Convective Sigmet (WST)

A Convective Sigmet may be issued for any of the following;

1. Severe thunderstorms due to:
   • surface winds 50 knots or greater.
   • hail at the surface greater than or equal to 3/4 inches in diameter.
     
   • tornadoes.
     
2. Embedded thunderstorms.
3. A line of thunderstorms.
4. Thunderstorms greater than or equal to VIP level 4 affecting 40% or more of an area of at least 3,000 square miles.