Sioux Falls in May

7.1out of 10

Possible, with caveats

Mild: highs around 21°C. Frequent rain: about 13 rainy days.

21°CAvg high
10°CAvg low
13Rainy days (114 mm)
14:31 hDaylight
06:08Sunrise · 20:39 Sunset

Why this score

  • Mild: highs around 21°C
  • Frequent rain: about 13 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?

Rain in May varies a lot between years (±3.7 rainy days), so check the forecast closer to your trip. Averages cover 30 years (1991–2020). Individual days can differ a lot.

Year at a glance

-3° -12° J 0° -10° F 7° -4° M 15° 3° A 21° 10° M 27° 16° J 29° 18° J 27° 16° A 24° 12° S 16° 4° O 7° -3° N -1° -9° D Rainy days

Weather by month

MonthAvg highAvg lowRainfall Rainy daysHumiditySunshine Score
January -3°C-12°C20 mm 5– – 4.5
February 0°C-10°C24 mm 5– – 4.4
March 7°C-4°C47 mm 7– – 5.5
April 15°C3°C90 mm 10– – 6.5
May 21°C10°C114 mm 13– – 7.1
June 27°C16°C131 mm 12– – 7.2
July 29°C18°C84 mm 9– – 7.9
August 27°C16°C84 mm 9– – 7.9
September 24°C12°C81 mm 8– – 8.0
October 16°C4°C61 mm 7– – 7.1
November 7°C-3°C40 mm 6– – 5.5
December -1°C-9°C27 mm 5– – 4.4

Frequently asked questions

How hot is Sioux Falls in May?

Daytime highs average 21°C and nights about 10°C.

When is the best time to visit Sioux Falls?

The best months are September, July, August.