Maximum Wind-Hail Size Tag To Be Appended To Severe Thunderstorm Warnings

Maximum Wind-Hail Size Tag To Be Appended To Severe Thunderstorm Warnings
Beginning March 1 2010, all NWS Central Region Weather Forecast Offices will be appending a tag line to severe thunderstorm warnings (CHISVRLOT), and follow-up severe weather statements (CHISVSLOT). For the Great Lakes, this tag line will also be appended to special marine warnings (CHISMWLOT).
The tag line is a concise code which identifies maximum hail size and wind speed expected for a given warning. Inclusion of this information at the end of these products represents an effort to respond to partner requests from the emergency management community as well as several societal impact groups.
For instance, one specific application concerns the activation of emergency alert sirens. Local area sirens are typically alarmed for tornadoes only. Decoding this tag line will facilitate the capability for local area emergency managers to activate sirens for particularly dangerous severe thunderstorm events when conditions exceed user defined thresholds, say for winds greater than 80 mph as an example. 
The maximum wind-hail size tag line is an experiment which will be evaluated from March 1 2010 through October 1 2010. During this period, we encourage comments or suggestions for improvement using the electronic survey provided at the link below. Your feedback will help us determine product usefulness, whether modifications are needed, and whether this will become a permanent addition to our warning format.
On-line customer feedback survey:
A service description document for this experiment is available on-line at:
A map showing affected offices is on-line at:
Additional questions or comments may be directed to:

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