July is one of the warmer months of the year in Llanelli, with average highs near 17.8°C and lows around 14.3°C (mean 16.1°C). It is one of the drier months, averaging 75 mm of rainfall and 85% relative humidity across the period.
July is one of the warmer months of the year in Llanelli. Across 45 years of records, the warmest Julys in Llanelli were 1983 and 2006 — when the month averaged 17.9°C — while the coldest was 1988 at 14.4°C. Typical July days reach 17.8°C with nights near 14.3°C. The long-term trend is warming, about 0.2°C per decade.
July is one of the drier months in Llanelli, averaging 75 mm of rainfall. The wettest July on record was 2009 with 200 mm, while the driest was 1999 at 21 mm.
Relative humidity in Llanelli during July averages 85%. The most humid July was 1991 at 88%, and the least humid was 1990 at 81%.
July receives about 5.5 kWh/m²/day of solar energy in Llanelli. The sunniest July was 2013 at 6.5 kWh/m²/day, and the cloudiest was 2003 at 4.6.
Average wind speed in Llanelli during July is 4 m/s. The windiest July was 1988 at 5.8 m/s, while the calmest was 1983 at 2.6 m/s.
Ranked against the other 11 months using 1981–2025 averages.
| Metric | 1980s | 1990s | 2000s | 2010s | 2020s | Change |
|---|---|---|---|---|---|---|
| Avg Temp | 15.9°C | 15.9°C | 15.9°C | 16.3°C | 16.6°C | +0.7°C |
| Avg High | 17.8°C | 17.7°C | 17.5°C | 18.1°C | 18.2°C | +0.4°C |
| Avg Low | 14.0°C | 14.0°C | 14.2°C | 14.6°C | 14.9°C | +0.9°C |
| Avg Rain | 57 mm | 59 mm | 100 mm | 76 mm | 89 mm | +32 mm |
July temperatures in Llanelli have risen by about 0.6°C between 1981–1985 and 2021–2025.
July has ranged from a record low of 10°C (1997) to a record high of 25.5°C (2025).
Rainfall in July is one of the drier months, averaging 75 mm, with a wettest year of 200 mm.
One of the best times to visit Llanelli
July is one of the best times to visit Llanelli. Expect days averaging 17.8°C and nights around 14.3°C (mean 16.1°C) — warmer than Llanelli's yearly average — with moderate rainfall (75 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 | 19.2°C | 17.5°C | 15.9°C | 25.5°C | 14.0°C | 52 mm | 84% | 3.8 m/s | 5.7 |
| 2024 | 17.6°C | 15.9°C | 14.2°C | 21.9°C | 12.0°C | 104 mm | 85% | 3.9 m/s | 5.1 |
| 2023 | 17.6°C | 16.3°C | 14.9°C | 20.3°C | 13.7°C | 148 mm | 85% | 5.5 m/s | 5.3 |
| 2022 | 19.0°C | 17.0°C | 15.0°C | 24.5°C | 13.0°C | 32 mm | 83% | 3.7 m/s | 5.8 |
| 2021 | 19.2°C | 17.2°C | 15.2°C | 25.2°C | 12.4°C | 105 mm | 85% | 3.3 m/s | 5.6 |
| 2020 | 16.9°C | 15.4°C | 14.0°C | 20.4°C | 11.9°C | 93 mm | 86% | 4.9 m/s | 5.4 |
| 2019 | 18.7°C | 16.8°C | 14.9°C | 22.9°C | 12.0°C | 44 mm | 85% | 3.5 m/s | 5.9 |
| 2018 | 19.8°C | 17.7°C | 15.6°C | 22.7°C | 14.2°C | 51 mm | 83% | 3 m/s | 6.2 |
| 2017 | 17.8°C | 16.1°C | 14.5°C | 21.1°C | 13.0°C | 123 mm | 85% | 4.3 m/s | 5.3 |
| 2016 | 17.6°C | 16.0°C | 14.4°C | 23.5°C | 12.0°C | 56 mm | 87% | 4.5 m/s | 5.3 |
| 2015 | 16.9°C | 15.4°C | 13.9°C | 19.3°C | 11.7°C | 107 mm | 84% | 5 m/s | 5.4 |
| 2014 | 18.9°C | 17.1°C | 15.3°C | 23.3°C | 13.4°C | 35 mm | 84% | 3.6 m/s | 5.7 |
| 2013 | 19.4°C | 17.2°C | 15.0°C | 23.4°C | 12.1°C | 43 mm | 85% | 3.1 m/s | 6.5 |
| 2012 | 16.5°C | 15.0°C | 13.5°C | 21.6°C | 11.6°C | 115 mm | 86% | 4.4 m/s | 5.2 |
| 2011 | 17.2°C | 15.4°C | 13.7°C | 19.6°C | 12.0°C | 74 mm | 83% | 3.8 m/s | 5.6 |
| 2010 | 17.7°C | 16.2°C | 14.7°C | 19.4°C | 13.2°C | 107 mm | 86% | 4.5 m/s | 5 |
| 2009 🌧️ | 17.3°C | 16.0°C | 14.6°C | 23.2°C | 13.3°C | 200 mm | 86% | 5.5 m/s | 5.2 |
| 2008 | 17.2°C | 15.6°C | 14.0°C | 21.8°C | 11.7°C | 127 mm | 87% | 4.8 m/s | 5.2 |
| 2007 | 16.5°C | 15.2°C | 13.9°C | 18.0°C | 12.5°C | 158 mm | 85% | 5.2 m/s | 5.5 |
| 2006 | 20.0°C | 17.9°C | 15.8°C | 24.2°C | 13.4°C | 38 mm | 84% | 3.3 m/s | 5.8 |
| 2005 | 18.0°C | 16.2°C | 14.4°C | 24.3°C | 11.9°C | 83 mm | 86% | 3.7 m/s | 5.3 |
| 2004 | 16.6°C | 15.1°C | 13.6°C | 19.0°C | 11.6°C | 61 mm | 86% | 4.2 m/s | 5.3 |
| 2003 | 18.0°C | 16.3°C | 14.7°C | 24.1°C | 12.3°C | 109 mm | 86% | 4.2 m/s | 4.6 |
| 2002 | 16.4°C | 14.8°C | 13.3°C | 19.2°C | 11.4°C | 65 mm | 87% | 3.8 m/s | 5.3 |
| 2001 | 17.7°C | 16.0°C | 14.3°C | 23.4°C | 11.8°C | 92 mm | 85% | 3.7 m/s | 5.2 |
| 2000 | 17.3°C | 15.5°C | 13.8°C | 20.6°C | 11.5°C | 65 mm | 86% | 3.8 m/s | 5.9 |
| 1999 | 18.5°C | 16.4°C | 14.4°C | 21.8°C | 12.5°C | 21 mm | 85% | 3.8 m/s | 5.9 |
| 1998 | 16.6°C | 15.2°C | 13.8°C | 18.3°C | 12.3°C | 72 mm | 86% | 5.1 m/s | 5.1 |
| 1997 | 17.7°C | 15.8°C | 13.9°C | 22.0°C | 10.0°C | 36 mm | 85% | 3.4 m/s | 5.5 |
| 1996 | 17.3°C | 15.5°C | 13.6°C | 20.7°C | 10.7°C | 48 mm | 84% | 3.9 m/s | 6 |
| 1995 | 18.7°C | 16.8°C | 14.8°C | 24.1°C | 12.0°C | 51 mm | 86% | 3.7 m/s | 5.5 |
| 1994 | 17.8°C | 15.8°C | 13.9°C | 21.3°C | 12.4°C | 53 mm | 85% | 3.2 m/s | 5.4 |
| 1993 | 16.3°C | 14.9°C | 13.4°C | 17.9°C | 10.9°C | 101 mm | 86% | 4.9 m/s | 5.4 |
| 1992 | 17.9°C | 16.1°C | 14.2°C | 20.4°C | 12.3°C | 82 mm | 85% | 4 m/s | 5.2 |
| 1991 | 17.4°C | 15.8°C | 14.1°C | 21.5°C | 12.3°C | 83 mm | 88% | 4.4 m/s | 5 |
| 1990 | 18.9°C | 16.5°C | 14.2°C | 23.9°C | 11.2°C | 45 mm | 81% | 4.3 m/s | 6.4 |
| 1989 | 19.4°C | 17.2°C | 15.0°C | 22.5°C | 12.7°C | 41 mm | 84% | 3.4 m/s | 5.9 |
| 1988 ❄️ | 15.6°C | 14.4°C | 13.1°C | 17.2°C | 11.8°C | 153 mm | 86% | 5.8 m/s | 5 |
| 1987 | 17.5°C | 15.7°C | 13.9°C | 22.1°C | 11.9°C | 48 mm | 84% | 3.6 m/s | 5.3 |
| 1986 | 16.5°C | 14.9°C | 13.3°C | 18.9°C | 11.3°C | 53 mm | 87% | 3.8 m/s | 4.8 |
| 1985 | 17.1°C | 15.4°C | 13.7°C | 22.2°C | 12.0°C | 69 mm | 85% | 4 m/s | 5.1 |
| 1984 | 18.6°C | 16.3°C | 13.9°C | 22.1°C | 10.7°C | 32 mm | 81% | 3.4 m/s | 6 |
| 1983 🔥 | 20.5°C | 17.9°C | 15.3°C | 25.4°C | 10.7°C | 24 mm | 84% | 2.6 m/s | — |
| 1982 | 18.2°C | 16.1°C | 14.1°C | 21.0°C | 12.3°C | 53 mm | 84% | 3.3 m/s | — |
| 1981 | 16.7°C | 15.2°C | 13.7°C | 20.3°C | 12.2°C | 43 mm | 86% | 4.4 m/s | — |
Actual recorded July data for each year, 1981–2025 — sourced from NASA POWER.
The average high in July is around 17.8°C with lows near 14.3°C (mean 16.1°C), based on 45 years of NASA POWER data.
July averages 75 mm of rainfall in Llanelli, one of the drier months. The wettest on record was 200 mm in 2009.
The hottest July reached 25.5°C in 2025. The coldest dipped to 10°C in 1997.
Comparing the earliest years on record (1981–1985) with the most recent (2021–2025), average July temperatures have risen by about 0.6°C. Daytime highs moved from 18.2°C to 18.5°C and overnight lows from 14.1°C to 15°C over the same span.
July is one of the warmer months of the year in Llanelli and one of the drier months, so plan for around 17.8°C daytime highs and 14.3°C at night.
Not quite — July is the 11th coolest month in Llanelli, averaging 16.1°C.
For July in Llanelli, pack light layers you can adjust through the day, with typical highs of 17.8°C and lows of 14.3°C. Bring an umbrella or light rain jacket too.
Relative humidity in July averages 85% — quite humid.
Average wind speed in July is 4 m/s. The windiest July on record averaged 5.8 m/s (1988).
The wettest July on record was 2009 with 200 mm. On average, July sees 75 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 Llanelli 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.
