This text is part of the Weather Preparedness & Resilience Toolbox developed by the YOUROPE Event Safety (YES) Group within YOUROPE’s 3F project (Future-Fit Festivals). It is aimed at everyone involved in planning, building, and operating open-air events. It helps festivals and other outdoor events become truly weather-ready by offering both practical and research-based resources as well as background information on weather and climate. Learn how to design safer and more weather-resilient outdoor events.

WMO EARLY WARNING SYSTEM: IMPLEMENTATION & CHECKLIST

Overview: What the WMO (World Meteorological Organization) Early Warning System Is

The WMO defines an Early Warning System (EWS) as an integrated framework that anticipates and communicates weather-, climate- and water-related hazards in time for people and organisations to take action. WMO’s model consists of four core components:

1. Disaster risk knowledge (hazard and vulnerability assessment),
2. Detection, monitoring, analysis, and forecasting,
3. Warning dissemination and communication, and
4. Preparedness and response capabilities.

WMO and partners through the Early Warnings for All (EW4All) initiative emphasize end-to-end, people-centred, multi-hazard systems that ensure warnings are actionable and reach vulnerable populations with sufficient lead time.

Applying WMO Early Warning Principles to Open-Air Festivals

For open-air festivals, especially multi-day or large-attendance events, integrating EWS principles enhances safety by anticipating weather-related risks and enabling timely protective actions.

1 Disaster Risk Knowledge: Event-Specific Hazard & Vulnerability Assessment

Actionable Steps

• Conduct a hazard profile for the festival venue (e.g., thunderstorms, heatwaves, strong winds, heavy rain, lightning) using historical climate data and forecasts.
• Assess vulnerabilities specific to festivals, for example:
  • Large congregations with limited shelter,
  • Stages, tents, and structures susceptible to high winds,
  • Heat stress risk for crew and audiences,
  • Waterlogging and flash-flooding in low-lying grounds.

2  Detection, Monitoring & Forecasting: Tailored Weather Surveillance

Actionable Steps

• Establish real-time weather monitoring for the festival region by subscribing to or integrating:
  • National Meteorological and Hydrological Service forecasts,
  • App-based meteorological alerts,
  • On-site sensors (anemometers, rain gauges),
  • Lightning detection and heat index monitoring,
  • Meteorological experts on site
• Define thresholds/triggers (e.g., wind > X km/h, lightning within Y km) that automatically prompt protective actions.

Process Integration

• Assign roles for monitoring during critical phases (build-up, peak attendance, break periods).
• Use recognised forecasting products that are consistent with WMO-standard services (such as outputs from the WMO Integrated Processing and Prediction System).

Benefits

• Provides operational teams with continuous situational awareness.
• Ensures early detection of rapid onset risks (e.g., sudden thunderstorms).

3 Warning Dissemination & Communication: Multi-Channel Real-Time Alerts

Actionable Steps

• Establish a warning dissemination plan tailored to festival stakeholders:
  • Internal communication (operations desk, security, first aid),
  • Front-line staff and volunteers,
  • Audience (PA systems, mobile alerts, app notifications, social media).
• Standardize messaging using clear, concise alert levels (e.g., Watch, Warning, Evacuate) tied to pre-defined thresholds.
• Integrate messaging protocols with WMO’s Common Alerting Protocol (CAP) where possible, to ensure consistent, interoperable alerts.

Best Practices

• Use redundant channels. Make sure that everyone including for example people being blind or deaf are having the chance to get all necessary information.
• Ensure messages are actionable (e.g., “Proceed to shelters within 10 minutes”).

Benefits

• Maximizes reach and comprehension across diverse audiences.
• Avoids confusion during high-stress moments.

4  Preparedness and Response Capabilities: Operational Readiness & Action Plans

Actionable Steps

• Train staff and volunteers on:
  • Warning interpretation,
  • Protective actions (e.g., sheltering, evacuation),
  • Incident escalation procedures.
• Prepare standard operating procedures (SOPs) for hazard triggers.
• Conduct tabletop exercises, drills, and rehearsals anchored on weather hazard scenarios — this reinforces readiness.

Benefits

• Enhances confidence and reduces reaction time.
• Ensures coordinated action between festival staff and emergency services.

Integration Into Broader Risk & Resilience Frameworks

To fully adopt WMO EWS principles, festivals should institutionalize weather and climate risk as part of their operational risk governance:

• Policy & Documentation
  • Embed EWS expectations in Safety Management Plans and Continuity Plans.
  • Align with local civil protection frameworks.
• Coordination with National/Local Services
  • Liaise with NMHS and emergency services for shared situational awareness.
  • Align alert thresholds and definitions.
• Continuous Improvement

1. Post-event review of weather impacts and systemic responses.
2. Update hazard thresholds and SOPs based on experience.

In essence, applying WMO EWS principles to festival planning transforms weather risk from a reactive concern to an anticipatory and actionable part of event operations — aligning with resilience, safety, and continuity best practices.

Example Use Cases in Festival Context

Weather Hazard	EWS Application	Festival Action
Severe thunderstorms / lightning	Continuous radar/sensor monitoring + threshold triggers	Suspend performance; advise shelter; secure equipment
Extreme heat / heatwave	Forecasting & heat index alerts	Activate hydration stations; shade areas; adjust activity schedules
Heavy rainfall / flash floods	Rainfall forecasts and ground sensors	Divert access routes; pre-emptively protect electrical infrastructure
High winds	Wind threshold monitoring	Lower temporary structures; restrict aerial effects

WMO EARLY WARNING SYSTEM: PRACTICAL CHECKLIST FOR OPEN-AIR FESTIVALS (adapt to your festival)

1. DISASTER RISK KNOWLEDGE

(Do we understand what can realistically happen at THIS site, at THIS time?)

Site-Specific Hazard Identification

☐ Relevant weather hazards identified (e.g. lightning, heavy rain, wind, heat, cold, fog)
☐ Seasonal and climatological risks assessed for event dates
☐ Rapid-onset hazards (thunderstorms, gust fronts) explicitly considered
☐ Secondary effects considered (ground saturation, structural loads, power failure)

Vulnerability & Exposure

☐ Audience size, density, and mobility assessed per weather scenario
☐ Vulnerable groups identified (children, elderly, intoxicated persons, staff in PPE)
☐ Temporary structures assessed for weather sensitivity (wind, rain load, anchoring)
☐ Site-specific weak points identified (slopes, bottlenecks, drainage, shade deficits)

Risk Documentation

☐ Weather hazards included in the formal event risk assessment
☐ Weather risks linked to concrete operational impacts (not generic descriptions)
☐ Thresholds and consequences documented (what happens if X is exceeded?)
☐ Responsibilities assigned and documented (who decides, who acts?)

2. MONITORING, DETECTION & FORECASTING

(Do we see hazards early enough to act?)

Forecasting & External Sources

☐ Reliable national meteorological service forecasts integrated
☐ Short-term and nowcasting products available (radar, lightning data)
☐ Warning levels and terminology understood by the operations team
☐ Clear understanding of forecast uncertainty and lead times

On-Site & Near-Site Monitoring

☐ Continuous weather monitoring assigned to a specific role
☐ On-site instruments available where relevant (wind, rain, temperature)
☐ Lightning detection or proximity alerts available for thunderstorm risk
☐ Monitoring continues during all critical phases (build-up, show, dispersal)

Trigger Thresholds

☐ Operational thresholds defined (e.g. wind speed, lightning radius, heat index)
☐ Thresholds linked to pre-agreed actions (not ad-hoc judgement only)
☐ Escalation logic defined (watch → warning → action)
☐ Thresholds validated against site and infrastructure characteristics

3. WARNING DISSEMINATION & COMMUNICATION

(If we know, can we tell the right people clearly and fast enough?)

Internal Communication

☐ Clear internal warning chain defined (monitor → decision → action)
☐ Control room / operations center receives real-time updates
☐ All key functions reachable at any time (production, security, medical)
☐ Backup communication channels available (radio, phone, runners)

External / Audience Communication

☐ Audience warning channels defined (PA, screens, app, social media)
☐ Messages pre-prepared for typical weather scenarios
☐ Language is simple, directive, and action-oriented
☐ Messages avoid technical meteorological jargon

Message Quality

☐ Warnings explain WHAT is happening, WHAT to do, and WHEN
☐ Time references are explicit (“within 10 minutes”, “immediately”)
☐ Messages are consistent across all channels
☐ Communication responsibility clearly assigned

4. PREPAREDNESS & RESPONSE CAPACITY

(When the warning comes, can we actually act?)

Procedures & Decision-Making

☐ Weather-related SOPs exist (pause show, evacuate, shelter, resume)
☐ Decision authority clearly defined (who can stop the show?)
☐ Interface to authorities and emergency services clarified
☐ Legal duty of care considered in decision logic

Staff Training & Awareness

☐ Key staff trained to interpret weather warnings
☐ Frontline staff briefed on expected actions and crowd guidance
☐ Volunteers know escalation paths and do not improvise messages
☐ Weather scenarios included in briefings and shift handovers

Exercises & Validation

☐ Table-top exercise or scenario walkthrough conducted
☐ Weather scenario tested under realistic time pressure
☐ Lessons learned documented and incorporated
☐ Roles and procedures adjusted after testing

5. REVIEW, LEARNING & CONTINUOUS IMPROVEMENT

(Do we get better every time?)

☐ Weather conditions and impacts logged during the event
☐ Near-misses and decision points documented
☐ Post-event review includes weather handling and communication
☐ Thresholds and SOPs updated based on experience
☐ Feedback shared with planners, production, and safety teams