Climate averages 1991–2020
Harlow weather
in September.
A mild, moderately wet month: the 4th warmest and the 3rd driest of the year.
Long-term climate patterns, not a forecast for a particular trip.
September is a mild month in Harlow: daytime highs average 18.3°C and nights cool to about 11.0°C. By daytime temperature it is the 4th warmest of the 12 months.
Expect about 48 mm of rain on roughly 9 days, which makes September a moderately wet month (the 3rd driest of the 12 months). Daylight, from sunrise to sunset, lasts about 12 h 43 min on an average September day.
The nearest other city in this atlas is Enfield Town (19 km away). In September its highs average 18.4°C, about as warm as Harlow, with 48 mm of rain.
Among the 143 cities listed in the United Kingdom, Harlow ranks joint 17th of 143 for the warmest September highs and joint 18th of 143 for the driest September (rainfall, lowest first). The mean September high of those 143 cities is 17.3°C; Harlow is 1.0°C warmer than that mean.
From September to October, average highs fall by 4.0°C to 14.3°C, and monthly rainfall rises from 48 mm to 56 mm.
The annual picture
September 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
Harlow climate table
| Month | Average highHigh / low | Average low | Rainfall mm/month | Rain days ≥1 mm/day | Daylight hours/dayDaylight h/day |
|---|---|---|---|---|---|
| January | 7.0°C2.0°C | 2.0°C | 51 | 11.0 | 8.48 h |
| February | 7.6°C1.9°C | 1.9°C | 43 | 9.5 | 9.910 h |
| March | 10.0°C3.1°C | 3.1°C | 42 | 10.1 | 11.812 h |
| April | 13.0°C4.8°C | 4.8°C | 50 | 11.4 | 13.814 h |
| May | 16.1°C7.9°C | 7.9°C | 54 | 10.2 | 15.616 h |
| June | 19.0°C11.0°C | 11.0°C | 58 | 10.0 | 16.617 h |
| July | 21.4°C13.2°C | 13.2°C | 58 | 10.8 | 16.216 h |
| August | 21.1°C13.2°C | 13.2°C | 63 | 10.3 | 14.615 h |
| September, selected | 18.3°C11.0°C | 11.0°C | 48 | 9.0 | 12.713 h |
| October | 14.3°C8.2°C | 8.2°C | 56 | 10.4 | 10.711 h |
| November | 10.0°C4.7°C | 4.7°C | 58 | 10.5 | 8.99 h |
| December | 7.3°C2.6°C | 2.6°C | 55 | 11.3 | 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
September in nearby cities
- Enfield Town in SeptemberUnited Kingdom · 19 kmHigh 18.4°C · Low 11.3°C · 48 mm rain
- Walthamstow in SeptemberUnited Kingdom · 23 kmHigh 18.6°C · Low 11.4°C · 45 mm rain
- Ilford in SeptemberUnited Kingdom · 24 kmHigh 18.5°C · Low 11.6°C · 45 mm rain
- Chelmsford in SeptemberUnited Kingdom · 25 kmHigh 18.3°C · Low 11.8°C · 46 mm rain
- Dagenham in SeptemberUnited Kingdom · 25 kmHigh 18.5°C · Low 11.7°C · 45 mm rain
- Stevenage in SeptemberUnited Kingdom · 26 kmHigh 18.1°C · Low 10.8°C · 51 mm rain
- Barking in SeptemberUnited Kingdom · 27 kmHigh 18.6°C · Low 11.5°C · 45 mm rain
- Archway in SeptemberUnited Kingdom · 29 kmHigh 18.2°C · Low 11.1°C · 47 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 Harlow) is explained once on the Harlow year overview and on the Sources, method and limits page.
Enfield Town lies in the same rainfall cell, so its rainfall figures are identical to these; temperatures differ because they come from smaller 0.1° cells.