Siena in September

7.8out of 10

Yes, a good time to go

Warm and comfortable: highs around 24°C. Frequent rain: about 9 rainy days.

24°CAvg high
14°CAvg low
9Rainy days (92 mm)
12:17 hDaylight
07:01Sunrise · 19:17 Sunset

Why this score

  • Warm and comfortable: highs around 24°C
  • Frequent rain: about 9 rainy days

What to wear and pack

  • T-shirts and light layers
  • A light jacket for cooler evenings
  • Rain jacket or compact umbrella

How reliable is the forecast?

Rainfall in September is fairly consistent from year to year (2.8 days). Averages cover 30 years (1991–2020). Individual days can differ a lot.

Year at a glance

9° 2° J 10° 2° F 14° 4° M 17° 7° A 22° 11° M 26° 15° J 29° 17° J 30° 18° A 24° 14° S 19° 10° O 14° 6° N 10° 2° D Rainy days

Weather by month

MonthAvg highAvg lowRainfall Rainy daysHumiditySunshine Score
January 9°C2°C55 mm 8– – 5.8
February 10°C2°C65 mm 8– – 6.0
March 14°C4°C66 mm 9– – 6.6
April 17°C7°C79 mm 11– – 6.8
May 22°C11°C71 mm 10– – 7.7
June 26°C15°C50 mm 8– – 8.1
July 29°C17°C31 mm 5– – 8.4
August 30°C18°C40 mm 6– – 8.1
September 24°C14°C92 mm 9– – 7.8
October 19°C10°C109 mm 10– – 7.1
November 14°C6°C119 mm 12– – 6.0
December 10°C2°C79 mm 10– – 5.8

Frequently asked questions

How hot is Siena in September?

Daytime highs average 24°C and nights about 14°C.

When is the best time to visit Siena?

The best months are July, June, August.