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Castries vs San Francisco
Comparing Castries change · San Francisco change
Castries is the warmer of the two — about 13°C on the annual average; Castries is the wetter, with 1381 mm more rain a year, and Castries the sunnier.
How the seasons compare
The differences between Castries and San Francisco, in everyday terms.
Summers
Castries has much hotter summers
Castries: Warm
San Francisco: Mild
Winters
Castries has far milder winters
Castries: Stays warm
San Francisco: Cool
Rain & snow
Castries is much wetter
Castries: Very wet
San Francisco: Moderate rainfall
Sky
Castries is sunnier
Castries: Fairly sunny
San Francisco: Partly cloudy
Month-by-month charts
Temperature
Castries is the warmer of the two — about 13°C on the annual average.
Precipitation
Castries is the wetter — about 1381 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 |
| San Francisco | 14 | 16 | 17 | 17 | 18 | 19 | 19 | 20 | 21 | 21 | 18 | 14 |
| Difference | -12 | -11 | -10 | -10 | -10 | -9 | -9 | -9 | -8 | -8 | -10 | -13 |
| Jan – Jun | Jan | Feb | Mar | Apr | May | Jun |
|---|---|---|---|---|---|---|
| Castries | 27 | 27 | 27 | 28 | 28 | 28 |
| San Francisco | 14 | 16 | 17 | 17 | 18 | 19 |
| Difference | -12 | -11 | -10 | -10 | -10 | -9 |
| Jul – Dec | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|
| Castries | 28 | 29 | 29 | 29 | 28 | 27 |
| San Francisco | 19 | 20 | 21 | 21 | 18 | 14 |
| Difference | -9 | -9 | -8 | -8 | -10 | -13 |
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 |
| San Francisco | 8 | 9 | 9 | 10 | 11 | 12 | 12 | 13 | 13 | 12 | 10 | 8 |
| Difference | -17 | -16 | -16 | -16 | -16 | -15 | -15 | -15 | -15 | -15 | -17 | -18 |
| Jan – Jun | Jan | Feb | Mar | Apr | May | Jun |
|---|---|---|---|---|---|---|
| Castries | 26 | 25 | 25 | 26 | 27 | 27 |
| San Francisco | 8 | 9 | 9 | 10 | 11 | 12 |
| Difference | -17 | -16 | -16 | -16 | -16 | -15 |
| Jul – Dec | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|
| Castries | 27 | 28 | 28 | 28 | 27 | 26 |
| San Francisco | 12 | 13 | 13 | 12 | 10 | 8 |
| Difference | -15 | -15 | -15 | -15 | -17 | -18 |
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 |
| San Francisco | 112 | 111 | 80 | 41 | 18 | 5 | 0 | 2 | 3 | 24 | 66 | 121 |
| Difference | -2 | +35 | +14 | -49 | -96 | -129 | -216 | -290 | -221 | -223 | -177 | -28 |
| Jan – Jun | Jan | Feb | Mar | Apr | May | Jun |
|---|---|---|---|---|---|---|
| Castries | 113 | 76 | 66 | 90 | 114 | 134 |
| San Francisco | 112 | 111 | 80 | 41 | 18 | 5 |
| Difference | -2 | +35 | +14 | -49 | -96 | -129 |
| Jul – Dec | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|
| Castries | 216 | 291 | 224 | 246 | 243 | 149 |
| San Francisco | 0 | 2 | 3 | 24 | 66 | 121 |
| Difference | -216 | -290 | -221 | -223 | -177 | -28 |
Cloud cover (%) San Francisco 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 |
| San Francisco | 60 | 61 | 60 | 55 | 54 | 48 | 58 | 59 | 51 | 47 | 51 | 57 |
| Difference | +22 | +22 | +18 | +5 | +2 | -11 | +9 | +13 | — | -4 | +5 | +17 |
| Jan – Jun | Jan | Feb | Mar | Apr | May | Jun |
|---|---|---|---|---|---|---|
| Castries | 38 | 39 | 42 | 49 | 52 | 59 |
| San Francisco | 60 | 61 | 60 | 55 | 54 | 48 |
| Difference | +22 | +22 | +18 | +5 | +2 | -11 |
| Jul – Dec | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|
| Castries | 50 | 46 | 51 | 51 | 46 | 41 |
| San Francisco | 58 | 59 | 51 | 47 | 51 | 57 |
| Difference | +9 | +13 | — | -4 | +5 | +17 |
Relative humidity (%) Varies through 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 |
| San Francisco | 84 | 83 | 82 | 80 | 78 | 74 | 74 | 73 | 70 | 69 | 76 | 82 |
| Difference | +9 | +8 | +7 | +4 | +1 | -5 | -5 | -6 | -9 | -10 | -3 | +5 |
| Jan – Jun | Jan | Feb | Mar | Apr | May | Jun |
|---|---|---|---|---|---|---|
| Castries | 76 | 75 | 75 | 76 | 77 | 79 |
| San Francisco | 84 | 83 | 82 | 80 | 78 | 74 |
| Difference | +9 | +8 | +7 | +4 | +1 | -5 |
| Jul – Dec | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|
| Castries | 79 | 79 | 79 | 79 | 79 | 77 |
| San Francisco | 74 | 73 | 70 | 69 | 76 | 82 |
| Difference | -5 | -6 | -9 | -10 | -3 | +5 |
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 → · San Francisco 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.
San Francisco
Temperature & precipitation — the official 1991–2020 climate normals from NOAA's U.S. Climate Normals, measured at San Francisco Dwtn (NOAA GHCN station USW00023272), inside the city.
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 San Francisco → · Castries page · San Francisco page