Average temperature in Guam throughout the time of December is 5. Throughout the month you should see a high of 8 with lows around -1 degrees celsius. We have put some more detail below here:
| Month | Degrees Celsius |
|---|---|
| Temperature | 5 |
| High Temperature | 8 |
| Low Temperature | -1 |
Useful Links: Guam Weather: Average Weather & Yearly Climate