Understanding and Communicating Future Flood Damages Using Weather Typing

As the science of meteorology progresses, meteorologists are given new tools to aid in the weather forecasting process. One of these tools is known as “weather typing”, which allows for the bypassing of complex processes such as numerical model weather prediction which can result in rainfall amount and location uncertainty. By assigning a potential flood damage or loss value to a specific weather type, meteorologists, emergency managers and other professionals are able to infer the flood threat a certain weather type brings. Flood damage by weather type is derived using historical data. Daily weather maps are assigned one of twelve weather types, defined using mid-level winds, sea level pressure, and precipitable water.  Combined with property damage data dating back to 1996,  a relationship between weather types and the amount of flood damage they are likely to cause becomes visible. The likelihood of flood damage and large flood events are found to substantially vary by weather type. The results of this study have broader and immediate impacts on real time weather forecasting and even climate change projections.