Lewiston in September

7.7out of 10

Yes, a good time to go

Mild: highs around 21°C. Frequent rain: about 9 rainy days.

21°CAvg high
12°CAvg low
9Rainy days (87 mm)
12:17 hDaylight
06:27Sunrise · 18:44 Sunset

Why this score

  • Mild: highs around 21°C
  • Frequent rain: about 9 rainy days

What to wear and pack

  • Layers you can add or remove
  • 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 (2.7 days). Averages cover 30 years (1991–2020). Individual days can differ a lot.

Year at a glance

-1° -10° J 0° -9° F 5° -4° M 11° 2° A 17° 8° M 22° 13° J 26° 17° J 25° 16° A 21° 12° S 14° 6° O 8° 1° N 2° -5° D Rainy days

Weather by month

MonthAvg highAvg lowRainfall Rainy daysHumiditySunshine Score
January -1°C-10°C80 mm 9– – 3.9
February 0°C-9°C77 mm 9– – 3.9
March 5°C-4°C97 mm 10– – 4.5
April 11°C2°C98 mm 10– – 5.8
May 17°C8°C79 mm 11– – 6.9
June 22°C13°C94 mm 11– – 7.6
July 26°C17°C79 mm 10– – 7.8
August 25°C16°C80 mm 9– – 7.9
September 21°C12°C87 mm 9– – 7.7
October 14°C6°C113 mm 10– – 6.4
November 8°C1°C90 mm 9– – 5.4
December 2°C-5°C104 mm 10– – 3.9

Frequently asked questions

How hot is Lewiston in September?

Daytime highs average 21°C and nights about 12°C.

When is the best time to visit Lewiston?

The best months are August, July, September, June.