Measurements:
°C
°F
CURRENT WEATHER
03:48
Alajuela
66°F
SW 3 mph
Feels like: 66°F
Precip: 49%
World Resorts Costa Rica Alajuela Weather

7 Day Weather Forecast

09.07
mon
DAY
78°F
E 4 mph
precip
67%
NIGHT
68°F
SW 4 mph
precip
40%
09.08
tue
DAY
88°F
W 1 mph
precip
57%
NIGHT
68°F
SW 4 mph
precip
16%
09.09
wed
DAY
82°F
SW 2 mph
precip
17%
NIGHT
68°F
SW 5 mph
precip
38%
09.10
thu
DAY
86°F
SW 6 mph
precip
11%
NIGHT
66°F
SW 4 mph
precip
27%
09.11
fri
DAY
80°F
E 1 mph
precip
62%
NIGHT
68°F
SW 3 mph
precip
29%
09.12
sat
DAY
80°F
NE 2 mph
precip
75%
NIGHT
68°F
SW 2 mph
precip
37%
09.13
sun
DAY
78°F
NE 3 mph
precip
73%
NIGHT
68°F
SW 2 mph
precip
58%

Alajuela Sea Water Temperature in September, °F

Select Year: 2025 2024 2023

The average sea surface temperature in September 2025 for Alajuela was 28.7°F. The maximum and minimum values were 28.4°F and 29.0°F respectively.

Alajuela on the Weather Map

Best Time to Visit Alajuela
The most sunny months:
February 16 days
March 16 days
January 15 days
The most warm months:
March 87.3 °F
April 86.3 °F
February 85.5 °F
Warmest sea temperature:
April 89.1 °F
May 88.9 °F
March 88.6 °F
The most cold months:
October 78.7 °F
November 78.8 °F
September 80.0 °F
The most rainy months:
September 25 days
October 25 days
June 24 days
The most windy months:
February 6 mph
January 6 mph
March 6 mph
more details