Climate averages 1991–2020

Newport weather
in September.

A mild, moderately wet month: the 4th warmest and the joint 3rd driest of the year.

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

Average high 17.8°C Daytime mean, September

Average low 10.9°C Night-time mean, September

Rainfall 63 mm 10 days with ≥1 mm

Daylight 13 h Sunrise to sunset, per day

September is a mild month in Newport: daytime highs average 17.8°C and nights cool to about 10.9°C. By daytime temperature it is the 4th warmest of the 12 months.

Expect about 63 mm of rain on roughly 10 days, which makes September a moderately wet month (the joint 3rd driest of the 12 months). Daylight, from sunrise to sunset, lasts about 12 h 42 min on an average September day.

The nearest other city in this atlas is Cardiff (17 km away). In September its highs average 17.2°C, 0.6°C cooler than Newport, with 74 mm of rain.

Among the 143 cities listed in the United Kingdom, Newport ranks joint 54th of 143 for the warmest September highs and joint 103rd of 143 for the driest September (rainfall, lowest first). The mean September high of those 143 cities is 17.3°C; Newport is 0.5°C warmer than that mean.

From September to October, average highs fall by 3.7°C to 14.1°C, and monthly rainfall rises from 63 mm to 88 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

Newport climate table

1991–2020

Monthly climate averages for Newport, 1991–2020
Month	Average highHigh / low	Average low	Rainfall mm/month	Rain days ≥1 mm/day	Daylight hours/dayDaylight h/day
January	7.6°C2.7°C	2.7°C	77	13.4	8.48 h
February	8.1°C2.4°C	2.4°C	61	10.7	9.910 h
March	10.2°C3.4°C	3.4°C	60	10.9	11.812 h
April	12.9°C5.0°C	5.0°C	64	11.1	13.814 h
May	16.0°C8.2°C	8.2°C	68	11.8	15.616 h
June	18.6°C11.1°C	11.1°C	64	10.5	16.617 h
July	20.4°C13.0°C	13.0°C	63	11.1	16.116 h
August	20.1°C13.0°C	13.0°C	74	11.3	14.615 h
September, selected	17.8°C10.9°C	10.9°C	63	10.1	12.713 h
October	14.1°C8.4°C	8.4°C	88	13.1	10.711 h
November	10.5°C5.3°C	5.3°C	84	13.7	8.99 h
December	7.9°C3.1°C	3.1°C	86	13.1	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

Distance from Newport

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 Newport) is explained once on the Newport year overview and on the Sources, method and limits page.