Hi,
Yes it is possible.use the following code to create workflow using alfresco script.
function startWorkflow(){
var workflow = actions.create("start-workflow");
workflow.parameters.workflowName = workflowName;
workflow.parameters["bpm:workflowDescription"] = "Critical event:"+document.name;
workflow.parameters["bpm:groupAssignee"] = groupName;
var dueDate = new Date();
//dueDate.setDate(dueDate.getDate()+1);
workflow.parameters["bpm:workflowDueDate"] = dueDate;
workflow.parameters["bpm:workflowPriority"] = 3;
workflow.execute(document);
}