Past IEM Features tagged: rates
The ASOS weather stations in the state record precipitation at one minute intervals. With this data, the featured chart presents the highest rainfall accumulation over a given number of minutes. This chart is useful from an engineering perspective as various structures are designed to handle a certain amount of water over a certain amount of time. There are numerous caveats to this chart including the fact that automated sensors struggle to accurately record these intense rates and the ASOS station includes an upward adjustment when rainfall rates get this high to account for under-catch. Having said all that, the chart does nicely illustrate the duration of the most intense thunderstorms. Since we are not situated against a mountain, storms have to move to maintain a source of energy, so the most rates are generally done within 30 minutes or so. Having sequential thunderstorms of this intensity is not going to happen as the atmosphere can not 'refill' its supply of water that quickly without the help of a mountain. There are some differences between the five sites plotted, but the differences are likely due to sensor / siting differences and not a physical explanation (perhaps). There is also only 15 years of data comprising this chart, so the sample size is a bit small.
Tags: precip rates