JWA Ensemble Precipitation Forecast
Services

We Support Weather Risk Management with JWA Ensemble Precipitation Forecast, which Predicts Multiple Weather Scenarios

“JWA Ensemble Precipitation Forecast” is an advanced service of Japan Weather Association that provides the ensemble precipitation forecasts^*1 with high-resolution of 5 km grid and hourly intervals of up to 15 days ahead.
Because this forecast predicts multiple scenarios, it is effective at conducting risk management that takes into account the range of uncertainty in the weather forecasts. JWA collects and revises the numerical forecasts issued by global weather organizations and then calculates the probability of heavy rain occurrence, the probability of exceeding the thresholds of heavy rain and the multiple scenario forecasts using ensemble prediction. This enables our customers to conduct planning and management that accounts for the risks of uncertainty in forecast models.
In addition, by utilizing our own correction process and AI technologies (such as deep learning) for spatiotemporal downscaling^*2, we provide high-resolution ensemble precipitation forecasts.

^{* 1} Ensemble forecasting: A method of using multiple initial conditions with slight variations, or perturbations, and producing multiple forecasts to predict the most likely phenomenon or worst-case scenario. It also allows estimation of the likelihood that the prediction will change and the degree to which it will change.

^{* 2} Downscaling: A method to present forecast data with higher temporal and spatial resolution. With this method, it is possible to present more localized, short-duration heavy rainfall forecast that does not appear in the original forecast.

Service Content

Features

• Provides high-resolution ensemble precipitation forecasts with 5 km grid and hourly intervals, up to 15 days in advance.
• Enables planning and management by utilizing ensemble forecasts, which take into account the risks of inaccurate forecasts.
• Spatiotemporal downscaling using AI technology (e.g., deep learning).

Applications

• Dam and river management
• Hydropower generation planning
• Predictions of flooding and landslides
• Decision making support about operation and management in the event of heavy rain and heavy snow (municipalities, road management, railway operation management, train vehicle evacuation support)
• Corporate Business Continuity Planning during severe weather forecast
• Decision making in the feasibility of outdoor events

Related news

Japan Weather Association starts the operation of “Decision Making Support Service for Reservoir Discharge” – Introduced at two dams in Chiba Prefecture; Started patent application for AI-based precipitation forecasting method – (July 3, 2020 Japan Weather Association announcement)
https://www.jwa.or.jp/news/2020/07/10357/

Japan Weather Association launches “Decision Making Support Service for Reservoir Discharge” – Aiming to reduce flood damage by providing “high resolution” and “high accuracy” forecasts of up to 15 days in advance. – (March 6, 2020 Japan Weather Association announcement) https://www.jwa.or.jp/news/2020/03/9451/