Modelling extreme rainfall events: storm scale Unified Model (UM)

A project to assess and optimise the ability of the next generation Numerical Weather Prediction (NWP) model to predict extreme rainfall events.

Documents

Modelling extreme rainfall events - final report (643 KB) PDF

Modelling extreme rainfall events - technical summary (45 KB) PDF

Modelling extreme rainfall events - technical report (6 KB) PDF

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Details

Objectives

This project investigates the Unified Model (UM) rainfall prediction method. This is a storm scale configuration of the Met Office Numerical Weather Prediction (NWP) model, which predicts extreme rainfall events up to 18-24 hours before the event. This project aims to assess the ability of this model to predict extreme rainfall events. This includes determining what it is about the meteorology of these events that must be captured by the model in order to produce useful predictions.

Approach

This report makes recommendations that’ll be used to inform future research and development projects and strategies. It also describes the relationship between this project and other work in the same area within the UK and Europe.

This research has:

  • progressed the body of scientific knowledge about the nature of extreme rainfall events in the UK
  • improved the ability of current state of the art NWP models to forecast extreme weather events
  • developed new approaches for presenting and assessing the forecast output

Outcome

The results of this research were included in the 2008 Pitt Review. This reviewed flood policy in the UK following the widespread flooding in England during June and July 2007.

This project ran from November 2005 to February 2007 at a cost of £183,962.

Published 18 February 2021