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Météo-France's Weather Alert System
This article explains Météo-France's weather alert system, including its methodology, decision-making process, performance metrics, and collaboration with the French government.
French
France
HealthClimate ChangeFranceSafetyWeatherRiskForecastAlert
Météo-FranceFrench Government
Pierre Tabary
- How is an orange or red alert decided?
- Orange and red alerts are determined through a collaborative process involving meteorological engineers and considering local vulnerabilities. Objective thresholds are used, but these can be adjusted based on aggravating factors.
- What is Météo-France's vigilance system?
- Météo-France's vigilance system, created in 2001, uses a four-level color-coded alert system (green, yellow, orange, red) to warn the public and authorities about weather risks.
- How does Météo-France build its weather forecasts?
- The system relies on weather forecasts, using various observation tools like weather balloons, radars, and satellites to predict future atmospheric states. Multiple forecast scenarios are created to account for uncertainties.
- What are the performance goals of Météo-France's system?
- The system aims for a low rate of missed alerts (around 2%) while keeping false alarms under 16%. Adjusting these percentages involves a trade-off, as over-alerting could reduce public vigilance.
- How does Météo-France collaborate with the French government?
- Météo-France works closely with the French government to set alert thresholds and communicate effectively. Continuous communication ensures that authorities have the information they need to take preventive measures.