New Haven weather in September 2025

The temperatures in New Haven in September are comfortable with low of 16°C and and high up to 24°C.

You can expect about 3 to 8 days of rain in New Haven during the month of September. It’s a good idea to bring along your umbrella so that you don’t get caught in poor weather.

Our weather forecast can give you a great sense of what weather to expect in New Haven in September 2025.

If you’re planning to visit New Haven in the near future, we highly recommend that you review the 14 day weather forecast for New Haven before you arrive.

Temperatures

24° / 16°

Rainy Days

Snowy Days

Dry Days

Rainfall

122

Sun Hours

10.3

Hrs

Sun	Mon	Tue	Wed	Thu	Fri	Sat
	1 25° /15°	2 23° /13°	3 24° /15°	4 26° /16°	5 23° /18°	6 25° /18°
7 25° /17°	8 25° /16°	9 25° /17°	10 26° /17°	11 24° /16°	12 25° /17°	13 25° /18°
14 24° /16°	15 24° /16°	16 22° /15°	17 22° /15°	18 25° /17°	19 25° /18°	20 24° /16°
21 22° /14°	22 21° /15°	23 20° /14°	24 20° /14°	25 20° /13°	26 21° /15°	27 21° /14°
28 20° /14°	29 18° /13°	30 18° /11°

Explore the weather in New Haven in other months

New Haven annual weather

Month	Temperatures	Rainy Days	Dry Days	Snowy Days	Rainfall	Weather	More details
January	2° / -4°	7	15	9	130 mm	Awful	New Haven in January
February	3° / -3°	7	12	10	145 mm	Awful	New Haven in February
March	7° / 0°	8	17	6	153 mm	Awful	New Haven in March
April	13° / 6°	8	21	1	145 mm	Bad	New Haven in April
May	19° / 11°	8	23	0	143 mm	Ok	New Haven in May
June	24° / 16°	8	22	0	154 mm	Good	New Haven in June
July	28° / 20°	8	23	0	179 mm	Good	New Haven in July
August	27° / 20°	7	24	0	170 mm	Good	New Haven in August
September	24° / 16°	6	24	0	122 mm	Perfect	New Haven in September
October	17° / 11°	7	24	0	175 mm	Ok	New Haven in October
November	11° / 5°	7	22	1	121 mm	Bad	New Haven in November
December	5° / 0°	8	17	6	169 mm	Awful	New Haven in December