Thermograph

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

Weather in South Boston, Massachusetts, United States in September

In an average September, South Boston sees a daily high around 74°F and a low around 54°F, based on 1981–2026 of local climate records.

Average high74°F
Typical high range65°F to 83°F
Average low54°F
Typical low range46°F to 63°F
Average daily precipitation0.10 in

September records

The most extreme September on record for each metric, across 1981–2026. For rainfall, the wettest and driest are by total September accumulation.

High

Highest 97°F 2002-09-09
Lowest 53°F 1992-09-30

Low

Highest 71°F 2010-09-03
Lowest 35°F 1991-09-30

Feels-like

Highest 119°F 2018-09-06
Lowest 29°F 1991-09-30

Humidity

Highest 20.5 g/m³ 2023-09-08
Lowest 4.1 g/m³ 1981-09-30

Wind

Highest 16 mph 1985-09-27
Lowest 3 mph 1999-09-15

Precip

Wettest 8.74 in 1999
Driest 1.34 in 2014

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