World Resorts Costa Rica Jaco Weather

Jaco weather in September

Weather in Jaco: September

Average day temperature: 81.9°F
Average night temperature: 78.1°F
Sea water temperature: 83.8°F
Number of sunny days: 0 days
Day length: 12.0 - 12.3 hours
Number of rainy days: 21 days
Precipitation totals: 10.8 in.

Air temperature in September, °F

Show year:
2025
2024
2023

The highest day temperature during September of 2025 was 84°F. At the same time the lowest night temperature was 77°F. Daily and nightly averages during September were 81.7°F and 78.2°F.

Sea water temperature in Jaco in September, °F

Show year:
2025
2024
2023

The average sea water temperature in September of 2025 was 83.7°F. The highest and lowest sea temperatures during the month were 84.4°F and 83.3°F.

Sunny, partly cloudy and cloudy days

Mostly all days in September are cloudy but sunny and partly cloudy days are also possible.

Precipitation total in September, in.

Precipitation total value in Jaco in September is 10.8 in. It makes september one of the most rainy months of the year.

Wind speed in September, mph

The average wind speed value in September is 4.5 mph It makes September one of the least windy months of the year.

Average sunny hours

This chart shows average number of hours during the day when sunlight can reach the ground. It depends on day length and cloudiness during the day. The average number of sunny hours in September is: 3.7.

Best time for vacation in Jaco

Sunniest months:
February 11 days
March 10 days
January 7 days
Warmest months:
April 85.2 °F
March 85.1 °F
February 84.7 °F
Warmest sea temp:
April 85.6 °F
May 85.4 °F
March 85.3 °F
Coldest months:
November 80.5 °F
October 81.2 °F
August 81.7 °F
Rainiest months:
August 24 days
July 22 days
June 22 days
Windiest months:
February 5.2 mph
March 5.1 mph
April 4.8 mph

Jaco on a weather map

Jaco
+77°F
W 5 mph
Feels like: +81°F
Precip.: 100%
Places in Costa Rica:
Name
°F
+57°F
+77°F
+73°F
+72°F
+73°F
+73°F
+75°F
+54°F
+79°F
+75°F
+73°F
+57°F
24 Hours Forecast
Jaco
Local time: 00:53
December 05, friday
0300
75°F
SW
6 mph
0600
75°F
SW
6 mph
0900
81°F
W
3 mph
1200
81°F
N
6 mph
1500
81°F
N
6 mph
1800
79°F
NW
6 mph
2100
77°F
W
5 mph
December 06, saturday
0000
77°F
W
4 mph
Units of measurement: °C / °F