Climate averages 1991–2020
Harrow weather
in August.
A mild, moderately wet month: the 2nd warmest and the 11th driest of the year.
Long-term climate patterns, not a forecast for a particular trip.
August is a mild month in Harrow: daytime highs average 20.8°C and nights cool to about 13.3°C. By daytime temperature it is the 2nd warmest of the 12 months.
Expect about 61 mm of rain on roughly 10 days, which makes August a moderately wet month (the 11th driest of the 12 months). Daylight, from sunrise to sunset, lasts about 14 h 37 min on an average August day.
The nearest other city in this atlas is Hayes (9 km away). In August its highs average 20.9°C, about as warm as Harrow, with 60 mm of rain.
Among the 143 cities listed in the United Kingdom, Harrow ranks joint 28th of 143 for the warmest August highs and joint 16th of 143 for the driest August (rainfall, lowest first). The mean August high of those 143 cities is 19.7°C; Harrow is 1.1°C warmer than that mean.
From August to September, average highs fall by 2.7°C to 18.1°C, and monthly rainfall falls from 61 mm to 47 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
Harrow climate table
| Month | Average highHigh / low | Average low | Rainfall mm/month | Rain days ≥1 mm/day | Daylight hours/dayDaylight h/day |
|---|---|---|---|---|---|
| January | 7.1°C2.3°C | 2.3°C | 55 | 10.9 | 8.48 h |
| February | 7.6°C2.2°C | 2.2°C | 45 | 9.4 | 9.910 h |
| March | 10.0°C3.4°C | 3.4°C | 42 | 10.2 | 11.812 h |
| April | 13.0°C5.1°C | 5.1°C | 49 | 10.9 | 13.814 h |
| May | 16.1°C8.2°C | 8.2°C | 52 | 9.8 | 15.616 h |
| June | 19.0°C11.2°C | 11.2°C | 56 | 10.0 | 16.617 h |
| July | 21.2°C13.4°C | 13.4°C | 54 | 10.6 | 16.116 h |
| August, selected | 20.8°C13.3°C | 13.3°C | 61 | 10.2 | 14.615 h |
| September | 18.1°C11.1°C | 11.1°C | 47 | 9.0 | 12.713 h |
| October | 14.2°C8.4°C | 8.4°C | 58 | 11.2 | 10.711 h |
| November | 10.0°C5.1°C | 5.1°C | 63 | 11.0 | 8.99 h |
| December | 7.4°C2.9°C | 2.9°C | 58 | 11.2 | 7.98 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
- Hayes in AugustUnited Kingdom · 9 kmHigh 20.9°C · Low 13.4°C · 60 mm rain
- Watford in AugustUnited Kingdom · 10 kmHigh 20.8°C · Low 13.3°C · 62 mm rain
- Uxbridge in AugustUnited Kingdom · 11 kmHigh 20.8°C · Low 13.3°C · 60 mm rain
- Archway in AugustUnited Kingdom · 14 kmHigh 21.0°C · Low 13.4°C · 61 mm rain
- Fulham in AugustUnited Kingdom · 14 kmHigh 21.3°C · Low 13.5°C · 61 mm rain
- London in AugustUnited Kingdom · 16 kmHigh 21.3°C · Low 13.4°C · 61 mm rain
- Enfield Town in AugustUnited Kingdom · 19 kmHigh 21.2°C · Low 13.5°C · 63 mm rain
- St Albans in AugustUnited Kingdom · 19 kmHigh 20.7°C · Low 13.1°C · 62 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 Harrow) is explained once on the Harrow year overview and on the Sources, method and limits page.
London, Archway and Fulham lie in the same rainfall cell, so their rainfall figures are identical to these; temperatures differ because they come from smaller 0.1° cells.