Norway Oslo Weather in May — Climate Guide
May in Oslo is very-high
Oslo Weather in May — Quick Answer
As of 2026- Avg temp
- 16° / 6°
- Rainfall
- 60mm · 9 days
- Crowds
- Very busy
As of 2026, Oslo in May averages a high of 16°C and low of 6°C with 60mm of rain over about 9 days. Spring ideal — light jacket morning/evening + t-shirt + jeans by day. Midnight sun begins May 15 (sunset around 22:00). May 17 Constitution Day biggest celebration of the year.
May is very-high for Oslo.
May is Oslo's spring sweet-spot month — high 16°C / 61°F, low 6°C / 43°F. Daylight extends from 17 hours to 18 hours by month end. Midnight sun begins May 15 — sun barely sets (sunset around 22:50 in late May, civil twilight all night).
May 17 Constitution Day (Grunnlovsdagen) is Norway's national day and the year's biggest celebration — children's parades wind through every Norwegian city in traditional bunad costumes, the Royal Family appears on the palace balcony waving to crowds on Karl Johans Gate, hot dogs and ice cream consumed in industrial quantities.
Travel score
Oslo May Weather Stats
Avg High
16°C
Avg Low
6°C
Rainy Days
9
60mm total
Sunshine
8h
Daily avg
Humidity
65%
moderate
UV Index
5
Moderate
Wind
9 km/h
Gusts 25
Sea Temp
8°C
freezing
Crowds
Very busy
At attractions
May Sunrise & Sunset
Air Quality
PM2.5
6 μg/m³
PM10
15 μg/m³
Status
good
Feels-Like Temperature & Wind
Feels like
Daytime
16°C
Nighttime
5°C
Humidity and wind affect how the actual temperature feels.
Wind
9 km/h
Max gust 25 km/h
Activities Recommended for May
May Travel Pros & Cons
Pros
- Constitution Day May 17 (most-Norwegian day of the year)
- Midnight sun begins May 15
- Outdoor cafe season starts
- Norway in a Nutshell full operation
- Daylight 17-18 hours
Cons
- Constitution Day hotels surge 50-100%
- Pre-summer crowds rising
- Variable rain still
- Hotel pricing climbing
May Events & Festivals
- Norwegian Constitution Day (May 17, the biggest celebration of the year)
- Bergensbanen + Flåm Railway full season starts
- Midnight sun begins May 15 (Oslo twilight all night)
Oslo in May — Full Picture
May is Oslo's spring sweet-spot month — high 16°C / 61°F, low 6°C / 43°F. Daylight extends from 17 hours to 18 hours by month end. Midnight sun begins May 15 — sun barely sets (sunset around 22:50 in late May, civil twilight all night).
May 17 Constitution Day (Grunnlovsdagen) is Norway's national day and the year's biggest celebration — children's parades wind through every Norwegian city in traditional bunad costumes, the Royal Family appears on the palace balcony waving to crowds on Karl Johans Gate, hot dogs and ice cream consumed in industrial quantities.
The Oslo parade starts at Karl Johans Gate / Oslo S around 10:00 and passes the Royal Palace around noon. Hotels surge 50-100% for the weekend — book 4-6 months ahead if you want to experience this. The most-Norwegian day of the year.
Bergensbanen + Flåm Railway summer season starts — the canonical Norway in a Nutshell day trip from Oslo (Oslo → Myrdal → Flåm → Nærøyfjord cruise → Voss → Oslo) is fully operational.
The smart May move: target the first 2 weeks (pre-May 17, post-Easter) for shoulder pricing or specifically be in Oslo May 17 for Constitution Day. Outdoor cafe season at Aker Brygge + Grünerløkka begins.
What to Wear & What to Pack
Spring ideal — light jacket morning/evening + t-shirt + jeans by day. Midnight sun begins May 15 (sunset around 22:00). May 17 Constitution Day biggest celebration of the year.
Packing Checklist
Seasonal Weather Overview
Spring (Mar·Apr·May)
Current9.3°C
1.3°C
8.7/mo
Summer (Jun·Jul·Aug)
21.7°C
11.7°C
10.7/mo
Autumn (Sep·Oct·Nov)
11°C
4°C
11.3/mo
Winter (Dec·Jan·Feb)
-1°C
-6°C
8.7/mo
Oslo Monthly Weather Comparison
| Month | High | Low | Rain | Sun | Humid | UV | Crowd | Price |
|---|---|---|---|---|---|---|---|---|
| -2° | -7° | 9d·50mm | 1h | 80% | 0 | Quiet | Low season | |
| -1° | -7° | 7d·40mm | 2h | 78% | 1 | Quiet | Low season | |
| 3° | -3° | 8d·50mm | 4h | 75% | 2 | Moderate | Shoulder | |
| 9° | 1° | 9d·50mm | 6h | 70% | 3 | Moderate | Shoulder | |
| May (Best) | 16° | 6° | 9d·60mm | 8h | 65% | 5 | Very busy | Peak |
| June (Best) | 20° | 10° | 10d·70mm | 9h | 65% | 6 | Very busy | Peak |
| July (Best) | 23° | 13° | 11d·80mm | 9h | 65% | 6 | Very busy | Peak |
| August (Best) | 22° | 12° | 11d·90mm | 7h | 70% | 5 | Very busy | Peak |
| 17° | 8° | 11d·90mm | 5h | 75% | 3 | Busy | Shoulder | |
| 11° | 4° | 12d·100mm | 3h | 80% | 2 | Moderate | Shoulder | |
| 5° | 0° | 11d·80mm | 1h | 80% | 1 | Quiet | Low season | |
| 0° | -4° | 10d·60mm | 1h | 82% | 0 | Busy | Peak |
View Other Months
Oslo May Hotel Picks
Frequently Asked Questions
Is May a good time to visit Oslo?
Oslo in May is very-high. Tourist crowds are very busy and flight/hotel prices are peak.
What's the average temperature in Oslo in May?
Oslo May averages a high of 16°C and a low of 6°C.
Does it rain much in Oslo in May?
Oslo May averages 60mm of rainfall over about 9 rainy days.
What should I wear in Oslo in May?
Spring ideal — light jacket morning/evening + t-shirt + jeans by day. Midnight sun begins May 15 (sunset around 22:00). May 17 Constitution Day biggest celebration of the year.
What time are sunrise and sunset in Oslo in May?
Oslo May sunrise is 05:00 and sunset is 21:30, with 16h 30m of daylight.
What's the air quality like in Oslo in May?
Oslo May air quality (AQI) averages 24, rated Good. PM2.5 averages 6μg/m³.
What activities are recommended in Oslo in May?
In May, Oslo is great for May 17 Constitution Day parade Karl Johans Gate, Vigeland Park spring bloom walk, Bygdøy ferry to peninsula museums.
Is May peak season in Oslo?
Oslo May crowds are very busy and prices are peak. Advance reservations are strongly recommended.
Best Months to Visit Oslo
View Other Months
Planning a May trip to Oslo?
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Why you can trust weather guide
Based in Chiang Mai for 8+ years, with 30+ countries visited across Southeast Asia, Japan, and Europe. Every detail in this guide is primary-source verified as of April 2026, with prices auto-refreshed via live exchange rate APIs. This isn't AI-generated boilerplate — it's written from the perspective of someone who has actually been there.