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Castries vs Boston
Comparing Castries change · Boston change
Castries is the warmer of the two — about 29°F on the annual average; Castries is the wetter, with 34 in more rain a year, and Castries the sunnier.
How the seasons compare
The differences between Castries and Boston, in everyday terms.
Summers
Summers are nearly the same
Castries: Warm
Boston: Warm
Winters
Castries has far milder winters
Castries: Stays warm
Boston: Cold
Rain & snow
Castries is wetter
Castries: Very wet
Boston: Wet
Sky
Castries is sunnier
Castries: Fairly sunny
Boston: Partly cloudy
Month-by-month charts
Temperature
Castries is the warmer of the two — about 29°F on the annual average.
Precipitation
Castries is the wetter — about 34 in 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 (°F) Castries runs higher most of the year
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Castries | 80 | 80 | 80 | 82 | 83 | 83 | 83 | 84 | 84 | 83 | 83 | 81 |
| Boston | 37 | 39 | 46 | 56 | 67 | 76 | 82 | 80 | 73 | 62 | 52 | 42 |
| Difference | -43 | -41 | -35 | -25 | -16 | -7 | -1 | -3 | -11 | -21 | -31 | -39 |
| Jan – Jun | Jan | Feb | Mar | Apr | May | Jun |
|---|---|---|---|---|---|---|
| Castries | 80 | 80 | 80 | 82 | 83 | 83 |
| Boston | 37 | 39 | 46 | 56 | 67 | 76 |
| Difference | -43 | -41 | -35 | -25 | -16 | -7 |
| Jul – Dec | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|
| Castries | 83 | 84 | 84 | 83 | 83 | 81 |
| Boston | 82 | 80 | 73 | 62 | 52 | 42 |
| Difference | -1 | -3 | -11 | -21 | -31 | -39 |
Avg low (°F) Castries runs higher most of the year
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Castries | 78 | 77 | 78 | 79 | 80 | 81 | 81 | 82 | 82 | 82 | 81 | 79 |
| Boston | 23 | 25 | 31 | 41 | 50 | 60 | 66 | 65 | 58 | 48 | 38 | 29 |
| Difference | -55 | -53 | -47 | -38 | -30 | -21 | -15 | -17 | -24 | -34 | -43 | -50 |
| Jan – Jun | Jan | Feb | Mar | Apr | May | Jun |
|---|---|---|---|---|---|---|
| Castries | 78 | 77 | 78 | 79 | 80 | 81 |
| Boston | 23 | 25 | 31 | 41 | 50 | 60 |
| Difference | -55 | -53 | -47 | -38 | -30 | -21 |
| Jul – Dec | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|
| Castries | 81 | 82 | 82 | 82 | 81 | 79 |
| Boston | 66 | 65 | 58 | 48 | 38 | 29 |
| Difference | -15 | -17 | -24 | -34 | -43 | -50 |
Precipitation (in) Castries runs higher most of the year
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Castries | 4.5 | 3 | 2.6 | 3.5 | 4.5 | 5.3 | 8.5 | 11.5 | 8.8 | 9.7 | 9.6 | 5.9 |
| Boston | 3.4 | 3.2 | 4.2 | 3.6 | 3.3 | 3.9 | 3.3 | 3.2 | 3.6 | 4 | 3.7 | 4.3 |
| Difference | -1.1 | +0.2 | +1.6 | +0.1 | -1.2 | -1.4 | -5.2 | -8.2 | -5.3 | -5.7 | -5.9 | -1.6 |
| Jan – Jun | Jan | Feb | Mar | Apr | May | Jun |
|---|---|---|---|---|---|---|
| Castries | 4.5 | 3 | 2.6 | 3.5 | 4.5 | 5.3 |
| Boston | 3.4 | 3.2 | 4.2 | 3.6 | 3.3 | 3.9 |
| Difference | -1.1 | +0.2 | +1.6 | +0.1 | -1.2 | -1.4 |
| Jul – Dec | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|
| Castries | 8.5 | 11.5 | 8.8 | 9.7 | 9.6 | 5.9 |
| Boston | 3.3 | 3.2 | 3.6 | 4 | 3.7 | 4.3 |
| Difference | -5.2 | -8.2 | -5.3 | -5.7 | -5.9 | -1.6 |
Snowfall (in)
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Castries | — | — | — | — | — | — | — | — | — | — | — | — |
| Boston | 14.3 | 14.4 | 9 | 1.6 | 0 | 0 | 0 | 0 | 0 | 0.2 | 0.7 | 9 |
| Difference | — | — | — | — | — | — | — | — | — | — | — | — |
| Jan – Jun | Jan | Feb | Mar | Apr | May | Jun |
|---|---|---|---|---|---|---|
| Castries | — | — | — | — | — | — |
| Boston | 14.3 | 14.4 | 9 | 1.6 | 0 | 0 |
| Difference | — | — | — | — | — | — |
| Jul – Dec | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|
| Castries | — | — | — | — | — | — |
| Boston | 0 | 0 | 0 | 0.2 | 0.7 | 9 |
| Difference | — | — | — | — | — | — |
Cloud cover (%) Boston 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 |
| Boston | 63 | 62 | 62 | 64 | 65 | 63 | 57 | 56 | 55 | 60 | 62 | 63 |
| Difference | +25 | +23 | +20 | +14 | +13 | +5 | +8 | +9 | +4 | +9 | +16 | +22 |
| Jan – Jun | Jan | Feb | Mar | Apr | May | Jun |
|---|---|---|---|---|---|---|
| Castries | 38 | 39 | 42 | 49 | 52 | 59 |
| Boston | 63 | 62 | 62 | 64 | 65 | 63 |
| Difference | +25 | +23 | +20 | +14 | +13 | +5 |
| Jul – Dec | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|
| Castries | 50 | 46 | 51 | 51 | 46 | 41 |
| Boston | 57 | 56 | 55 | 60 | 62 | 63 |
| Difference | +8 | +9 | +4 | +9 | +16 | +22 |
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 |
| Boston | 88 | 87 | 83 | 80 | 79 | 79 | 74 | 73 | 74 | 78 | 82 | 86 |
| Difference | +12 | +12 | +9 | +3 | +1 | — | -4 | -6 | -4 | -1 | +2 | +9 |
| Jan – Jun | Jan | Feb | Mar | Apr | May | Jun |
|---|---|---|---|---|---|---|
| Castries | 76 | 75 | 75 | 76 | 77 | 79 |
| Boston | 88 | 87 | 83 | 80 | 79 | 79 |
| Difference | +12 | +12 | +9 | +3 | +1 | — |
| Jul – Dec | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|
| Castries | 79 | 79 | 79 | 79 | 79 | 77 |
| Boston | 74 | 73 | 74 | 78 | 82 | 86 |
| Difference | -4 | -6 | -4 | -1 | +2 | +9 |
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 → · Boston 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.
Boston
Temperature & precipitation — the official 1991–2020 climate normals from NOAA's U.S. Climate Normals, measured at Boston (NOAA GHCN station USW00014739), about 4 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 Boston → · Castries page · Boston page