DAILY CLIMATE REPORT - issued daily: Detailed daily weather statistics (usually for yesterday), including temperature, precipitation, degree days, wind, humidity, sunrise/sunset, and record temperature data for the following day.
In Costa Rica the average annual temperature is around 21 to 27 degrees Celsius or 70 to 81 degrees Fahrenheit and the coolest months of the year are November, December and January. The months March through May are the hottest months of the year, so make sure you protect yourself from the sun.
May provides that 'in between time' that is just perfect! During a typical May in Cancun average daily temperatures are at exactly 90F with 17 of the 31 days exceeding 90 degrees and every single day, of course, exceeding eighty degrees. Minimum daily temperatures run at around 75F which is obviously still very pleasant, albeit a little too hot for the evening and night time.