Castries weather in December

In December, Castries has daytime highs averaging 27 °C, nights around 24 °C, with 13 wet days, and a sea temperature of 28 °C. Figures are 1991–2020 climate normals.

  1. Jan 25°
  2. Feb 25°
  3. Mar 25°
  4. Apr 26°
  5. May 27°
  6. Jun 27°
  7. Jul 27°
  8. Aug 27°
  9. Sep 27°
  10. Oct 27°
  11. Nov 26°
  12. Dec 26°

Daily temperatures through December

21°26°30°18152229
Daily highDaily low Day of month on the horizontal axis. Highs peak at 27.8 °C and lows bottom out at 23.7 °C.

How December develops

Averages for the first, middle and last part of the month, from daily 1991–2020 normals. Chance of rain is the share of years in which that calendar day recorded more than 1 mm.

DaysAvg highAvg lowChance of rain
1–10 December27.5 °C24.3 °C47 %
11–20 December27.5 °C24.1 °C39 %
21–31 December27.3 °C23.9 °C41 %
0%50%100%151015202530
Chance of a wet day (over 1 mm) by date in December. Wettest date over the 30 years: December 2, at 63 %. Single dates are noisy — read the shape, not the spikes.

What to expect

Measure Typical December Share of the month
Days above 25 °C 31 of 31 100 %
Days above 30 °C 0 of 31 0 %
Days below 0 °C 0 of 31 0 %
Days with more than 1 mm rain 13 of 31 42 %

Conditions in December

MeasureAverage
Mean temperature 26 °C
Record high (1991–2020) 30 °C
Record low (1991–2020) 21 °C
Relative humidity 76 %
Wind speed 24 km/h
Cloud cover 42 %

Where Castries ranks in December

RankingPositionValue
The warmest places in North America in December40thof 5027 °C

December compared with the months around it

Month Avg high Rainfall Cloud
January 27.0 °C 36 mm 37 %
February 27.4 °C 25 mm 38 %
October 28.7 °C 119 mm 61 %
November 28.0 °C 103 mm 53 %
December 27.5 °C 46 mm 42 %

See all twelve months for Castries

Nearby destinations in December

Destination Avg high Wet days Sea
Castries 27 °C 13 28
Fort-de-France 27 °C 19 28
Kingstown 27 °C 12 28
Roseau 27 °C 14 28
Bridgetown 27 °C 12 28
Saint George's 27 °C 15 28
Basse-Terre 28 °C 14 28
Plymouth 27 °C 15 28
Saint John’s 27 °C 13 27

QuestionsDecember in Castries, answered

How warm is Castries in December?

Daily highs average 27 °C and nights fall to about 24 °C, a spread of 3.4 °C between afternoon and dawn. That makes December the 9th warmest month of the year here.

Does it rain much in Castries in December?

December averages 46 mm of rain, spread over about 13 of the 31 days — 42 % of the month. Cloud cover averages 42 % of the sky.

Is the sea warm enough to swim in December?

The sea averages 28 °C off Castries in December. Most people find water below 20 °C bracing and above 25 °C comfortable for a long swim; this figure is a monthly surface average, so a sheltered bay on a still afternoon can be warmer.

How long are the days in December?

Castries averages 11 hours between sunrise and sunset in December. Day length is computed from latitude and date, so it is exact rather than modelled — but it says nothing about how much of that time is sunny.

Data sources and method

Normal period
1991–2020
Dataset version
era5-1991-2020-scores1.1
Last processed

Measured values come from ERA5 reanalysis and are reproduced unchanged. Calculated by us: daylight hours, beach and comfort scores, monthly rankings, threshold day counts, chance of a wet day by date, ten-day averages within the month. Full formulas are on the methodology page.

Contains modified Copernicus Climate Change Service information 2026. Neither the European Commission nor ECMWF is responsible for any use that may be made of the Copernicus information or data it contains.