Workshop: Warm Conveyor Belts – a challenge to forecasting

ECMWF | Reading | 10-12 March 2020

Warm Conveyor Belts (WCBs) are cloudy regions of ascent and strong diabatic forcing along the cold front of a synoptic depression. They can lead to heavy local precipitation and can have downstream impacts such as the onset and maintenance of blocking. They are therefore important in both weather and climate prediction. However, WCBs are also associated with inherently increased error growth-rates, and are difficult to constrain in analyses - due partly to clouds having a strong non-linear impact on satellite observations and moist processes leading to larger model errors. Indeed, forecast “busts” are often associated with the existence of WCBs. In the climate text, model deficiencies in WCBs and in their large-scale drivers are likely to be particularly relevant; with implications for the future statistics of precipitation, heatwaves and droughts for example. This workshop will bring together observation, assimilation, model, forecast and research communities to explore these aspects.  The aim is to improve understanding and to help develop optimal strategies to improve weather and climate prediction - a goal which would be very difficult for a single such community to achieve on its own. The workshop will include invited and submitted talks, and will have a strong focus on posters.