still suits most travellers.
| Year | High | Low | Avg | Rainfall | Humidity | Wind | Solar |
|---|---|---|---|---|---|---|---|
| 2025 | 45.3°C | 18.3°C | 31.8°C | 27 mm | 31% | 2.4 m/s | 5.6 |
| 2024 | 44.8°C | 21.3°C | 33.0°C | 1 mm | 20% | 3.5 m/s | 6.4 |
| 2023 | 44.6°C | 19.1°C | 31.8°C | 15 mm | 29% | 2.7 m/s | 6.1 |
| 2022 | 44.9°C | 21.8°C | 33.3°C | 4 mm | 24% | 2.3 m/s | 6.2 |
| 2021 | 43.7°C | 17.8°C | 30.8°C | 8 mm | 16% | 2.3 m/s | 6.3 |
| 2020 | 41.9°C | 17.0°C | 29.4°C | 29 mm | 35% | 2.2 m/s | 6.2 |
| 2019 | 45.9°C | 19.9°C | 32.9°C | 15 mm | 28% | 2.2 m/s | 6.1 |
| 2018 | 43.2°C | 21.3°C | 32.2°C | 49 mm | 32% | 2.4 m/s | 5.9 |
| 2017 | 43.9°C | 19.8°C | 31.8°C | 5 mm | 24% | 2.4 m/s | 6.1 |
| 2016 🔥 | 45.1°C | 22.3°C | 33.7°C | 0 mm | 17% | 3.1 m/s | 6.6 |
| 2015 | 42.7°C | 19.3°C | 31.0°C | 25 mm | 37% | 2.2 m/s | 5.9 |
| 2014 | 44.3°C | 18.4°C | 31.3°C | 0 mm | 20% | 2.4 m/s | 7 |
| 2013 | 43.8°C | 18.1°C | 31.0°C | 20 mm | 30% | 2.4 m/s | 6.4 |
| 2012 | 43.0°C | 20.2°C | 31.6°C | 12 mm | 25% | 2.4 m/s | 6.6 |
| 2011 | 41.2°C | 19.4°C | 30.3°C | 31 mm | 30% | 1.9 m/s | 6.3 |
| 2010 | 45.4°C | 21.0°C | 33.2°C | 0 mm | 16% | 2.3 m/s | 6.7 |
| 2009 | 44.0°C | 18.4°C | 31.2°C | 0 mm | 17% | 2.2 m/s | 6.9 |
| 2008 | 44.3°C | 17.7°C | 31.0°C | 29 mm | 29% | 1.8 m/s | 6.9 |
| 2007 | 42.9°C | 17.3°C | 30.1°C | 17 mm | 30% | 2 m/s | 6.4 |
| 2006 | 42.9°C | 20.3°C | 31.6°C | 17 mm | 27% | 2 m/s | 6.4 |
| 2005 | 44.1°C | 16.7°C | 30.4°C | 7 mm | 19% | 1.9 m/s | 6.5 |
| 2004 | 45.3°C | 20.7°C | 33.0°C | 33 mm | 28% | 2.3 m/s | 6.1 |
| 2003 | 45.5°C | 19.7°C | 32.6°C | 17 mm | 20% | 2.2 m/s | 6.8 |
| 2002 | 45.0°C | 19.3°C | 32.2°C | 5 mm | 24% | 2.2 m/s | 6.4 |
| 2001 | 46.2°C | 19.8°C | 33.0°C | 11 mm | 19% | 2.1 m/s | 6.6 |
| 2000 | 44.6°C | 18.6°C | 31.6°C | 17 mm | 19% | 2.4 m/s | 6.6 |
| 1999 | 47.1°C | 18.6°C | 32.8°C | 0 mm | 11% | 2.3 m/s | 7.3 |
| 1998 | 43.7°C | 18.6°C | 31.1°C | 6 mm | 24% | 2 m/s | 6.6 |
| 1997 | 42.2°C | 17.3°C | 29.7°C | 20 mm | 28% | 2.1 m/s | 6.5 |
| 1996 ❄️ | 43.3°C | 15.4°C | 29.3°C | 9 mm | 18% | 2.1 m/s | 6.4 |
| 1995 | 45.5°C | 17.2°C | 31.3°C | 0 mm | 14% | 2.5 m/s | 7 |
| 1994 | 43.2°C | 19.3°C | 31.3°C | 11 mm | 19% | 2.2 m/s | 6.7 |
| 1993 | 44.5°C | 16.7°C | 30.6°C | 7 mm | 23% | 2.4 m/s | 6.5 |
| 1992 | 44.5°C | 19.3°C | 31.9°C | 0 mm | 16% | 3.2 m/s | 6.7 |
| 1991 | 45.0°C | 17.6°C | 31.3°C | 0 mm | 16% | 2.3 m/s | 6.7 |
| 1990 | 45.6°C | 15.7°C | 30.6°C | 2 mm | 17% | 2.9 m/s | 7 |
| 1989 | 44.9°C | 15.5°C | 30.2°C | 0 mm | 12% | 3.1 m/s | 7.3 |
| 1988 | 44.8°C | 14.3°C | 29.6°C | 13 mm | 20% | 2 m/s | 6.2 |
| 1987 | 43.5°C | 19.7°C | 31.6°C | 19 mm | 20% | 2.8 m/s | 6.7 |
| 1986 | 43.7°C | 20.0°C | 31.9°C | 22 mm | 19% | 2.2 m/s | 7.2 |
| 1985 | 45.2°C | 21.0°C | 33.1°C | 0 mm | 19% | 2.8 m/s | 7.1 |
| 1984 | 44.9°C | 21.4°C | 33.2°C | 2 mm | 17% | 2 m/s | 6.6 |
| 1983 | 45.2°C | 17.9°C | 31.6°C | 10 mm | 27% | 2.7 m/s | — |
| 1982 🌧️ | 42.3°C | 17.6°C | 30.0°C | 59 mm | 32% | 2.3 m/s | — |
| 1981 | 43.0°C | 16.5°C | 29.7°C | 23 mm | 27% | 2.3 m/s | — |
Actual recorded April data for each year, 1981–2025 — sourced from NASA POWER.
The average high in April is around 44.2°C with lows near 18.7°C (mean 31.5°C), based on 45 years of NASA POWER data.
April averages 13 mm of rainfall in Siwan, one of the drier months. The wettest on record was 59 mm in 1982.
The hottest April reached 47.1°C in 1999. The coldest dipped to 14.3°C in 1988.
Comparing the earliest years on record (1981–1985) with the most recent (2021–2025), average April temperatures have risen by about 0.6°C. Daytime highs moved from 44.1°C to 44.7°C and overnight lows from 18.9°C to 19.7°C over the same span.
April is one of the warmer months of the year in Siwan and one of the drier months, so plan for around 44.2°C daytime highs and 18.7°C at night.
Not quite — April is the 9th coolest month in Siwan, averaging 31.5°C.
For April in Siwan, pack light, breathable clothing and sun protection, with typical highs of 44.2°C and lows of 18.7°C.
Relative humidity in April averages 23% — relatively dry.
Average wind speed in April is 2.4 m/s. The windiest April on record averaged 3.5 m/s (2024).
The wettest April on record was 1982 with 59 mm. On average, April sees 13 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 Siwan 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.
