Tornado Risk Calculator
Calculate the Significant Tornado Parameter (STP) and Supercell Composite Parameter from CAPE, wind shear, storm-relative helicity, and LCL height.
Inputs
Results
Significant Tornado Parameter
1.83
Tornado Risk Level
Moderate — Significant tornadoes possible
How to Use This Calculator
- Enter CAPE (J/kg) from a sounding or model — higher values indicate greater instability.
- Set 0-6 km Bulk Shear (knots) — the vector wind difference between surface and 6 km altitude.
- Enter Storm-Relative Helicity (m²/s²) and LCL Height (m) from sounding data.
- Review Significant Tornado Parameter (STP): values above 1 indicate elevated tornado risk.
- Check Tornado Risk Level, Potential EF Scale, and Supercell Potential for complete storm hazard assessment.
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