Osa Peninsula Weather

Today's Forecast for Carate

Rainfall Data for Lookout Inn and Carate

Terry Conroy and Katya Ballanero Quesada at the Lookout Inn have been measuring and recording daily precipitation since July 1998.   Below are a climatological summary and a few comments, by Steven Worley.

Below is a chart that shows the minimum, maximum, and mean (average) precipitation by month at the Lookout Inn.  September, October, and November are the wettest months and January, February, and March are the driest, on average.  There is huge variability, for example the driest November had 11.9 (2002) inches of rain and the wettest had 88.8 (1999) inches.

Monthly total rainfall (inches) at Lookout Inn (Carate) Costa Rica. 
Daily measurements collected by Terry Conroy and Katya of Lookout Inn

1998-2009 Minimum   1998-2009 Average   1998-2009 Maximum

If we look at the mean precipitation and the expected variability around that value we see, on average, the wettest month is October and the driest is February.  Keep in mind these are statistics for a 12-year period and any particular year is more difficult to predict.

The chart below shows the annual amount of rain for the full period of record (1998 is not shown since the data collection begins in July). 2009 (164 inches) was the driest year and 2004 (373 inches) was the wettest. What causes this? Possible large scale forcing is related to the position of the Inter-tropical Convergence Zone, the strength of El Nino or La Nina, and the activity of Atlantic Hurricanes or Pacific Typhoons. More work needs to be done on this and it is made difficult with the short, 12-year, data record.

Yellow indicates monthly estimates provided by Terry of Lookout Inn