Funnel Clouds Vs. Wall Clouds Funnel Clouds, Wall Clouds & Scud Clouds Funnel Cloud • Funnel Clouds rotate, usually rapidly, extending downward from the cloud base
• Look for debris/dirt being kicked up to ascertain if the Funnel Cloud has reached the ground and become a tornado
• As opposed to scud clouds, funnel clouds typically have a smooth appearance
• Funnel clouds are generally located near the up- Severe Weather draft, usually vertical, and several orders of magni- tude smaller than parent wall cloud. Spotter Safety • Tail Clouds are often horizontal and funnel-like Wall Cloud but do not rotate. Guide • Tail Clouds should not be confused with actual funnel clouds • Scud clouds will have a ragged non-funnel appear- ance • Scud clouds will move up and down from the cloud base • Most important distinction with all of the could types is ROTATION!!!!
• If the cloud is not rotating there is no tornado!!! Scud Clouds
Story County Emergency Management
Lori Morrissey, Coordinator Saving Lives 900 6th St & Nevada, IA Protecting Property 50201
Phone: 515.382.7315 Fax: 515.382.3349 Lori Morrissey Coordinator E-mail: [email protected] 515.382.7315 www.storycounty.com/emergencymanagement www.storycounty.com/emergencymanagement
Severe Storm Spotter Safety Guide
General Spotter Safety Lightning Hazards Communication with Dispatch
• Set up Command Post at the fire station • Pay attention to approaching areas of lightning Please be patient. There is a large increase in ra- dio & phone traffic during a severe weather • Stay in your vehicle if possible • Always storm spot in teams of two event. Here are a few tips for communicating • Stay away from wire fences; they carry lightning with Dispatch. • One spotter can watch the storm while the currents to you other watches the road and for other hazards • • Do not lean on vehicle and act as a path to the Do not use Tac Channels. These need to be free for emergencies arising from the storm • Try to watch the storm from the southwest ground looking north • Avoid single trees and being highest object • Do use your private channels for talking be- tween personnel • Make sure you have escape routes from your • If you hair stands up there is potential for a light- ning strike spotting location • Continue to monitor the main Fire/EMS • Get in your vehicle or squat on the ground on the channel for updates from Dispatch • Do not park under or around power lines balls of your feet What to report to Dispatch • Make sure you are well off the travel portion of the road with hazards/flashers on • Hail needs to be reported as nickel, dime, • Stay in your vehicle if possible golf ball or baseball. Do Not report marble Wind Speed Estimation Chart size hail. Marbles come in different sizes • If you do leave your vehicle do not get to far • 25-31 mph Large branches in motion away • High Winds & Building Damage • 32-38 mph Whole trees in motion Night Time Spotting • Downed power lines & trees. Estimate the • 39-54 mph Twigs break off diameter of the tree. Advise if power lines or If there is a need for night time spotting here are trees are blocking the road. • 55-72 mph Damage to chimneys & TV additional tips to ensure your safety. antennas, large branches broken & some • Damage to buildings • Note the wind direction & sudden changes trees uprooted • Funnel clouds, Wall Clouds, and Tornadoes. in direction • 73-112 mph Removes shingles, windows Advise direction of travel & speed. • Watch for ground based flashes produced by broken, trailer houses overturned, trees • Flash Flooding a tornado hitting power lines uprooted
• Use lighting to note storm structure & possi- • 113+ mph Roofs torn off, weal buildings ble lowering cloud base & trailer houses destroyed, large trees up- rooted