Avg High
Calgary in May
Avg Low
Rain
Daylight
16h
What to expect
Calgary is in late spring during May, a shoulder-season stretch where conditions can nudge warmer or cooler week to week. It usually feels cool and fresh, and bigger day–night swings than you might expect. Daylight stays generous for longer outdoor plans. Conditions tend to feel steady, which makes planning simple.
May in context
How it compares to the rest of the year in Calgary.
Hottest (avg)
#5 / 12
Wettest (avg)
#2 / 12
Daylight Hours
#3 / 12
Windiest (avg)
#5 / 12
Highest UV
#3 / 12
Most Humid
#11 / 12
Monthly climate breakdown
Temperature
- Daytime high
-
- Nighttime low
-
- Feels like (avg)
-
Sunshine
- Daylight hours
- 15.6 h
- UV index (max)
- 7
- Typical sun hours
- 04:44 - 20:20
Rain & Snow
- Total rain
-
- Rainy days
- 14 days
- Cloud cover (avg)
- 62%
- Snowfall
-
Humidity & Wind
- Humidity (avg)
- 60%
- Wind (avg)
-
- Wind (max gusts)
-
Daily climate explorer
Day 15 selected for May. Typical high 16.9°C and low 3.9°C.
Typical disruptions in May
Based on 30 years of historical data, these are the disruption patterns most likely to affect plans in May.
Cold High impact
Cold feels-like nights Measures: Cold feels-like nights (min <=5C). Observed about 91% of days (28.3 days/month) in May. Historical risk signal only, not a day-by-day forecast.
28.3 days / month
~91% of days
Why this matters
- Expected days 28.3 days / month
- Probability ~91% of days
- Intensity Up to ~4°C (P95)
Cold feels-like nights are possible on ~28 days. Long outdoor blocks become harder to sustain, so layer up and keep a warm indoor fallback nearby.
Cold High impact
Freezing nights Measures: Freezing nights (min <=0C). Observed about 21% of days (6.5 days/month) in May. Historical risk signal only, not a day-by-day forecast.
6.5 days / month
~21% of days
Why this matters
- Expected days 6.5 days / month
- Probability ~21% of days
- Intensity Up to ~-0°C (P95)
Freezing nights are possible on ~6 days. Fixed-time outdoor plans are safer with a backup option and flexible timing.
Rain High impact
Washout risk Measures: Washout day risk. Observed about 15% of days (4.6 days/month) in May. Historical risk signal only, not a day-by-day forecast.
4.6 days / month
~15% of days
Why this matters
- Expected days 4.6 days / month
- Probability ~15% of days
- Intensity Up to ~25mm (P95)
Washout conditions are possible on ~5 days. Outdoor plans can become unreliable, so keep an indoor backup and flexibility around start times.
Wind High impact
Strong gusts Measures: Strong gust days (>=60 km/h). Observed about 3% of days (0.8 days/month) in May. Historical risk signal only, not a day-by-day forecast.
0.8 days / month
~3% of days
Why this matters
- Expected days 0.8 days / month
- Probability ~3% of days
- Intensity Up to ~79km/h (P95)
Strong gusts are possible on ~1 days. Exposed activities and transport links are more likely to be disrupted, so keep sheltered alternatives ready.
Rain Moderate
Rain disruption Measures: Likely rain disruption days. Observed about 15% of days (4.7 days/month) in May. Historical risk signal only, not a day-by-day forecast.
4.7 days / month
~15% of days
Why this matters
- Expected days 4.7 days / month
- Probability ~15% of days
- Intensity Up to ~25mm (P95)
Rain disruption risk appears on ~5 days. Outdoor plans can become unreliable, so keep an indoor backup and flexibility around start times.
Snow Moderate
Snow days Measures: Snow days (>=0.1mm snowfall). Observed about 11% of days (3.5 days/month) in May. Historical risk signal only, not a day-by-day forecast.
3.5 days / month
~11% of days
Why this matters
- Expected days 3.5 days / month
- Probability ~11% of days
- Intensity Up to ~8.4mm (P95)
Snowfall is possible on ~3 days. Fixed-time outdoor plans are safer with a backup option and flexible timing.
Show all disruptions (21 more)
Rain High impact
Washout run Measures: Multi-day washout runs. Observed about 0.9 days/month in May. Historical risk signal only, not a day-by-day forecast.
0.9 days / month
Probability unavailable
Why this matters
- Expected days 0.9 days / month
- Probability —
- Intensity Up to ~30mm (P95)
Multi-day washout runs are possible on ~1 days. Outdoor plans can become unreliable, so keep an indoor backup and flexibility around start times.
Wind High impact
Stormy conditions Measures: Storm-impact proxy days. Observed about 1% of days (0.4 days/month) in May. Historical risk signal only, not a day-by-day forecast.
0.4 days / month
~1% of days
Why this matters
- Expected days 0.4 days / month
- Probability ~1% of days
- Intensity Up to ~74km/h (P95)
Stormy conditions are possible on ~0 days. Exposed activities and transport links are more likely to be disrupted, so keep sheltered alternatives ready.
Rain High impact
Very heavy rain Measures: Very heavy rain days (>=25mm). Observed about 1% of days (0.3 days/month) in May. Historical risk signal only, not a day-by-day forecast.
0.3 days / month
~1% of days
Why this matters
- Expected days 0.3 days / month
- Probability ~1% of days
- Intensity Up to ~39mm (P95)
Very heavy rain is possible on ~0 days. Outdoor plans can become unreliable, so keep an indoor backup and flexibility around start times.
Cold Moderate
Hard freeze nights Measures: Hard freeze nights (min <=-2C). Observed about 9% of days (2.7 days/month) in May. Historical risk signal only, not a day-by-day forecast.
2.7 days / month
~9% of days
Why this matters
- Expected days 2.7 days / month
- Probability ~9% of days
- Intensity Up to ~-2°C (P95)
Hard freeze conditions are possible on ~3 days. Long outdoor blocks become harder to sustain, so layer up and keep a warm indoor fallback nearby.
Rain Moderate
Heavy rain days Measures: Heavy rain days (>=10mm). Observed about 5% of days (1.6 days/month) in May. Historical risk signal only, not a day-by-day forecast.
1.6 days / month
~5% of days
Why this matters
- Expected days 1.6 days / month
- Probability ~5% of days
- Intensity Up to ~29mm (P95)
Heavy rain is possible on ~2 days. Outdoor plans can become unreliable, so keep an indoor backup and flexibility around start times.
Visibility Moderate
Fog-likely signal Measures: Fog-likely visibility proxy. Observed about 4% of days (1.3 days/month) in May. Historical risk signal only, not a day-by-day forecast.
1.3 days / month
~4% of days
Why this matters
- Expected days 1.3 days / month
- Probability ~4% of days
- Intensity Up to ~98% (P95)
Fog-likely conditions are possible on ~1 days. Fixed-time outdoor plans are safer with a backup option and flexible timing.
Cold Minor
Cold nights Measures: Cold nights (min <=5C). Observed about 70% of days (21.5 days/month) in May. Historical risk signal only, not a day-by-day forecast.
21.5 days / month
~70% of days
Why this matters
- Expected days 21.5 days / month
- Probability ~70% of days
- Intensity Up to ~5°C (P95)
Cold nights are possible on ~22 days. Long outdoor blocks become harder to sustain, so layer up and keep a warm indoor fallback nearby.
Rain Minor
Wet days Measures: Wet days (>=0.1mm). Observed about 58% of days (18.1 days/month) in May. Historical risk signal only, not a day-by-day forecast.
18.1 days / month
~58% of days
Why this matters
- Expected days 18.1 days / month
- Probability ~58% of days
- Intensity Up to ~16mm (P95)
Measurable rain is possible on ~18 days. Fixed-time outdoor plans are safer with a backup option and flexible timing.
Cloud Minor
Cloudy days Measures: Cloudy days (cloud cover >=60%). Observed about 57% of days (17.6 days/month) in May. Historical risk signal only, not a day-by-day forecast.
17.6 days / month
~57% of days
Why this matters
- Expected days 17.6 days / month
- Probability ~57% of days
- Intensity Up to ~100% (P95)
Cloudy skies are possible on ~18 days. Fixed-time outdoor plans are safer with a backup option and flexible timing.
Rain Minor
Rainy hours Measures: Rain-hours signal (>=3h rain). Observed about 40% of days (12.5 days/month) in May. Historical risk signal only, not a day-by-day forecast.
12.5 days / month
~40% of days
Why this matters
- Expected days 12.5 days / month
- Probability ~40% of days
- Intensity Up to ~23h (P95)
Several rainy hours are possible on ~13 days. Outdoor plans can become unreliable, so keep an indoor backup and flexibility around start times.
Cloud Minor
Mostly cloudy days Measures: Mostly cloudy days (cloud cover >=80%). Observed about 34% of days (10.6 days/month) in May. Historical risk signal only, not a day-by-day forecast.
10.6 days / month
~34% of days
Why this matters
- Expected days 10.6 days / month
- Probability ~34% of days
- Intensity Up to ~100% (P95)
Mostly cloudy skies are possible on ~11 days. Fixed-time outdoor plans are safer with a backup option and flexible timing.
Wind Minor
Gusty days Measures: Gusty days (>=40 km/h). Observed about 33% of days (10.1 days/month) in May. Historical risk signal only, not a day-by-day forecast.
10.1 days / month
~33% of days
Why this matters
- Expected days 10.1 days / month
- Probability ~33% of days
- Intensity Up to ~62km/h (P95)
Gusty conditions are possible on ~10 days. Exposed activities and transport links are more likely to be disrupted, so keep sheltered alternatives ready.
Rain Minor
Wet most of day Measures: Wet-most-of-day signal (>=6h rain). Observed about 28% of days (8.7 days/month) in May. Historical risk signal only, not a day-by-day forecast.
8.7 days / month
~28% of days
Why this matters
- Expected days 8.7 days / month
- Probability ~28% of days
- Intensity Up to ~24h (P95)
Wet-most-of-day conditions are possible on ~9 days. Outdoor plans can become unreliable, so keep an indoor backup and flexibility around start times.
Cold Minor
Cold days Measures: Cold days (max <=10C). Observed about 16% of days (5.0 days/month) in May. Historical risk signal only, not a day-by-day forecast.
5.0 days / month
~16% of days
Why this matters
- Expected days 5.0 days / month
- Probability ~16% of days
- Intensity Up to ~10°C (P95)
Cold daytime conditions are possible on ~5 days. Long outdoor blocks become harder to sustain, so layer up and keep a warm indoor fallback nearby.
Cloud Minor
Overcast days Measures: Overcast days (cloud cover >=95%). Observed about 15% of days (4.7 days/month) in May. Historical risk signal only, not a day-by-day forecast.
4.7 days / month
~15% of days
Why this matters
- Expected days 4.7 days / month
- Probability ~15% of days
- Intensity Up to ~100% (P95)
Overcast skies are possible on ~5 days. Fixed-time outdoor plans are safer with a backup option and flexible timing.
Humidity Minor
High humidity Measures: High humidity days (RH >=80%). Observed about 12% of days (3.9 days/month) in May. Historical risk signal only, not a day-by-day forecast.
3.9 days / month
~12% of days
Why this matters
- Expected days 3.9 days / month
- Probability ~12% of days
- Intensity Up to ~97% (P95)
High humidity is possible on ~4 days. Comfort and pace can drop quickly, so plan shorter outdoor blocks with air-conditioned backup stops.
Other Minor
Low visibility proxy: same as fog-likely (RH ≥90% AND cloud ≥95%) — true visibility requires hourly visibility data Measures: Low visibility proxy: same as fog-likely (RH ≥90% AND cloud ≥95%) — true visibility requires hourly visibility data. Observed about 4% of days (1.3 days/month) in May. Historical risk signal only, not a day-by-day forecast.
1.3 days / month
~4% of days
Why this matters
- Expected days 1.3 days / month
- Probability ~4% of days
- Intensity Up to ~98 (P95)
Low visibility proxy: same as fog-likely (RH ≥90% AND cloud ≥95%) — true visibility requires hourly visibility data is possible on ~1 days. Fixed-time outdoor plans are safer with a backup option and flexible timing.
Cold Minor
Cold snap run Measures: Cold snap runs (>=3 cold days). Observed about 0.6 days/month in May. Historical risk signal only, not a day-by-day forecast.
0.6 days / month
Probability unavailable
Why this matters
- Expected days 0.6 days / month
- Probability —
- Intensity Up to ~10°C (P95)
Cold snap runs are possible on ~1 days. Long outdoor blocks become harder to sustain, so layer up and keep a warm indoor fallback nearby.
Other Minor
Heavy snowfall (INACTIVE until snowfall_sum units confirmed; set threshold once units are verified) Measures: Heavy snowfall (INACTIVE until snowfall_sum units confirmed; set threshold once units are verified). Observed about 1% of days (0.3 days/month) in May. Historical risk signal only, not a day-by-day forecast.
0.3 days / month
~1% of days
Why this matters
- Expected days 0.3 days / month
- Probability ~1% of days
- Intensity Up to ~15 (P95)
Heavy snowfall (INACTIVE until snowfall_sum units confirmed; set threshold once units are verified) is possible on ~0 days. Fixed-time outdoor plans are safer with a backup option and flexible timing.
Wind Minor
Breezy days Measures: Breezy days (mean wind >=25 km/h). Observed about 1% of days (0.2 days/month) in May. Historical risk signal only, not a day-by-day forecast.
0.2 days / month
~1% of days
Why this matters
- Expected days 0.2 days / month
- Probability ~1% of days
- Intensity Up to ~30km/h (P95)
Breezy conditions are possible on ~0 days. Exposed activities and transport links are more likely to be disrupted, so keep sheltered alternatives ready.
Cold Minor
Wind chill risk Measures: Wind chill risk days. Observed about 1% of days (0.2 days/month) in May. Historical risk signal only, not a day-by-day forecast.
0.2 days / month
~1% of days
Why this matters
- Expected days 0.2 days / month
- Probability ~1% of days
- Intensity Up to ~-3°C (P95)
Wind chill risk is possible on ~0 days. Exposed activities and transport links are more likely to be disrupted, so keep sheltered alternatives ready.
Frequently asked questions
Is May a good time to visit Calgary?
Typical May days in Calgary reach highs of 16°C (61°F) with nights around 3°C (37°F). It usually feels cool by day and cold after dark. It is among the wetter months, so it is wise to have some indoor backup plans or flexible activities.
What are temperatures like in May?
Daytime temperatures in May typically peak near 16°C (61°F), while nights drop to around 3°C (37°F). Expect cool afternoons and cold evenings.
How much does it rain in May?
Rainfall in May averages 70 mm (2.8 in) across roughly 14 days. Overall it is a very wet time of year, so a light rain jacket and waterproof shoes are very handy.
How many hours of daylight are there in May?
You can expect about 16 hours of daylight in May. Sunrise is typically around 04:44 and sunset near 20:20. Very long days give you plenty of daylight for exploring.
How strong is the sun in May?
UV levels are often high (around 7). Regular sunscreen and a hat are recommended.
Is it windy in May?
In May, average wind speeds are around 11 km/h (7 mph), with gusts on the windiest days reaching about 50 km/h (31 mph). On the ground, it is it often feels breezy, especially in more exposed spots or along the coast.