July is one of the warmer months of the year in Siwan, with average highs near 38.7°C and lows around 25.5°C (mean 32.1°C). It is a relatively wet time of year, averaging 287 mm of rainfall and 75% relative humidity across the period.
July is one of the warmer months of the year in Siwan. Across 45 years of records, the warmest Julys in Siwan were 1982 and 1987 — when the month averaged 35.4°C — while the coldest was 1990 at 29.4°C. Typical July days reach 38.7°C with nights near 25.5°C. The long-term July temperature trend is broadly flat.
Ranked against the other 11 months using 1981–2025 averages.
| Metric | 1980s | 1990s | 2000s | 2010s | 2020s | Change |
|---|---|---|---|---|---|---|
| Avg Temp | 32.3°C | 32.4°C | 31.4°C | 32.2°C | 31.9°C | -0.4°C |
| Avg High | 39.4°C | 39.4°C | 37.4°C | 39.1°C | 37.7°C | -1.7°C |
| Avg Low | 25.2°C | 25.5°C | 25.5°C | 25.3°C | 26.2°C | +1°C |
| Avg Rain | 348 mm | 285 mm | 299 mm | 260 mm | 223 mm | -125 mm |
July temperatures in Siwan have stayed relatively stable across the record.
July has ranged from a record low of 24.2°C (1986) to a record high of 45.6°C (1987).
Rainfall in July is a relatively wet time of year, averaging 287 mm, with a wettest year of 585 mm.
Daytime highs and overnight lows have shifted differently — highs fell about 0.3°C per decade while lows rose 0.1°C per decade, narrowing the gap between day and night.
A quieter season to visit Siwan
If your dates are flexible, the more temperate months of November and February tend to be the most comfortable for visiting Siwan. That said, July — with days averaging 38.7°C and nights around 25.5°C (mean 32.1°C) and higher rainfall (287 mm) — can still be rewarding for travellers who don't mind the warmth, and often means fewer crowds.
| Year | High | Low | Avg | Rainfall | Humidity | Wind | Solar |
|---|---|---|---|---|---|---|---|
| 2025 | 40.2°C | 26.2°C | 33.2°C | 186 mm | 69% | 3.3 m/s | 5 |
| 2024 | 38.5°C | 26.9°C | 32.7°C | 251 mm | 77% | 2.4 m/s | 4.5 |
| 2023 | 38.9°C | 27.1°C | 33.0°C | 125 mm | 69% | 2.9 m/s | 4.7 |
| 2022 | 39.9°C | 25.8°C | 32.8°C | 133 mm | 69% | 3.1 m/s | 5.2 |
| 2021 | 34.7°C | 25.5°C | 30.1°C | 234 mm | 84% | 2.3 m/s | 4.4 |
| 2020 | 34.0°C | 25.4°C | 29.7°C | 406 mm | 87% | 2.3 m/s | 3.7 |
| 2019 | 40.5°C | 25.9°C | 33.2°C | 361 mm | 77% | 2.8 m/s | 4.3 |
| 2018 | 42.1°C | 25.6°C | 33.9°C | 207 mm | 63% | 3.4 m/s | 4.6 |
| 2017 | 36.7°C | 24.4°C | 30.6°C | 321 mm | 80% | 3 m/s | 4.5 |
| 2016 | 39.0°C | 26.0°C | 32.5°C | 284 mm | 75% | 2.8 m/s | 4.2 |
| 2015 | 40.9°C | 24.9°C | 32.9°C | 313 mm | 77% | 2.8 m/s | 5 |
| 2014 | 38.0°C | 26.0°C | 32.0°C | 220 mm | 76% | 2.2 m/s | 4.8 |
| 2013 | 36.0°C | 25.6°C | 30.8°C | 116 mm | 75% | 2.4 m/s | 5.2 |
| 2012 | 41.1°C | 24.8°C | 32.9°C | 361 mm | 75% | 2.6 m/s | 4.4 |
| 2011 | 35.0°C | 25.3°C | 30.2°C | 159 mm | 82% | 2.5 m/s | 5 |
| 2010 | 41.2°C | 24.3°C | 32.8°C | 263 mm | 71% | 3 m/s | 5 |
| 2009 | 39.7°C | 26.8°C | 33.2°C | 213 mm | 65% | 2.9 m/s | 5.4 |
| 2008 | 33.8°C | 25.5°C | 29.6°C | 465 mm | 88% | 2.3 m/s | 4.1 |
| 2007 | 36.9°C | 24.8°C | 30.8°C | 502 mm | 79% | 2.5 m/s | 3.4 |
| 2006 | 38.9°C | 25.4°C | 32.2°C | 343 mm | 79% | 2.9 m/s | 4.9 |
| 2005 | 38.5°C | 25.5°C | 32.0°C | 367 mm | 79% | 2.6 m/s | 5 |
| 2004 | 37.7°C | 25.1°C | 31.4°C | 247 mm | 82% | 3 m/s | 4.5 |
| 2003 | 36.6°C | 25.6°C | 31.1°C | 241 mm | 80% | 2.6 m/s | 5 |
| 2002 | 40.4°C | 26.3°C | 33.3°C | 217 mm | 66% | 2.2 m/s | 4.5 |
| 2001 | 35.3°C | 25.4°C | 30.4°C | 195 mm | 81% | 2.6 m/s | 5 |
| 2000 | 36.0°C | 24.7°C | 30.3°C | 203 mm | 81% | 2.4 m/s | 5 |
| 1999 | 39.6°C | 24.9°C | 32.2°C | 260 mm | 75% | 2.6 m/s | 4.7 |
| 1998 | 39.4°C | 25.8°C | 32.6°C | 305 mm | 80% | 2.6 m/s | 4.7 |
| 1997 | 38.5°C | 25.8°C | 32.1°C | 531 mm | 81% | 2.2 m/s | 5.3 |
| 1996 | 39.2°C | 24.3°C | 31.7°C | 248 mm | 76% | 2.4 m/s | 5 |
| 1995 | 39.7°C | 25.2°C | 32.4°C | 297 mm | 75% | 2.7 m/s | 5.3 |
| 1994 | 39.2°C | 25.5°C | 32.4°C | 211 mm | 70% | 3 m/s | 5.2 |
| 1993 | 39.7°C | 26.4°C | 33.1°C | 132 mm | 65% | 3 m/s | 5.2 |
| 1992 | 44.1°C | 25.5°C | 34.8°C | 199 mm | 65% | 2.6 m/s | 5 |
| 1991 | 40.6°C | 26.9°C | 33.7°C | 110 mm | 61% | 3.3 m/s | 4.8 |
| 1990 ❄️ | 34.1°C | 24.8°C | 29.4°C | 554 mm | 85% | 2.5 m/s | 4.8 |
| 1989 | 39.6°C | 24.5°C | 32.0°C | 313 mm | 73% | 2.4 m/s | 5 |
| 1988 | 37.1°C | 25.5°C | 31.3°C | 296 mm | 80% | 2.6 m/s | 4.6 |
| 1987 | 45.6°C | 25.1°C | 35.4°C | 416 mm | 78% | 2.3 m/s | 4.5 |
| 1986 | 36.5°C | 24.2°C | 30.4°C | 364 mm | 83% | 3.2 m/s | 5.3 |
| 1985 | 38.0°C | 24.5°C | 31.2°C | 497 mm | 78% | 2.6 m/s | 5 |
| 1984 | 34.3°C | 24.6°C | 29.5°C | 312 mm | 83% | 2.3 m/s | 4 |
| 1983 | 43.1°C | 26.4°C | 34.7°C | 166 mm | 59% | 2.1 m/s | — |
| 1982 🔥 | 44.8°C | 26.0°C | 35.4°C | 183 mm | 58% | 2.8 m/s | — |
| 1981 🌧️ | 36.0°C | 25.7°C | 30.8°C | 585 mm | 85% | 2.8 m/s | — |
Actual recorded July data for each year, 1981–2025 — sourced from NASA POWER.
The average high in July is around 38.7°C with lows near 25.5°C (mean 32.1°C), based on 45 years of NASA POWER data.
July averages 287 mm of rainfall in Siwan, a relatively wet time of year. The wettest on record was 585 mm in 1981.
The hottest July reached 45.6°C in 1987. The coldest dipped to 24.2°C in 1986.
Comparing the earliest years on record (1981–1985) with the most recent (2021–2025), average July temperatures have risen by about 0.1°C. Daytime highs moved from 39.2°C to 38.4°C and overnight lows from 25.4°C to 26.3°C over the same span.
July is one of the warmer months of the year in Siwan and a relatively wet time of year, so plan for around 38.7°C daytime highs and 25.5°C at night.
Not quite — July is the 10th coolest month in Siwan, averaging 32.1°C.
For July in Siwan, pack light, breathable clothing and sun protection, with typical highs of 38.7°C and lows of 25.5°C. Bring an umbrella or light rain jacket too.
Relative humidity in July averages 75% — quite humid.
Average wind speed in July is 2.7 m/s. The windiest July on record averaged 3.4 m/s (2018).
The wettest July on record was 1981 with 585 mm. On average, July sees 287 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 July, 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 July specifically, along with year-by-year records and how the month has changed over the decades.
