You are at: NWS Norman » Storm Spotter Resource Center » Special Topics

Send a

Special Topics for Storm Spotters

National Severe Weather Workshop

Storm spotters, emergency managers and anyone else interested in severe weather are invited to attend the National Severe Weather Workshop, to be held March 4-6, 2010 at the Embassy Suites Hotel and Conference Center in Norman, Oklahoma. The three-day workshop will feature a variety of speakers presenting topics that should be of interest to storm spotters and anyone interested in weather. The workshop will conclude with free storm spotter training at 1 pm on Saturday, March 6, 2010. For complete details and registration information, visit

Storm-Based Warnings

National Weather Service Storm-Based Warning Webpage
As of October 1, 2007, the National Weather Service began issuing storm-based warnings for severe thunderstorm, tornado and flood hazards. Prior to that, warnings were issued based on geographical boundaries. The storm-based warning technique increases the specificity and accuracy of warnings that are issued now. When severe weather impacts Oklahoma now, you can go the the NWS Norman homepage and instead of entire counties being shaded in for warnings, only the section of the county under a warning will be shaded. For more on storm-based warnings, click on the link above.

Enhanced Fujita Scale

Storm Prediction Center EF-Scale Webpage
Warning Decision Training Branch EF-Scale Webpage
EF-Scale Report (PDF)
As of February 1, 2007, the National Weather Service began rating tornadoes on the "Enhanced Fujita Scale". This scale allows damage surveyors to be more precise and accurate when rating tornado damage. The scale utilizes 28 different "damage indicators" (basically objects or buildings that are commonly damaged by tornadoes) with varying "degrees of damage" and expected wind speeds for each damage indicator. For more information on everything related to the EF-Scale, visit the links above. It is important to note that while tornadoes are now being rated on the EF-Scale, the historical database with tornadoes being rated on the F-Scale has been preserved.

Current Research Projects in Meteorology

NSSL Polarimetric Radar Webpage
NSSL Phased Array Radar Webpage
NSSL Lightning Mapping Array Webpage
Currently, the National Severe Storms Laboratory is undertaking some exciting research here in Oklahoma that could have a major impact in the upcoming years on warnings, warning lead times, forecast accuracy, and so forth - all of which will benefit the public. For more information on these research projects, click on the links above.


There is a new, ongoing research project to help us understand more about tornadoes. VORTEX-2 (Verification of the Origins of Rotation in Tornadoes Experiment) has its first year of operations in 2009, and is set to resume in late April of 2010. This follow-on project to the VORTEX project of the mid 1990's is designed to study the genesis of tornadoes: how, when, and why they form; why some thunderstorms produce them and others do not; the structure of tornadoes, and the relationship of tornadic winds to damage; and how to better forecast tornadoes. For more information about the project, visit is the U.S. government's official web portal to all federal, state and local government web resources and services.