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Ottawa vs Castries
Comparing Ottawa change · Castries change
Castries is the warmer of the two — about 20°C on the annual average; Castries is the wetter, with 1031 mm more rain a year, and Castries the sunnier.
How the seasons compare
The differences between Ottawa and Castries, in everyday terms.
Summers
Castries has hotter summers
Ottawa: Warm
Castries: Warm
Winters
Castries has far milder winters
Ottawa: Very cold
Castries: Stays warm
Rain & snow
Castries is wetter
Ottawa: Moderate rainfall
Castries: Very wet
Sky
Castries is sunnier
Ottawa: Often cloudy
Castries: Fairly sunny
Month-by-month charts
Temperature
Castries is the warmer of the two — about 20°C on the annual average.
Precipitation
Castries is the wetter — about 1031 mm more across the year.
Clear skies
Castries has the clearer skies — the higher line.
Exact monthly numbers
Tap a metric to open its full table. Desktop shows all twelve months; on a phone each metric splits into Jan–Jun and Jul–Dec.
Avg high (°C) Castries runs higher most of the year
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Ottawa | -5 | -3 | 3 | 11 | 20 | 24 | 27 | 26 | 21 | 13 | 6 | -2 |
| Castries | 27 | 27 | 27 | 28 | 28 | 28 | 28 | 29 | 29 | 29 | 28 | 27 |
| Difference | +32 | +30 | +24 | +16 | +9 | +4 | +2 | +3 | +8 | +15 | +22 | +29 |
| Jan – Jun | Jan | Feb | Mar | Apr | May | Jun |
|---|---|---|---|---|---|---|
| Ottawa | -5 | -3 | 3 | 11 | 20 | 24 |
| Castries | 27 | 27 | 27 | 28 | 28 | 28 |
| Difference | +32 | +30 | +24 | +16 | +9 | +4 |
| Jul – Dec | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|
| Ottawa | 27 | 26 | 21 | 13 | 6 | -2 |
| Castries | 28 | 29 | 29 | 29 | 28 | 27 |
| Difference | +2 | +3 | +8 | +15 | +22 | +29 |
Avg low (°C) Castries runs higher most of the year
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Ottawa | -14 | -13 | -7 | 1 | 8 | 14 | 16 | 15 | 11 | 4 | -2 | -8 |
| Castries | 26 | 25 | 25 | 26 | 27 | 27 | 27 | 28 | 28 | 28 | 27 | 26 |
| Difference | +39 | +38 | +32 | +25 | +18 | +14 | +11 | +13 | +17 | +23 | +29 | +35 |
| Jan – Jun | Jan | Feb | Mar | Apr | May | Jun |
|---|---|---|---|---|---|---|
| Ottawa | -14 | -13 | -7 | 1 | 8 | 14 |
| Castries | 26 | 25 | 25 | 26 | 27 | 27 |
| Difference | +39 | +38 | +32 | +25 | +18 | +14 |
| Jul – Dec | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|
| Ottawa | 16 | 15 | 11 | 4 | -2 | -8 |
| Castries | 27 | 28 | 28 | 28 | 27 | 26 |
| Difference | +11 | +13 | +17 | +23 | +29 | +35 |
Precipitation (mm) Castries runs higher most of the year
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Ottawa | 65 | 52 | 62 | 80 | 80 | 95 | 92 | 87 | 87 | 89 | 70 | 72 |
| Castries | 113 | 76 | 66 | 90 | 114 | 134 | 216 | 291 | 224 | 246 | 243 | 149 |
| Difference | +48 | +24 | +5 | +10 | +34 | +38 | +124 | +205 | +137 | +157 | +172 | +77 |
| Jan – Jun | Jan | Feb | Mar | Apr | May | Jun |
|---|---|---|---|---|---|---|
| Ottawa | 65 | 52 | 62 | 80 | 80 | 95 |
| Castries | 113 | 76 | 66 | 90 | 114 | 134 |
| Difference | +48 | +24 | +5 | +10 | +34 | +38 |
| Jul – Dec | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|
| Ottawa | 92 | 87 | 87 | 89 | 70 | 72 |
| Castries | 216 | 291 | 224 | 246 | 243 | 149 |
| Difference | +124 | +205 | +137 | +157 | +172 | +77 |
Snowfall (cm)
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Ottawa | 44 | 41 | 31 | 8 | 0 | 0 | 0 | 0 | 0 | 2 | 16 | 43 |
| Castries | — | — | — | — | — | — | — | — | — | — | — | — |
| Difference | — | — | — | — | — | — | — | — | — | — | — | — |
| Jan – Jun | Jan | Feb | Mar | Apr | May | Jun |
|---|---|---|---|---|---|---|
| Ottawa | 44 | 41 | 31 | 8 | 0 | 0 |
| Castries | — | — | — | — | — | — |
| Difference | — | — | — | — | — | — |
| Jul – Dec | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|
| Ottawa | 0 | 0 | 0 | 2 | 16 | 43 |
| Castries | — | — | — | — | — | — |
| Difference | — | — | — | — | — | — |
Cloud cover (%) Ottawa runs higher most of the year
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Ottawa | 69 | 64 | 63 | 66 | 66 | 63 | 58 | 58 | 58 | 69 | 72 | 73 |
| Castries | 38 | 39 | 42 | 49 | 52 | 59 | 50 | 46 | 51 | 51 | 46 | 41 |
| Difference | -30 | -25 | -22 | -16 | -13 | -5 | -9 | -12 | -7 | -18 | -26 | -32 |
| Jan – Jun | Jan | Feb | Mar | Apr | May | Jun |
|---|---|---|---|---|---|---|
| Ottawa | 69 | 64 | 63 | 66 | 66 | 63 |
| Castries | 38 | 39 | 42 | 49 | 52 | 59 |
| Difference | -30 | -25 | -22 | -16 | -13 | -5 |
| Jul – Dec | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|
| Ottawa | 58 | 58 | 58 | 69 | 72 | 73 |
| Castries | 50 | 46 | 51 | 51 | 46 | 41 |
| Difference | -9 | -12 | -7 | -18 | -26 | -32 |
Relative humidity (%) Varies through the year
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Ottawa | 95 | 95 | 88 | 78 | 77 | 78 | 79 | 78 | 78 | 80 | 85 | 92 |
| Castries | 76 | 75 | 75 | 76 | 77 | 79 | 79 | 79 | 79 | 79 | 79 | 77 |
| Difference | -20 | -20 | -13 | -2 | +1 | — | — | +1 | +1 | -1 | -6 | -16 |
| Jan – Jun | Jan | Feb | Mar | Apr | May | Jun |
|---|---|---|---|---|---|---|
| Ottawa | 95 | 95 | 88 | 78 | 77 | 78 |
| Castries | 76 | 75 | 75 | 76 | 77 | 79 |
| Difference | -20 | -20 | -13 | -2 | +1 | — |
| Jul – Dec | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|
| Ottawa | 79 | 78 | 78 | 80 | 85 | 92 |
| Castries | 79 | 79 | 79 | 79 | 79 | 77 |
| Difference | — | +1 | +1 | -1 | -6 | -16 |
How both climates are changing
Both cities are warming. Each city has its own warming trend; see its trends page for the year-by-year detail. Ottawa trends → · Castries trends →
Methodology & sources
Ottawa
Temperature & precipitation — 1991–2020 normals computed from 30 years of daily observations at Ottawa Cda, a weather station, about 4 km from the city centre. The underlying daily records come from NOAA's global station network.
Cloud, humidity, wind & sunshine — modelled estimates from NASA POWER, NASA's satellite-and-reanalysis climatology. This is the standard global source for atmospheric variables, which are not measured at most weather stations.
Castries
Temperature — modelled for this location from ERA5-Land reanalysis, a ~9 km global grid, because no long-record weather station is close enough to use.
Precipitation — 1991–2020 normals computed from 10 years of daily observations at LE Lamentin, a weather station, about 66 km from the city centre. The underlying daily records come from NOAA's global station network.
Cloud, humidity, wind & sunshine — modelled estimates from NASA POWER, NASA's satellite-and-reanalysis climatology. This is the standard global source for atmospheric variables, which are not measured at most weather stations.
← change Ottawa · change Castries → · Ottawa page · Castries page