The NOAA Precipitation Prediction Grand Challenge: Advancing Predictions of Extreme Rainfall

The impacts from extreme precipitation are deadly, damaging, and increasing in a warming climate. For example, in just the past year extreme rainfall events have caused billions of dollars in damages and hundreds of fatalities in the US. Unfortunately, NOAA models (global models in particular) have seen marginal improvement in precipitation skill (~15%) over the past 2 decades. Further, partner needs in terms of accuracy, specificity, and lead time often exceed current capabilities. In response, NOAA has developed a strategy for a decadal effort to improve forecast precipitation (from mesoscale weather to seasonal timescales) - called the NOAA Precipitation Prediction Grand Challenge.

The goal of this effort is to dramatically improve precipitation forecasts in terms of accuracy, extent in time, and reliability. The challenge demands investment across the value chain from basic understanding of precipitation processes and predictability limits, to enhanced observations, data assimilation, improved models, post-processing and tools for the human forecaster, culminating in understandable, actionable, and equitable services -- these services being informed by stakeholder engagement. Thus, it is a grand Research-to-Operations challenge.

This initiative and early results will be described, with attention focused on opportunities for community involvement in R2O.