How the preparedness score works
The calculator combines alert type, time until arrival, wind, hail, lightning distance and your current situation. A warning, nearby lightning, large hail, severe wind or outdoor exposure raises the preparedness level.
What counts as severe?
In the United States, severe thunderstorm criteria commonly include damaging wind, large hail or tornado potential. This page simplifies those thresholds for household planning and does not replace official weather warnings.
Checklist before storms arrive
- Move indoors and away from windows.
- Secure loose outdoor objects if it is safe and time allows.
- Charge phones and keep flashlights nearby.
- Avoid driving into flooded roads or areas with falling limbs.
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FAQ
Is this a weather forecast?
No. It is a preparedness planning tool. Use official local forecasts, warnings and emergency alerts for real-time decisions.
How do I estimate lightning distance?
A rough rule is seconds between flash and thunder divided by five to estimate miles.
Should I drive during a severe thunderstorm warning?
Avoid nonessential driving during dangerous wind, hail, flooding or low visibility conditions.