The flight was tasked by Garda Operations The normal operational height was between 800/1000 feet above ground level. Some 9 miles north of Ennis, Co. Clare the helicopter inadvertently entered cloud and, in reacting, the pilot quickly raised the collective pitch lever, the aircraft yawed and climbed and levelled off at 1700 feet in IMC. With the weather conditions worse than forecast the pilot decided to return to Shannon Airport and flew on a heading of 175º back to that airport. However, the radar operator at Shannon issued a correction to this heading of some 90º which the pilot followed. He landed back at Shannon Airport at 0040 hours.