ML4WX

Post-processing & calibration

Deep Learning for Improving Numerical Weather Prediction of Rainfall Extremes

Philipp Hess, Niklas Boers

Journal of Advances in Modeling Earth Systems · · Potsdam Institute for Climate Impact Research (PIK), Technical University of Munich (TUM)

PaperPDF

In one sentence. Deep networks trained on an NWP ensemble with a frequency-weighted loss correct rainfall, improving extreme-event forecast skill by factors of two to above six.

Abstract

The accurate prediction of rainfall, and in particular rainfall extremes, remains challenging for numerical weather prediction models. This can be attributed to subgrid-scale parameterizations of processes that play a crucial role in the multi-scale dynamics, as well as the strongly intermittent nature and the highly skewed, non-Gaussian distribution of rainfall. Here we show that a specific type of deep neural networks can learn rainfall extremes from a numerical weather prediction ensemble. A frequency-based weighting of the loss function is proposed to enable the learning of extreme values in the distributions' tails. We apply our framework in a post-processing step to correct for errors in the model-predicted rainfall. Our method yields a much more accurate representation of relative rainfall frequencies and improves the forecast skill of extremes by factors ranging from two to above six, depending on the event magnitude.

Labels

Topic
Post-processing & calibration, Extremes & hazards
Type
New model or method
Method
CNN / U-Net
Time scale
6 h–3 days
Domain
Regional
Data
NWP analysis or forecasts (IFS, GFS, ...)
Status
Research
Identifiers
DOI:10.1002/essoar.10507827.1 OpenAlex:W3196443665
Added
2026-10-22

Labels and summary are generated by Claude and reviewed weekly. Wrong? Edit this entry.