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Castries vs Belfast
Comparing Castries change · Belfast change
Castries is the warmer of the two — about 17°C on the annual average; Castries is the wetter, with 981 mm more rain a year, and Castries the sunnier.
How the seasons compare
The differences between Castries and Belfast, in everyday terms.
Summers
Castries has far hotter summers
Castries: Warm
Belfast: Mild
Winters
Castries has far milder winters
Castries: Stays warm
Belfast: Chilly
Rain & snow
Castries is wetter
Castries: Very wet
Belfast: Moderate rainfall
Sky
Castries is far sunnier
Castries: Fairly sunny
Belfast: Often grey
Month-by-month charts
Temperature
Castries is the warmer of the two — about 17°C on the annual average.
Precipitation
Castries is the wetter — about 981 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 | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Castries | 27 | 27 | 27 | 28 | 28 | 28 | 28 | 29 | 29 | 29 | 28 | 27 |
| Belfast | 8 | 9 | 10 | 13 | 15 | 18 | 19 | 19 | 17 | 14 | 10 | 8 |
| Difference | -19 | -18 | -17 | -15 | -13 | -11 | -9 | -10 | -12 | -15 | -18 | -19 |
| Jan – Jun | Jan | Feb | Mar | Apr | May | Jun |
|---|---|---|---|---|---|---|
| Castries | 27 | 27 | 27 | 28 | 28 | 28 |
| Belfast | 8 | 9 | 10 | 13 | 15 | 18 |
| Difference | -19 | -18 | -17 | -15 | -13 | -11 |
| Jul – Dec | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|
| Castries | 28 | 29 | 29 | 29 | 28 | 27 |
| Belfast | 19 | 19 | 17 | 14 | 10 | 8 |
| Difference | -9 | -10 | -12 | -15 | -18 | -19 |
Avg low (°C) Castries runs higher most of the year
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Castries | 26 | 25 | 25 | 26 | 27 | 27 | 27 | 28 | 28 | 28 | 27 | 26 |
| Belfast | 2 | 2 | 3 | 5 | 7 | 10 | 12 | 12 | 10 | 7 | 5 | 3 |
| Difference | -23 | -23 | -22 | -21 | -19 | -17 | -16 | -16 | -18 | -20 | -22 | -23 |
| Jan – Jun | Jan | Feb | Mar | Apr | May | Jun |
|---|---|---|---|---|---|---|
| Castries | 26 | 25 | 25 | 26 | 27 | 27 |
| Belfast | 2 | 2 | 3 | 5 | 7 | 10 |
| Difference | -23 | -23 | -22 | -21 | -19 | -17 |
| Jul – Dec | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|
| Castries | 27 | 28 | 28 | 28 | 27 | 26 |
| Belfast | 12 | 12 | 10 | 7 | 5 | 3 |
| Difference | -16 | -16 | -18 | -20 | -22 | -23 |
Precipitation (mm) Castries runs higher most of the year
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Castries | 113 | 76 | 66 | 90 | 114 | 134 | 216 | 291 | 224 | 246 | 243 | 149 |
| Belfast | 89 | 73 | 73 | 64 | 68 | 74 | 77 | 88 | 75 | 98 | 106 | 95 |
| Difference | -24 | -3 | +7 | -25 | -46 | -59 | -139 | -204 | -149 | -148 | -137 | -54 |
| Jan – Jun | Jan | Feb | Mar | Apr | May | Jun |
|---|---|---|---|---|---|---|
| Castries | 113 | 76 | 66 | 90 | 114 | 134 |
| Belfast | 89 | 73 | 73 | 64 | 68 | 74 |
| Difference | -24 | -3 | +7 | -25 | -46 | -59 |
| Jul – Dec | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|
| Castries | 216 | 291 | 224 | 246 | 243 | 149 |
| Belfast | 77 | 88 | 75 | 98 | 106 | 95 |
| Difference | -139 | -204 | -149 | -148 | -137 | -54 |
Cloud cover (%) Belfast runs higher most of the year
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Castries | 38 | 39 | 42 | 49 | 52 | 59 | 50 | 46 | 51 | 51 | 46 | 41 |
| Belfast | 79 | 79 | 78 | 76 | 73 | 77 | 78 | 77 | 76 | 78 | 79 | 78 |
| Difference | +40 | +40 | +37 | +27 | +21 | +18 | +28 | +30 | +25 | +27 | +32 | +38 |
| Jan – Jun | Jan | Feb | Mar | Apr | May | Jun |
|---|---|---|---|---|---|---|
| Castries | 38 | 39 | 42 | 49 | 52 | 59 |
| Belfast | 79 | 79 | 78 | 76 | 73 | 77 |
| Difference | +40 | +40 | +37 | +27 | +21 | +18 |
| Jul – Dec | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|
| Castries | 50 | 46 | 51 | 51 | 46 | 41 |
| Belfast | 78 | 77 | 76 | 78 | 79 | 78 |
| Difference | +28 | +30 | +25 | +27 | +32 | +38 |
Relative humidity (%) Belfast runs higher most of the year
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Castries | 76 | 75 | 75 | 76 | 77 | 79 | 79 | 79 | 79 | 79 | 79 | 77 |
| Belfast | 90 | 90 | 89 | 86 | 85 | 85 | 86 | 87 | 88 | 88 | 90 | 91 |
| Difference | +15 | +15 | +14 | +10 | +7 | +7 | +8 | +8 | +9 | +9 | +11 | +14 |
| Jan – Jun | Jan | Feb | Mar | Apr | May | Jun |
|---|---|---|---|---|---|---|
| Castries | 76 | 75 | 75 | 76 | 77 | 79 |
| Belfast | 90 | 90 | 89 | 86 | 85 | 85 |
| Difference | +15 | +15 | +14 | +10 | +7 | +7 |
| Jul – Dec | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|
| Castries | 79 | 79 | 79 | 79 | 79 | 77 |
| Belfast | 86 | 87 | 88 | 88 | 90 | 91 |
| Difference | +8 | +8 | +9 | +9 | +11 | +14 |
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. Castries trends → · Belfast trends →
Both cities' Köppen climate types are projected to hold steady through 2099 (SSP2-4.5).
Methodology & sources
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.
Belfast
Temperature & precipitation — 1991–2020 normals computed from 29 years of daily observations at Stormont Castle, a weather station, about 6 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 Castries · change Belfast → · Castries page · Belfast page