A winter storm blasted the Northeast and has caused havoc with the roads and power in the State of Connecticut. Evidently the state must have asked the President for an Emergency Declaration in order to bring Federal resources to bear in responding to the emergency.
This is different from a Presidential Declaration of a Disaster. A disaster declaration has more to do with recovery and commits Federal resources to help with the typical 75-25% Federal/State & Local match for disaster recovery costs.
With the emergency declaration FEMA can commit people and other resources to assist in the response. Typically you might see these types of emergency declarations for wildland fires, at least that is my experience.