Climate averages 1991–2020
Derry weather
in August.
A mild, wet month: the 2nd warmest and the wettest of the year.
Long-term climate patterns, not a forecast for a particular trip.
August is a mild month in Derry: daytime highs average 17.1°C and nights cool to about 11.9°C. By daytime temperature it is the 2nd warmest of the 12 months.
Expect about 94 mm of rain on roughly 17 days, which makes August a wet month (the wettest month of the year). Daylight, from sunrise to sunset, lasts about 14 h 59 min on an average August day.
The nearest other city in this atlas is Lisburn (97 km away). In August its highs average 17.4°C, about as warm as Derry, with 81 mm of rain.
Among the 143 cities listed in the United Kingdom, Derry ranks 141st of 143 for the warmest August highs and 132nd of 143 for the driest August (rainfall, lowest first). The mean August high of those 143 cities is 19.7°C; Derry is 2.6°C cooler than that mean.
From August to September, average highs fall by 1.7°C to 15.4°C, and monthly rainfall falls from 94 mm to 75 mm.
The annual picture
August in context
Monthly rainfall
Average total · mmAverages from hourly ERA5 reanalysis data. Actual weather varies from year to year. How these numbers are calculated
Every month, side by side
Derry climate table
| Month | Average highHigh / low | Average low | Rainfall mm/month | Rain days ≥1 mm/day | Daylight hours/dayDaylight h/day |
|---|---|---|---|---|---|
| January | 7.1°C3.0°C | 3.0°C | 87 | 16.4 | 7.88 h |
| February | 7.5°C3.0°C | 3.0°C | 76 | 15.1 | 9.610 h |
| March | 9.0°C3.7°C | 3.7°C | 75 | 15.6 | 11.812 h |
| April | 11.1°C5.1°C | 5.1°C | 74 | 15.4 | 14.114 h |
| May | 13.8°C7.6°C | 7.6°C | 78 | 15.1 | 16.116 h |
| June | 15.9°C10.2°C | 10.2°C | 87 | 15.5 | 17.317 h |
| July | 17.3°C11.9°C | 11.9°C | 93 | 16.8 | 16.817 h |
| August, selected | 17.1°C11.9°C | 11.9°C | 94 | 16.7 | 15.015 h |
| September | 15.4°C10.4°C | 10.4°C | 75 | 14.2 | 12.813 h |
| October | 12.3°C8.0°C | 8.0°C | 88 | 15.5 | 10.511 h |
| November | 9.3°C5.4°C | 5.4°C | 90 | 16.6 | 8.58 h |
| December | 7.4°C3.4°C | 3.4°C | 90 | 15.8 | 7.37 h |
Rainfall is the average of the 30 separate monthly totals. A rain day is a local calendar day with at least 1 mm of precipitation. Daylight is the calculated sunrise-to-sunset length, not measured sunshine.
Compare places
August in nearby cities
- Lisburn in AugustUnited Kingdom · 97 kmHigh 17.4°C · Low 12.1°C · 81 mm rain
- Belfast in AugustUnited Kingdom · 99 kmHigh 17.3°C · Low 12.6°C · 81 mm rain
- Dublin in AugustIreland · 198 kmHigh 18.6°C · Low 12.8°C · 78 mm rain
- Tallaght in AugustIreland · 200 kmHigh 18.2°C · Low 12.3°C · 78 mm rain
- Paisley in AugustUnited Kingdom · 204 kmHigh 17.2°C · Low 11.1°C · 105 mm rain
- Douglas in AugustIsle of Man · 205 kmHigh 16.0°C · Low 14.0°C · 78 mm rain
- Glasgow in AugustUnited Kingdom · 215 kmHigh 17.2°C · Low 10.9°C · 101 mm rain
- East Kilbride in AugustUnited Kingdom · 215 kmHigh 16.6°C · Low 10.2°C · 101 mm rain
Read the numbers correctly
Climate, not a promise.
These patterns help compare months. They cannot tell you the weather on a specific day of your trip.
Sources, method and limitsHow these numbers are made (what the highs, lows and rain days mean, the sources and the model cell used for Derry) is explained once on the Derry year overview and on the Sources, method and limits page.