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Advanced spotter guide Cover Photo - Alan Moller CI INTRODUCTION The Spotter ? s Role The National Weather Service NWS has a number of devices for detecting severe thunderstorms Included in these are radar satellite and lightning detection networks Howeve

Cover Photo - Alan Moller CI INTRODUCTION The Spotter ? s Role The National Weather Service NWS has a number of devices for detecting severe thunderstorms Included in these are radar satellite and lightning detection networks However the most important tool for observing thunderstorms is the trained eye of the storm spotter While radar is used quite often in severe storm warnings conventional weather radar will only indicate areas and intensities of precipitation It does not give any indication of cloud formations or wind ?elds associated with a storm Doppler radar which is being introduced across the country will give some indication of air motions inside a storm Doppler radar though will not give these indications down to ground level It is impossible for any radar to detect every severe weather event in its coverage area and radar occasionally suggests severe weather when in fact none is present Satellite and lightning detection networks provide general thunderstorm locations and are extremely valuable in data-sparse regions such as over mountainous terrain or over bodies of water They help to identify persistent thunderstorm areas and can be of aid in ash ood forecasting These systems provide little in the way of quantitative real-time information though and are not especially helpful during times of fast- breaking severe weather As a trained spotter you perform an invaluable service for the NWS Your real-time observations of tornadoes hail wind and signi ?cant cloud formations provide a truly reliable information base for severe weather detection and veri ?cation By providing observations you are assisting NWS sta ? members in their warning decisions and enabling the NWS to ful ?ll its mission of protecting life and property You are helping to provide the citizens of your community with potentially life-saving information Objectives of this Handbook During the past several years researchers have uncovered a tremendous amount of information regarding severe thunderstorm structure and behavior New theories regarding thunderstorm formation and tornado development have been presented Stormintercept teams have correlated these theories with observed visual features Our current understanding of the thunderstorm is markedly more complete than it was just ten years ago With this handbook and the Advanced Spotter Training Slide Set which was released a few years ago the time has come to pass this new understanding on to you the spotter Only by providing fresh training material can the NWS expect to maintain what has become a very important group of observers Prerequisites for Using this Guide The information contained in this guide is not for the novice spotter It is recommended that spotters go through two or more basic spotter training sessions and have some experience at actual storm spotting before attempting the intermediate advanced training material Spotters should be comfortable with the basic concepts of storm structure and storm spotting Obviously spotters should have a desire to learn the latest concepts of tornado and severe thunderstorm behavior II REPORTING PROCEDURES Primary and Secondary Contacts It is essential that any spotter network have a clear