May 18 is generally a great time to visit Ottawa. While there is a slight chance of rain (24%), showers are usually brief. Expect comfortable 19°C weather. Ottawa is seeing high visitor numbers, so iconic spots may be busier than usual.
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Essential Travel Info for Ottawa
Currency
CAD
$ Canadian dollar
Language
English
+1 more
Driving
Right side
Connect
The area codes for Ottawa are613and the ...
Safety
Very High Safety
GPI: 1.389
Ottawa Weather Forecast for May 18
"Mild & Comfortable. Expect average highs of 18.6°C. 24% chance of rain."
What to Wear in Ottawa in May
Based on historical data for May 18, Ottawa typically experiences temperatures between 7.7°C and 18.6°C. We recommend packing light jacket, long pants to stay comfortable. Trends suggest it will stay mostly dry (24% rain probability), but checking the forecast before heading out is always wise.
Complete Packing Guide
Weekly breakdown & essential items for Ottawa
Smart Suitcase
- Light Jacket
- Long Pants
Average High
18.6°C
Daytime Peak
Average Low
7.7°C
Nighttime Low
Feels Like
18.6°C
🌤️ Feels accurate
Rain Chance
24%
Avg 1.7mm if it rains
Cloud Cover
64%
Overcast
Pressure
1014.3 hPa
High volatility
Ottawa Weather Conditions & UV Index
Weather Confidence
30-year variance analysis
Based on 10 years of data
✓ Weather is generally predictable, but pack for minor variations. A light backup layer is recommended.
Sun Exposure
UV Index & Safety Guide
Protection Needed
SPF 30 recommended
04:00 - 10:00
16:00 - 19:00
Type I-II
🔴 18 min to burn
Type III-IV
🟡 27 min to burn
Type V-VI
🟢 45 min to burn
UV estimate based on latitude, season & cloud cover. Actual UV may vary.
Outdoor Comfort
How pleasant is it outside?
Dew Point
12.3°C
Pleasant
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
Busy
65/100 pressure index
Health Advisory
Required
1 vaccine • View Details →
Landing Slots
~115
Daily arrival options (inc. codeshare)
Sunrise, Sunset & Wind in Ottawa
Daylight & Sun
Solar Elevation Cycle
🌅 Sunrise
04:30
☀️ Noon
12:00
🌇 Sunset
19:30
⏱️ Daylight
14h 59m
Wind Speed
15.9 km/h
Gentle breeze
Sunshine
9.7 hrs
Direct Sun (Cloud-free)
Humidity
67%
Slightly humid
Travel Intelligence
Exclusive flight analytics & health data for Ottawa
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 Ottawa
Travel Comfort Index
Real-time tourism conditions
Weather Quality
☀️ Excellent
Tourist Crowds
🟡 Busy
Price Level
💰💰💰 Expensive
Health & Wellbeing
Meteo-Health Forecast
Rapid pressure changes detected. High risk for meteosensitive people.
Weather unlikely to affect joint pain.
Fish are active due to pressure changes.
Air quality is acceptable. Sensitive individuals should limit prolonged outdoor exertion.
Regional Safety Profile
Seismic Activity
Rare minor tremors. Buildings are earthquake-resistant.
"According to 30YearWeather's analysis of 30 years of NASA satellite data, Ottawa on May 18 averages 18.6°C with a 24% precipitation probability. Wedding/Outdoor Event Score: 90/100."
— Source: 30YearWeather.com|Data: NASA POWER (1991-2021)|View Methodology
Ottawa Weather History (2010–2024)
Temperature History
Hall of Fame
Records from last 10 years
Better Alternatives Nearby
Consider these dates within ±7 days
May 25
20.5°C • 26% rain
Score
96
May 23
20.1°C • 26% rain
Score
95
May 24
20.1°C • 27% rain
Score
95
💡 Moving your event by a few days could significantly improve weather conditions
Compare Other Cities
Same date (May 18) in other destinations
🌍 Explore the same date in different destinations around the world
📍 Is Ottawa Worth Visiting on May 18?
Planning a trip to Ottawa on May 18? 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 18.6°C with a 24% historical precipitation risk.
✈️ Travel Logistics: Approximately 115 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 18 recorded in the last 30 years saw temperatures hit 28.9°C in 2017, while the coldest dropped to 0.7°C in 2023.