| Contents |
| Overview |
| Storm Spotter Reporting Procedures |
| Storm Spotting And Storm Chasing |
First off, thanks to Tim Vasquez, Chuck Doswell, and others for this data. DS
The 1996 movie ''Twister'', made storm chasing appear to be an exciting adventure. However, there are major differences between the movie and real life. Other excellent Storm Chasing information links include Storm Track Magazine/Storm Chaser Homepage, Tempest Tours Storm Chasing Expeditions, and The Storm Chasing Network.
Normally, March, April, and May are thought of as peak tornado seasons; but there have been tornado outbreaks in October, November, and December, as well as at other times of the year. Tornadoes have occurred in all 50 states, and at all hours of the day and night.
* Law enforcement and Civil Defense spotters -- report to the National Weather Service via NAWAS, radio, or other direct communications links as described by your Emergency Operations plan.
* When the telephone is your only communications method, call your primary or alternate contact, and ask them to relay your report to the National Weather Service. If you're unable to reach the primary or alternate contact, place an EMERGENCY CALL through the telephone operator to the National Weather Service. If the call is long distance, it can be made COLLECT. Report promptly, as the storm may interrupt communications.
WHERE you saw it: the directon and distance from a known location (for example, 3 miles south of Beltsville).
WHEN you saw it: make sure you note the time of your observation.
WHAT it was doing: describe the storm's direction and speed of travel, size and intensity, and destructiveness. Include any amount of uncertainty as needed; i.e. ''funnel cloud, no debris visible at the surface, but too far away to be certain it is not on the ground''.
IDENTIFY yourself and your location. Give your spotter code number if one has been assigned. If you are an amateur radio operator, give your callsign, as per FCC Rules.
2) Hail, 1/4 inch or larger. Approximate sizes in diameter are Pea (1/4 inch), Marble (1/2 inch), Penny (3/4 inch...storms classed as severe at this or above), Quarter (1 inch (the 25 cent piece, NOT 1/4 inch)), make sure your report clarifies this fact), Golfball (1 3/4 inches), Baseball 2/3/4 inches), or larger.
3) Damaging winds, usually 50 mph or greater. Adapted from the Beaufort and Fujita Wind Scales, here's a way to estimate wind speeds in mph with severe storms:
25-31 Large branches in motion, whistling heard in telephone wires.
32-38 Whole trees in motion; inconvenience felt walking against wind.
39-54 Tropical Storm force winds. Twigs break off trees; wind generally impedes progress.
55-72 Damage to chimneys and TV antennas; pushes over shallow rooted trees.
73-112 Hurricane Force winds. Peels surface off roofs, windows broken, light trailer houses pushed or overturned, moving automobiles pushed off roads.
113-157 Roofs torn off houses, weak buildings and trailer houses destroyed; large trees snapped and uprooted.
158 or more Severe damage, cars lifted off ground.
4) Flash Flooding
5) Heavy Rain at the rate of 1 inch or more an hour
* At night, lightning flashes can aid in identifying the Rain Free Base, Wall Cloud, and Precipitation Area. Although a loud roar is frequently associated with tornadoes, strong straight line winds can also produce such a sound.
* If you spot from a fixed location, use a map to determine distance and direction to known landmarks, such as water towers, TV towers, etc. This will help you eliminate distance and direction in your reports. Mobile spotters should always have up-to-date maps, and be familiar with the area in which they are operating.
* When available, use binoculars to look for rotation, and other cloud features. Once you spot a tornado, funnel cloud, or wall cloud, be alert for the formation of others in the area.
* If you find yourself in large hail, remember you are in or near the area where tornado formation is most likely in a tornadic thunderstorm.
* Always follow the basic safety rules. In open country, a spotter may be able to use his knowledge of the tornado's motion and available escape routes to drive away from the tornado safely. In urban areas, this is usually not possible because of traffic congestion. Make sure your family knows what to do in tornado emergencies, as you may not be available to direct or assist them.
1) A STORM SPOTTER visually observes weather as part of a local civil defense radio network...a STORM CHASER observes weather for personal or business reasons.
2) A STORM SPOTTER usually has an amateur radio handheld transceiver (HT)...a STORM CHASER may or may not have radio gear.
3) A STORM SPOTTER rarely leaves the county to spot...a STORM CHASER travels hundreds of miles.
4) STORM CHASING IS EXTREMELY DANGEROUS, AND NOT FOR AMATEURS. Those who have been chasing have done it for years...knowing what to look for, and escape routes. Chasers will NOT intentionally put themselves in harms way. Storms can move as fast as 90 miles per hour, and can be quite fickle in their movements...changing direction before you realize it. If the tornado you're observing doesn't seem to be moving, but is getting larger...chances are it's heading right for you!!
5) Chasers travel in groups...it is foolhardy (and stupid) to travel alone, or without another experienced chaser. You will NOT become a chaser overnight...it takes several years to become an experienced, mature chaser. It's advised to NOT have your children/kids with you...in a severe weather situation, you need as little distraction as possible...to keep your wits about yourself, should you need to get out of the danger area quickly.
6) Many chasers analyze the weather conditions in detail before a chase, so they know what to expect. Much of chasing is actually a ''waiting game''...waiting for the storms to develop. You will NOT see a tornado every day, after every meal, etc. Many days you'll see NOTHING at all!! It's best to be knowledgeable about severe weather...much of this can be obtained through a SKYWARN Storm Spotter course, conducted by local National Weather Service offices...but this alone does NOT qualify you as a chaser...just as a spotter. If you obtain data from a National Weather Service office...remember that you are A GUEST there...keep your opinions of their forecasts TO YOURSELF...and DO NOT touch their equipment without permission...have them look the data up for you, if they have the time to do so. Irresponsible chasers have caused many National Weather Service offices to take a dim view of chasers as a whole.
7) Chasers have a wide range of communications equipment, to stay in touch with emergency services personnel, and the National Weather Service and each other. If you don't know how to use the equipment, or are not authorized to (such as Ham Radio, where an FCC license is required), do NOT use it!!
8) Chasers, for the most part, are responsible. These will not drive at breakneck speed to try to intercept a storm. Road conditions and traffic laws must be dealt with. There's always another day to chase. Also, be aware of the small towns that ''roll up the sidewalks'' at dusk. Also, be aware of your surroundings...isolated areas can be prime territory for snakes; as well as roaming livestock...hitting cattle can severely damage your vehicle. Have a First Aid kit in case of an emergency.
9) If you find yourself in an area with large hail, you are in or near an area where tornado development is likely to occur. Be sure you have an escape plan to get out of there fast!! Besides the tornadoes and hail, lightning, strong wind, and heavy rain, which can lead to hydroplaning, are all dangers of severe weather; be alert for rapidly changing weather conditions, and be prepared to get out of danger on a moments notice. Large hail can also destroy your vehicles windows and windshields.
10) Do not try to drive and videotape storms at the same time...driving is more important!! It's best to have a partner to videotape, or to let you know which route to take. That chase partner will also need to have a lot in common with you, as it'll be like ''a spouse''. You may drive over 1000 miles in a day...and at the end of the day, you'll need to find lodging.
11) Take care of yourself with your eating, sleeping, and other personal hygiene habits. Also, do not sacrifice your family, your job, or your studies, just to chase storms. This is purely irresponsible. Also, be aware that, with few exceptions, storm chasers DO NOT GET PAID for their work.
12) Make sure your chase vehicle is well maintained. Watching a severe storm rapidly approach you is NOT the time to discover that your battery just ''bought the farm'', or realize that you have a flat tire, etc. Be sure you're able to get fuel, etc. for your vehicle especially after dark...many small towns, as noted above, close many of their businesses at dusk.
13) Do NOT try to drive right into the center of the storm (core punching). If you find yourself surrounded by wrapping rain bands, you're in extreme danger, as the tornado could come on you without warning. This is especially true at night, when all the dangers of severe storms are hidden. The most violent area of the storm is known as the ''bear cage''. On a good day, you can eat the bear...but on a bad day, the bear can have you for supper!!
14) Remember that severe weather affects not just open areas...many homes, businesses, and lives, are damaged or destroyed when storms hit where people live and work. Be aware that someone could be dying in that tornado that you're watching.