Climate averages 1991–2020

Douglas weather
in September.

A mild, moderately wet month: the 3rd warmest and the 8th driest of the year.

Long-term climate patterns, not a forecast for a particular trip.

Average high 15.1°C Daytime mean, September

Average low 13.1°C Night-time mean, September

Rainfall 85 mm 13 days with ≥1 mm

Daylight 13 h Sunrise to sunset, per day

September is a mild month in Douglas: daytime highs average 15.1°C and nights cool to about 13.1°C. By daytime temperature it is the 3rd warmest of the 12 months.

Expect about 85 mm of rain on roughly 13 days, which makes September a moderately wet month (the 8th driest of the 12 months). Daylight, from sunrise to sunset, lasts about 12 h 46 min on an average September day.

The nearest other city in this atlas is Blackpool (101 km away). In September its highs average 16.0°C, 0.8°C warmer than Douglas, with 110 mm of rain.

From September to October, average highs fall by 2.1°C to 13.1°C, and monthly rainfall rises from 85 mm to 117 mm.

The annual picture

September in context

30-year average

Average highAverage low°C

Monthly rainfall

Average total · mm

Averages from hourly ERA5 reanalysis data. Actual weather varies from year to year. How these numbers are calculated

Every month, side by side

Douglas climate table

1991–2020

Monthly climate averages for Douglas, 1991–2020
Month	Average highHigh / low	Average low	Rainfall mm/month	Rain days ≥1 mm/day	Daylight hours/dayDaylight h/day
January	8.1°C5.8°C	5.8°C	97	16.5	8.08 h
February	7.6°C5.4°C	5.4°C	76	14.3	9.710 h
March	8.1°C5.8°C	5.8°C	70	12.9	11.812 h
April	9.4°C7.1°C	7.1°C	59	11.7	14.014 h
May	11.7°C9.3°C	9.3°C	56	11.2	16.016 h
June	13.8°C11.7°C	11.7°C	64	10.7	17.117 h
July	15.5°C13.5°C	13.5°C	67	12.2	16.617 h
August	16.0°C14.0°C	14.0°C	78	12.9	14.915 h
September, selected	15.1°C13.1°C	13.1°C	85	13.3	12.813 h
October	13.1°C11.0°C	11.0°C	117	16.1	10.611 h
November	10.6°C8.5°C	8.5°C	125	18.5	8.69 h
December	8.9°C6.6°C	6.6°C	114	18.2	7.57 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

Distance from Douglas

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 limits

How these numbers are made (what the highs, lows and rain days mean, the sources and the model cell used for Douglas) is explained once on the Douglas year overview and on the Sources, method and limits page.