What is a PDS Tornado Warning
A Particularly Dangerous Situation tornado warning is issued by the National Weather Service when a confirmed large and violent tornado is occurring or about to occur. This warning indicates that the tornado poses an exceptional threat to life and property due to its strength, size, or other dangerous characteristics. PDS warnings are reserved only for the most severe tornado situations and are not issued frequently.
Key Differences from Standard Tornado Warnings
A standard tornado warning indicates that a tornado has been sighted by weather spotters or detected by Doppler radar and poses a threat to a specific area. However, a PDS tornado warning goes further by emphasizing that this is an exceptionally dangerous and violent tornado with particularly high potential for major damage and loss of life. The PDS designation alerts the public that this is not an ordinary tornado warning and demands the most urgent protective action possible.
When PDS Warnings are Issued
PDS tornado warnings are issued when meteorologists confirm that a tornado displays characteristics indicating it will cause particularly severe damage. These characteristics may include a very large visible tornado, strong rotation, rapid movement, or radar signatures showing extremely intense winds. Weather services use specific criteria based on damage potential and observed or indicated wind speeds to determine when a PDS designation is appropriate.
Recommended Actions During a PDS Warning
People in the path of a PDS tornado should immediately move to the lowest level of a sturdy building, preferably a basement or an interior room without windows such as a bathroom or closet. This is more critical than during a standard tornado warning because PDS tornadoes are more likely to cause structural failure and injuries. People should not attempt to outrun the tornado and should protect themselves from flying debris by covering their heads and bodies.
Frequency and Historical Context
PDS tornado warnings are uncommon, issued only a handful of times each year across the United States. They represent the most severe storms that meteorologists can identify in real-time. Understanding the difference between standard and PDS warnings helps the public recognize when a situation demands the most serious and immediate protective response. 
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