Originally Posted by
evergrn
I know you can’t predict anything but I wonder how many decent beach/pool days we can expect in worst-case scenario on a 5-day trip in late Aug.
Worst case scenario over a 5 day period is five days of disruption with a slow moving storm. Two friends of mine decided to take a cruise to Okinawa many years ago and spent most of the week heaved to at some distance from land (unable to dock) in heavy weather. In the end, they had no time to visit the islands that they had hoped to see, with the added frustration that they spent a day at the airport in fine weather, waiting for severely delayed flights home. IIRC, the storm was not exceptionally severe as measured by wind speed, rainfall, and storm surge. But it moved slowly.
- Transportation boats / ferries - Will keep running as long as sea conditions permit. It can be tricky to dock on some islands, so these services are more easily disrupted.
- Pleasure boats / snorkeling tours - Pretty certain to be cancelled as soon as wind and sea conditions make them uncomfortable (which doesn't take much)
- Beaches - Will be not worth visiting in windy / rainy conditions as the storm approaches. Completely off limits if low pressure coincides with high tides and risk of storm surge
- Pools - Likely to be stay unless there's an electrical storm nearby
My understanding is that the speed that a weather system travels is not dependent on the severity of the system (in pressure, wind speed, etc.) so the length of disruption is hard to predict, even when the storm is overhead - let alone when you're talking about a hypothetical storm sometime in August this year or next.
You can get some idea of the uncertainty from the cones that are drawn on typhoon warning maps - The meteorologists will predict with >70% accuracy that a storm will be somewhere in that cone in two or three days time, but some of the time it will defy expectations and go outside the cone or just stay where it is.
The "strength" of a tropical storm can be measured in pressure, wind speed, or storm surge (effect on sea level). The potential for damage can depend on the tides and the physical geography of the location where the storm lands. The duration of damaging rain, wind, and pressure effects (which can raise sea levels) depends on the speed that the storm is moving.