| Guanacaste | Low Temp | High Temp | Total Precipitation | Days with Rain |
| Jan | 69.1 | 92.1 | .04 | 1 |
| Feb | 70.0 | 93.9 | .07 | 0 |
| Mar | 71.1 | 95.7 | .21 | 0 |
| Apr | 73.0 | 96.8 | .69 | 3 |
| May | 74.3 | 93.2 | 7.81 | 15 |
| June | 73.8 | 89.8 | 9.64 | 23 |
| July | 73.0 | 90.0 | 5.80 | 18 |
| Aug | 72.7 | 89.8 | 8.10 | 19 |
| Sept | 72.1 | 88.2 | 14.41 | 28 |
| Oct | 72.0 | 88.0 | 12.50 | 25 |
| Nov | 70.9 | 89.1 | 4.06 | 12 |
| Dec | 70.0 | 90.7 | .44 | 4 |
Typical weather in Costa Rica, barring unusual tropical depressions, means that "days with rain" will include sunshine in the morning with clouds and rain in the afternoon and nighttime.
