For forecast elements in "9-day Weather Forecast" other than PSR, the average accuracy for the next one to three days, four to seven days, and eight to nine days are about 90%, 85% and 80% respectively. The accuracy of forecast generally decreases while the error generally increases with forecast period.There are 5 categories of probability as follows:įor every 100 forecasts with a "high" probability, there are about 70 times or more with an average accumulated rainfall of 10 mm or above in actual observation.įor every 100 forecasts with a "medium high" probability, there are about 55 to 69 times with an average accumulated rainfall of 10 mm or above in actual observation.įor every 100 forecasts with a "medium" probability, there are about 45 to 54 times with an average accumulated rainfall of 10 mm or above in actual observation.įor every 100 forecasts with a "medium low" probability, there are about 30 to 44 times with an average accumulated rainfall of 10 mm or above in actual observation.įor every 100 forecasts with a "low" probability, there are about less than 30 times with an average accumulated rainfall of 10 mm or above in actual observation. around the mean daily rainfall in rainy season) or more on that day. The PSR forecast on each day indicates the probability of the accumulated rainfall generally over Hong Kong reaching 10 mm (i.e. The Probability of Significant Rain (PSR) forecast provides users with additional reference on rainfall amount and forecast trend for the coming 9 days.For detailed description of today's weather forecast, please refer to " Local Weather Forecast". "9-day Weather Forecast" provides general indications of the trends in weather for the coming 9 days.This middle 50% range (between 25th and 75th percentiles) is calculated based on the maximum/minimum temperature and relative humidity data within a 5-day period centred on that day in the 30 years from 1991 to 2020.This service is based on data and products of the European Centre for Medium-range Weather Forecasts (ECMWF). It forecasts the MSLP in hecto Pascals (hPa) for the top of that hour initially in 3 hourly intervals, then 6 hourly. The Mean Sea Level Pressure (MSLP) is direct model output from Numerical Weather Prediction models but is a guideline only. Minus zero (-0) indicates values between 0 to -0.5☌. It forecasts air temperature on land and over sea in ☌ for the top of each hour, 3 hourly and finally 6 hourly intervals up to 7 days. The temperature is direct model output from Numerical Weather Prediction models but is a guideline only. However, in the text forecast below, it is described as where it is blowing from. The wind arrow tip points in the direction the wind is blowing and the tail length indicates wind strength. It forecasts the strength of the wind (in knots and km/h) at 10m for the top of each hour, in hourly, then 3 hourly and finally 6 hourly intervals up to 7 days. The wind is direct model output from Numerical Weather Prediction models but is a guideline only. This service is based on data and products of the European Centre for Medium-range Weather Forecasts (ECMWF) It forecasts how much rain will fall (in mm) hourly during the previous hour (accumulations), then in 3 hourly and finally 6 hourly accumulations up to 7 days. Rain refers to precipitation, which can be rain, sleet or snow. The rainfall forecast is direct model output from Numerical Weather Prediction models but is a guideline only. Met Éireann forecasters manually produce the weather icons for midday and midnight to reflect the predicted major weather type for these times. They are artefacts (false echoes) of rainfall radar systems and should be ignored. Dublin), bright bands and spokes may also be present in images. Initially, they are red but change to orange and then yellow after a period, then disappear © Met Office ATDNet. Lightning strikes, when they occur, are displayed as a cross. Accumulations can refer to rainfall only. Latest Rainfall Radar showing live precipitation and the last 90 minutes precipitation over Ireland, updated every 5 minutes. Find out more about the Shannon weather radar replacement here. Changes can be expected in the radar service over the South and West of the country. Cork and two UK Met Office weather radars in Belfast and Wales, when available. During this time, the ‘Latest radar’ image shows combined information from the Dublin weather radar, a temporary weather radar operating from Co. Shannon radar undergoing replacement: From mid-May 2023 and over the summer, the Shannon weather radar is being replaced by a new weather radar system. Peer-reviewed journal articles by Met Éireann staff members Past Weather Agrometeorological Bulletins
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