Search results
Results From The WOW.Com Content Network
The Quantitative Precipitation Forecast (abbreviated QPF) is the expected amount of liquid precipitation accumulated over a specified time over a specified area. [115] A QPF will be specified when a measurable precipitation type reaching a minimum threshold is forecast for any hour during a QPF valid period.
The probability of precipitation can also be expressed using descriptive terms instead of numerical values. For instance, the NWS might describe a precipitation forecast with terms such as "slight chance" meaning 20% certainty and "scattered" meaning 30–50% areal coverage. [10] The precise meaning of these terms varies. [11]
Within the United States, the Hydrometeorological Prediction Center, [20] River Forecast Centers, [1] and local forecast offices within the National Weather Service create precipitation forecasts for up to five days in the future, [21] forecasting amounts equal to or greater than 0.01 inches (0.25 mm). Starting in the mid-to-late 1990s, QPFs ...
Cornish said the concept is plain and simple: "It is the probability that at least 0.01 of an inch of precipitation will fall on your rooftop if you live in the forecast area.
Precipitation is measured using a rain gauge, and more recently remote sensing techniques such as a weather radar. When classified according to the rate of precipitation, rain can be divided into categories. Light rain describes rainfall which falls at a rate of between a trace and 2.5 millimetres (0.098 in) per hour. Moderate rain describes ...
The British Royal Navy, working with the Met Office, has its own specialist branch of weather observers and forecasters, as part of the Hydrographic and Meteorological (HM) specialisation, who monitor and forecast operational conditions across the globe, to provide accurate and timely weather and oceanographic information to submarines, ships ...
The National Weather Service is forecasting a minor to moderate rain event in Los Angeles and Ventura counties next week from Tuesday through Thursday, with a quarter of an inch to an inch of rain ...
Weather refers to day-to-day temperature, precipitation, and other atmospheric conditions, whereas climate is the term for the averaging of atmospheric conditions over longer periods of time. [4] When used without qualification, "weather" is generally understood to mean the weather of Earth.