May 21 is generally a great time to visit Calgary. While there is a slight chance of rain (27%), showers are usually brief. Expect comfortable 16°C weather. Calgary is currently in its most popular travel window, meaning vibrant crowds and premium pricing.
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Essential Travel Info for Calgary
Currency
CAD
$ Canadian dollar
Language
English
+1 more
Driving
Right side
Connect
The area codes in Calgary are403and587, ...
Safety
Very High Safety
GPI: 1.389
Calgary Weather Forecast for May 21
"Mild & Comfortable. Expect average highs of 15.8°C. 27% chance of snow."
What to Wear in Calgary in May
Based on historical data for May 21, Calgary typically experiences temperatures between 3.8°C and 15.8°C. We recommend packing heavy coat, scarf, gloves along with other layers to stay comfortable. With a 27% chance of rain, keeping a raincoat or umbrella handy is a smart move.
Complete Packing Guide
Weekly breakdown & essential items for Calgary
Smart Suitcase
- Heavy Coat
- Scarf
- Gloves
- Layers (Onion System)
Average High
15.8°C
Daytime Peak
Average Low
3.8°C
Nighttime Low
Feels Like
15.8°C
🌤️ Feels accurate
Snow Chance
27%
Avg 1.9mm if it snows
Snowfall
0.3 cm
~27% chance
Pressure
1012.9 hPa
Medium volatility
Calgary Weather Conditions & UV Index
Weather Confidence
30-year variance analysis
Based on 10 years of data
❓ Expect variable conditions. Have flexible plans and pack for multiple weather scenarios.
Sun Exposure
UV Index & Safety Guide
Protection Needed
SPF 30 recommended
04:00 - 10:00
16:00 - 20:00
Type I-II
🔴 19 min to burn
Type III-IV
🟡 29 min to burn
Type V-VI
🟢 48 min to burn
UV estimate based on latitude, season & cloud cover. Actual UV may vary.
Outdoor Comfort
How pleasant is it outside?
Dew Point
8.5°C
Dry air
Heat Stress
Low
No heat warning
😊 Best outdoor time:
Any time during daylight hours
Travel & Logistics Insights
Local Calendar
Business Day
Standard hours in Canada
Flight Traffic
High
100/100 pressure index
Health Advisory
Required
1 vaccine • View Details →
Landing Slots
~296
Daily arrival options (inc. codeshare)
Sunrise, Sunset & Wind in Calgary
Daylight & Sun
Solar Elevation Cycle
🌅 Sunrise
04:39
☀️ Noon
12:34
🌇 Sunset
20:29
⏱️ Daylight
15h 49m
Wind Speed
16.2 km/h
Gentle breeze
Sunshine
10.9 hrs
Direct Sun (Cloud-free)
Humidity
62%
Slightly humid
Travel Intelligence
Exclusive flight analytics & health data for Calgary
Smart Flight Estimator
Airport-to-Airport Logistics
unlock smart flight estimates
Add your home location in settings to see airport details.
Travel Health & Safety in Calgary
Travel Comfort Index
Real-time tourism conditions
Weather Quality
⛅ Good
Tourist Crowds
🟡 Busy
Price Level
💰💰💰 Expensive
Health & Wellbeing
Meteo-Health Forecast
Moderate fluctuations. Some sensitivity possible.
Weather unlikely to affect joint pain.
Moderate fish activity expected.
Air quality is acceptable. Sensitive individuals should limit prolonged outdoor exertion.
Regional Safety Profile
Seismic Activity
Zero seismic activity detected in 30 years.
"According to 30YearWeather's analysis of 30 years of NASA satellite data, Calgary on May 21 averages 15.8°C with a 27% precipitation probability. Wedding/Outdoor Event Score: 77/100."
— Source: 30YearWeather.com|Data: NASA POWER (1991-2021)|View Methodology
Calgary Weather History (2010–2024)
Temperature History
Hall of Fame
Records from last 10 years
Better Alternatives Nearby
Consider these dates within ±7 days
May 28
19.1°C • 17% rain
Score
91
May 27
18.5°C • 22% rain
Score
88
May 26
17.8°C • 25% rain
Score
85
💡 Moving your event by a few days could significantly improve weather conditions
Compare Other Cities
Same date (May 21) in other destinations
🌍 Explore the same date in different destinations around the world
📍 Is Calgary Worth Visiting on May 21?
Planning a trip to Calgary on May 21? Our historical weather analysis based on 30 years of NASA satellite data shows that this time of year is characterized by pleasant mild weather averaging 15.8°C with a 27% historical precipitation risk.
✈️ Travel Logistics: Approximately 296 landing slots available daily during this period, indicating manageable crowd levels.
💉 Health Advisory: 6 vaccinations are recommended for Canada, including COVID-19.
📊 Historical Extremes: The hottest May 21 recorded in the last 30 years saw temperatures hit 29.1°C in 2023, while the coldest dropped to -1.3°C in 2021.