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Castries vs Seattle

Af Tropical rainforestCsb Warm-summer Mediterranean

Comparing Castries change · Seattle change

Bottom line

Castries is the warmer of the two — about 27°F on the annual average; Castries is the wetter, with 38 in more rain a year, and Castries the sunnier.

Warmer Castries 27°F on the year
Wetter Castries 38 in more a year
Sunnier Castries 19 pp less cloud
Colder winters Seattle 40°F colder nights

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 27°F on the annual average.

40°60°80° JanAprJulOct CastriesSeattle

Precipitation

Castries is the wetter — about 38 in more across the year.

PRECIPITATION (in) 0612 JanAprJulOct CastriesSeattle

Clear skies

Castries has the clearer skies — the higher line.

0%25%50%75%100% JanAprJulOct CastriesSeattle

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
JanFebMarAprMayJunJulAugSepOctNovDec
Castries808080828383838484838381
Seattle485054596671777872615247
Difference-32-30-26-22-16-12-6-6-12-23-30-34
Jan – JunJanFebMarAprMayJun
Castries808080828383
Seattle485054596671
Difference-32-30-26-22-16-12
Jul – DecJulAugSepOctNovDec
Castries838484838381
Seattle777872615247
Difference-6-6-12-23-30-34
Avg low (°F) Castries runs higher most of the year
JanFebMarAprMayJunJulAugSepOctNovDec
Castries787778798081818282828179
Seattle383840434953575754474137
Difference-40-40-38-36-32-28-24-25-28-35-40-42
Jan – JunJanFebMarAprMayJun
Castries787778798081
Seattle383840434953
Difference-40-40-38-36-32-28
Jul – DecJulAugSepOctNovDec
Castries818282828179
Seattle575754474137
Difference-24-25-28-35-40-42
Precipitation (in) Castries runs higher most of the year
JanFebMarAprMayJunJulAugSepOctNovDec
Castries4.532.63.54.55.38.511.58.89.79.65.9
Seattle5.83.84.23.21.91.50.611.63.96.35.7
Difference+1.3+0.8+1.6-0.4-2.6-3.8-7.9-10.5-7.2-5.8-3.2-0.2
Jan – JunJanFebMarAprMayJun
Castries4.532.63.54.55.3
Seattle5.83.84.23.21.91.5
Difference+1.3+0.8+1.6-0.4-2.6-3.8
Jul – DecJulAugSepOctNovDec
Castries8.511.58.89.79.65.9
Seattle0.611.63.96.35.7
Difference-7.9-10.5-7.2-5.8-3.2-0.2
Snowfall (in)
JanFebMarAprMayJunJulAugSepOctNovDec
Castries
Seattle1.82.20.400000000.21.7
Difference
Jan – JunJanFebMarAprMayJun
Castries
Seattle1.82.20.4000
Difference
Jul – DecJulAugSepOctNovDec
Castries
Seattle00000.21.7
Difference
Cloud cover (%) Seattle runs higher most of the year
JanFebMarAprMayJunJulAugSepOctNovDec
Castries383942495259504651514641
Seattle767274736966484851667575
Difference+37+33+32+24+17+8-2+2+15+28+35
Jan – JunJanFebMarAprMayJun
Castries383942495259
Seattle767274736966
Difference+37+33+32+24+17+8
Jul – DecJulAugSepOctNovDec
Castries504651514641
Seattle484851667575
Difference-2+2+15+28+35
Relative humidity (%) Seattle runs higher most of the year
JanFebMarAprMayJunJulAugSepOctNovDec
Castries767575767779797979797977
Seattle908785828080787677838990
Difference+15+13+10+6+2+1-1-2-1+4+10+13
Jan – JunJanFebMarAprMayJun
Castries767575767779
Seattle908785828080
Difference+15+13+10+6+2+1
Jul – DecJulAugSepOctNovDec
Castries797979797977
Seattle787677838990
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.

How we build these numbers →