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Mostly more clear sky than cloud.

Cloud expected to cover about 30–65% of the sky for most the day. For example, during the day the sun is regularly behind cloud for short periods.

Duration in seconds between the most energetic waves at a specific point. The larger the period, the greater the amount of energy from the waves.

Water particles that fall from clouds to the ground. This can be as a liquid (rain) or solid (hail, snow).

Also see Duration of precipitation/rain.

Height and direction of the swell with the highest energy. This is sometimes called the dominant swell.

Forecast that expresses possible outcomes as a probability or percentage.

High probabilities don't guarantee an outcome. They indicate only that it's highly likely.

For example, when there is a 70% chance of rain today, it means for every 10 times we have a day with similar weather conditions to today, 7 times it will rain and 3 times it won't. By similar weather conditions we mean similar levels of moisture, temperatures, air movement and so on.

Most severe flood likely to happen at a location. Such a flood would result from the most severe combination of weather and water conditions.

Theoretical greatest depth of precipitation possible for a location with a defined:

  • storm area
  • storm duration
  • time of year.
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