Season by season
Dry season (December–June)
Drier, breezier and less humid, with clear views from Suicide Cliff and reliably starry nights. The trade winds blow onto the north and east coasts, so the sea at Banzai Cliff and Bird Island can be spectacular and the Grotto is sometimes closed by swell even in fine weather.
Wet season (July–November)
Hotter and wetter, with heavy showers and cloud that can hide the escarpment. The vegetation is lush, mornings are often fine and the sites are quieter. Steps and trails are slippery after rain — take particular care at the Grotto and on the path to Bird Island beach.
Sea conditions & typhoons
The north faces open ocean and has no protecting lagoon except along the San Roque shore, so swell matters more here than anywhere on the west coast. Operators cancel Grotto dives whenever surge is strong. Typhoons can occur in any month and are most likely from about August to November; after a storm, expect fallen trees and closed roads for a time.
Month by month
| Month | Avg high | Avg low | Rainfall | Crowds |
|---|---|---|---|---|
| January | 29°C | 23°C | 95 mm | Busy |
| February | 29°C | 23°C | 70 mm | Busy |
| March | 30°C | 23°C | 60 mm | Quiet |
| April | 31°C | 24°C | 65 mm | Quiet |
| May | 31°C | 25°C | 85 mm | Quiet |
| June | 31°C | 25°C | 125 mm | Quiet |
| July | 31°C | 25°C | 215 mm | Busy |
| August | 31°C | 24°C | 320 mm | Busy |
| September | 31°C | 24°C | 290 mm | Quiet |
| October | 31°C | 24°C | 270 mm | Quiet |
| November | 30°C | 24°C | 160 mm | Quiet |
| December | 29°C | 24°C | 110 mm | Busy |
Temperatures and rainfall are approximate long-term averages; individual years vary, and a single typhoon can change a month completely.
Festivals & events
- March–May: the clearest spell for stargazing from Banzai Cliff, and often the calmest seas for the Grotto
- June: the anniversary of the 15 June 1944 landings begins a period of remembrance across Saipan
- July: memorial services are held around 9 July, the day the battle ended, and Japanese, Okinawan and Korean groups visit the Marpi monuments
- July: Liberation Day on 4 July is Saipan’s main holiday — local families fill Pau Pau Beach
- August–November: the likeliest months for typhoons and for the Grotto to be closed by rough seas
Our advice
For the Grotto and for clear views, March to June is usually the best bet. Whenever you come, start early: the light on Bird Island is best in the morning, the heat builds by noon and tour vans arrive mid-morning. Save Banzai Cliff for late afternoon. Regional climate detail is on the when to go page.
