Severe Weather Reporting Criteria

Note: This is copied directly from the NWS Basic Storm Spotters guide.

Many types of weather information are needed from storm spotters; however, some types of information are much more important than others and some need not be offered.  Strict adherence to the reporting criteria allows vital information to be communicated as soon as possible.  Also, some of the reporting criteria should receive higher priority communication than others as indicated below.

Urgent Priority

1. Tornado

2. Funnel cloud

3. Rotating wall cloud

4. Flash flooding

High Priority

1. Hail 1-inch diameter or larger

2. Wind speed greater than 58 mph

3. Persistent non-rotating wall cloud

4. Rainfall 1 inch or more per hour

Lower Priority

1. Hail 1/2-inch diameter or larger

2. Wind speed greater than 40 mph

3. Cloud features suggesting storm organization

4. Other locally-defined criteria

NOTE: When reporting 1/2-inch diameter hail, do not use the term �marble� since marbles can come in a variety of sizes.  If you have a lowering, watch if for 10 minutes before placing a report.  Net control has the authority to modify the reporting criteria as needs dictate.  This can be either the addition of or reduction in restrictions.

1.

Clear Sky reports

2.

Rain fall (in general)

3.

Level of lightning activity

1.

Reports of weather you have heard from the media, law enforcement or other "3^rd parties."  These types of reports are not always from trained spotters.  Repeating media reports (on the air) is redundant at best. 

2.

All three of these can prevent emergency traffic from being passed to the appropriate people in a timely manner.  The result is only to squander net resources.  

Activity that is not appropriate for a Net:

If the net is extremely busy, do not check in for checking-ins sake.  This creates unneeded traffic and can impede the (timely) flow of relevant information.  Monitor activity and check in when you have traffic.

Troubleshooting of technical problems.  If you know you are having issues with your equipment or are advised of it, take your station "off net" and troubleshoot the problem.

Announcements of non-event related activity.

Asking if a Net is in progress.  If in doubt, exercise the "release to listen" method.  Listen for either Net control to state a net is in progress or for the repeater to announce it ("wx" system reset).

Deviating from established reporting criteria.  Clear sky, typical rainfall, lightning and light winds reports are NOT wanted.

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