What to Report

Things Spotters Report

• Tornadoes - Tornadoes, funnel clouds
• Hail - 1/2" in diameter or larger
• Thunderstorm Wind Gusts - Estimated 50 mph or greater
• Dense Fog - Visibility of 1/4 mile or less
• Flooding or heavy rain - Any flooding that covers roads or threatens property. Rainfall rates of one inch per hour or heavier.

Ever wonder how spotters are able to estimate wind speed or hail size? Below are the classifications.

Estimating Wind Speed

• 25-31 mph - Large branches in motion; whistling heard in telephone wire
• 32-38 mph - Whole trees in motion; inconvenience felt walking against the wind
• 39-54 mph - Twigs break off trees; wind generally impedes progress
• 55-72 mph - Damage to chimneys and TV attenas; pushes over shallow rooted trees
• 73-112 mph - Peels surface off roofs; windows broken; light mobile homes pushed over; moving cars pushed off road
• 113-157 mph - Roofs torn off houses; cars lifted off ground

Estimating Hail Size

• 1/4" - pea
• 1/2" - marble
• 3/4" - dime
• 7/8" - nickel
• 1" - quarter
• 1 1/4" - half dollar
• 1 1/2" - walnut or Ping Pong ball
• 1 3/4" - golf ball
• 2" - hen egg
• 2 1/2" - tennis ball
• 2 3/4" - baseball
• 3" - teacup
• 4" - grapefruit

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