If there is a high level of urgency associated with the protective action instruction, you may consider using one of the non-weather emergency message products in the Instruction Specific Warnings category. This focuses more attention on the desired public action than on the specific hazard, although the reason for the action should be given.
General Guidance
Use an Instruction Specific Warning when you wish to provide more extensively detailed public protective action instructions.
For example, consider a scenario where you need to combine evacuation instructions for part of the public within a given radius of an event, and shelter in place instructions for other portions of the public outside the evacuation perimeter. Instead of issuing two separate warnings, which could lead to confusion, use the Evacuation Immediate message as representing the higher level of urgency, but include additional shelter in place instructions in the same warning.
- You may use the Evacuation Immediate warning in relation to a weather event.
- Although you may issue an Evacuation Immediate warning in connection with a weather event such as a flood or hurricane, consider coordinating with your local Warning Coordination Meteorologist to have your instructions incorporated within the weather warnings or local statements being issued by the NWS as an alternative.
- You may use the Shelter in Place Warning for purposes beyond hazardous materials events.
- Shelter in place as a public protective strategy is usually thought of in the context of a hazardous materials event. It is also suitable for a radiological event. However, with modifications, it may also be suitable for a law enforcement type event. Instructions regarding ventilation systems would be omitted, and additional lockdown type instructions provided.
- The Shelter in Place Warning is more effective when the public has been educated in advance as to the meaning of the warning.
Instruction Specific Warnings
The following are general descriptions of the two NWEMs available in the Instruction Specific Warning category:
The following are general descriptions of the two NWEMs available in the Instruction Specific Warning category:
- Evacuation Immediate (EVI)
Description: A warning where immediate evacuation is recommended or ordered according to state law or local ordinance.
- This product is more appropriately used for shorter-fused events, i.e., those likely to occur within hours. For longer lead times, (such as tropical cyclones anticipated to impact a coastal area within days vs. hours), other methods may be more appropriate for communicating longer term evacuation instructions. Saving the Evacuation Immediate warning for near the end of an available evacuation window may preserve its impact, thereby enhancing compliance among those remaining behind.
- This product would be appropriate for weather related events such as imminent dam or levee failure.
- Shelter in Place Warning (SPW)
Description: A warning where the public is advised to take action by seeking cover in protected areas of their homes, schools, or workplaces.
- When using the Shelter in Place Warning, consider the needs of the public who may receive the warning while in transit.
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