Thermograph

How unusual is the weather? Graded against ~45 years of local climate history.

Weather in Portsmouth in September

In an average September, Portsmouth sees a daily high around 18°C and a low around 14°C, based on 1980–2026 of local climate records.

Average high18°C
Typical high range16°C to 20°C
Average low14°C
Typical low range11°C to 16°C
Average daily precipitation3 mm

September records

The most extreme September on record for each metric, across 1980–2026. For rainfall, the wettest and driest are by total September accumulation.

High

Highest 25°C 2023-09-09
Lowest 11°C 1993-09-27

Low

Highest 19°C 2023-09-07
Lowest 8°C 2010-09-25

Feels-like

Highest 25°C 2023-09-09
Lowest 3°C 2010-09-25

Humidity

Highest 15.5 g/m³ 2023-09-07
Lowest 6.2 g/m³ 2007-09-18

Wind

Highest 61 km/h 1981-09-19
Lowest 7 km/h 2023-09-08

Gust

Highest 102 km/h 1981-09-19
Lowest 11 km/h 2023-09-08

Precip

Wettest 165 mm 2024
Driest 11 mm 2014

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