Tropical Cyclone Wind Speed Probability Products

Product Description Document

Wind speed probability products are designed to answer these questions:

  1. What are the chances of experiencing these winds?
  2. When is the event most likely to start?

In the images below, there is a 20% chance of 34 kt winds on the Big Island and parts of Maui County through the next 108 hours. There is less than a 5% chance of 50 kt winds in the same time period. These probabilities will change with each updated forecast. They do not indicate the probability over the life time of the storm...only for the 120 hours covered by the current forecast.

Example of Prob 34
Example of Prob 50

What the numbers mean

We welcome any and all feedback on these products. Please e-mail your comments to

The examples below show how these graphics will look during an actual forecast.

Wind at least 39 MPH (34 KTS)
Winds at least 58 MPH (50 KTS)
Winds at least 74 MPH (64 KTS)