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Castries vs Seattle
Comparing Castries change · Seattle change
Castries is the warmer of the two — about 15°C on the annual average; Castries is the wetter, with 963 mm more rain a year, and Castries the sunnier.
How the seasons compare
The differences between Castries and Seattle, in everyday terms.
Summers
Castries has hotter summers
Castries: Warm
Seattle: Mild
Winters
Castries has far milder winters
Castries: Stays warm
Seattle: Chilly
Rain & snow
Castries is wetter
Castries: Very wet
Seattle: Moderate rainfall
Sky
Castries is sunnier
Castries: Fairly sunny
Seattle: Often cloudy
Month-by-month charts
Temperature
Castries is the warmer of the two — about 15°C on the annual average.
Precipitation
Castries is the wetter — about 963 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 |
| Seattle | 9 | 10 | 12 | 15 | 19 | 22 | 25 | 25 | 22 | 16 | 11 | 8 |
| Difference | -18 | -16 | -15 | -12 | -9 | -7 | -3 | -3 | -7 | -13 | -17 | -19 |
| Jan – Jun | Jan | Feb | Mar | Apr | May | Jun |
|---|---|---|---|---|---|---|
| Castries | 27 | 27 | 27 | 28 | 28 | 28 |
| Seattle | 9 | 10 | 12 | 15 | 19 | 22 |
| Difference | -18 | -16 | -15 | -12 | -9 | -7 |
| Jul – Dec | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|
| Castries | 28 | 29 | 29 | 29 | 28 | 27 |
| Seattle | 25 | 25 | 22 | 16 | 11 | 8 |
| Difference | -3 | -3 | -7 | -13 | -17 | -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 |
| Seattle | 3 | 3 | 4 | 6 | 9 | 12 | 14 | 14 | 12 | 8 | 5 | 3 |
| Difference | -22 | -22 | -21 | -20 | -18 | -15 | -13 | -14 | -16 | -19 | -22 | -23 |
| Jan – Jun | Jan | Feb | Mar | Apr | May | Jun |
|---|---|---|---|---|---|---|
| Castries | 26 | 25 | 25 | 26 | 27 | 27 |
| Seattle | 3 | 3 | 4 | 6 | 9 | 12 |
| Difference | -22 | -22 | -21 | -20 | -18 | -15 |
| Jul – Dec | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|
| Castries | 27 | 28 | 28 | 28 | 27 | 26 |
| Seattle | 14 | 14 | 12 | 8 | 5 | 3 |
| Difference | -13 | -14 | -16 | -19 | -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 |
| Seattle | 147 | 96 | 106 | 81 | 48 | 37 | 15 | 25 | 41 | 99 | 160 | 145 |
| Difference | +34 | +20 | +40 | -9 | -66 | -97 | -201 | -267 | -183 | -147 | -82 | -4 |
| Jan – Jun | Jan | Feb | Mar | Apr | May | Jun |
|---|---|---|---|---|---|---|
| Castries | 113 | 76 | 66 | 90 | 114 | 134 |
| Seattle | 147 | 96 | 106 | 81 | 48 | 37 |
| Difference | +34 | +20 | +40 | -9 | -66 | -97 |
| Jul – Dec | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|
| Castries | 216 | 291 | 224 | 246 | 243 | 149 |
| Seattle | 15 | 25 | 41 | 99 | 160 | 145 |
| Difference | -201 | -267 | -183 | -147 | -82 | -4 |
Snowfall (cm)
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Castries | — | — | — | — | — | — | — | — | — | — | — | — |
| Seattle | 5 | 6 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 1 | 4 |
| Difference | — | — | — | — | — | — | — | — | — | — | — | — |
| Jan – Jun | Jan | Feb | Mar | Apr | May | Jun |
|---|---|---|---|---|---|---|
| Castries | — | — | — | — | — | — |
| Seattle | 5 | 6 | 1 | 0 | 0 | 0 |
| Difference | — | — | — | — | — | — |
| Jul – Dec | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|
| Castries | — | — | — | — | — | — |
| Seattle | 0 | 0 | 0 | 0 | 1 | 4 |
| Difference | — | — | — | — | — | — |
Cloud cover (%) Seattle 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 |
| Seattle | 76 | 72 | 74 | 73 | 69 | 66 | 48 | 48 | 51 | 66 | 75 | 75 |
| Difference | +37 | +33 | +32 | +24 | +17 | +8 | -2 | +2 | — | +15 | +28 | +35 |
| Jan – Jun | Jan | Feb | Mar | Apr | May | Jun |
|---|---|---|---|---|---|---|
| Castries | 38 | 39 | 42 | 49 | 52 | 59 |
| Seattle | 76 | 72 | 74 | 73 | 69 | 66 |
| Difference | +37 | +33 | +32 | +24 | +17 | +8 |
| Jul – Dec | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|
| Castries | 50 | 46 | 51 | 51 | 46 | 41 |
| Seattle | 48 | 48 | 51 | 66 | 75 | 75 |
| Difference | -2 | +2 | — | +15 | +28 | +35 |
Relative humidity (%) Seattle 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 |
| Seattle | 90 | 87 | 85 | 82 | 80 | 80 | 78 | 76 | 77 | 83 | 89 | 90 |
| Difference | +15 | +13 | +10 | +6 | +2 | +1 | -1 | -2 | -1 | +4 | +10 | +13 |
| Jan – Jun | Jan | Feb | Mar | Apr | May | Jun |
|---|---|---|---|---|---|---|
| Castries | 76 | 75 | 75 | 76 | 77 | 79 |
| Seattle | 90 | 87 | 85 | 82 | 80 | 80 |
| Difference | +15 | +13 | +10 | +6 | +2 | +1 |
| Jul – Dec | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|
| Castries | 79 | 79 | 79 | 79 | 79 | 77 |
| Seattle | 78 | 76 | 77 | 83 | 89 | 90 |
| Difference | -1 | -2 | -1 | +4 | +10 | +13 |
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 → · Seattle trends →
Seattle from Csb to Csa.
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.
Seattle
Temperature & precipitation — the official 1991–2020 climate normals from NOAA's U.S. Climate Normals, measured at Seattle Tacoma AP (NOAA GHCN station USW00024233), about 18 km from the city centre.
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 Seattle → · Castries page · Seattle page