Under which condition does the Snow Emergency Plan NOT take effect?

The Snow Emergency Plan for a fire department is typically activated under specific conditions that directly relate to snowfall and road safety. A freeze warning issued by the National Weather Service does not automatically trigger the Snow Emergency Plan, as it primarily indicates low temperatures that can lead to ice formation but does not necessarily correlate with heavy snowfall or hazardous road conditions.

The other scenarios listed are related to significant snowfall or hazardous road conditions, which are the primary concerns that necessitate activating the Snow Emergency Plan. Therefore, the action of issuing a freeze warning alone does not meet the criteria for initiating the plan, making this choice the correct answer.