After another steamy day with heat indexes reaching into the triple digits in New Jersey, strong storms are expected to develop across the state with warnings for northwestern counties. The National Weather Service in Mount Holly issued severe storm warnings for Warren, Sussex and Morris counties Saturday afternoon. A storm cell was identified over Blairstown around 1:30 p.m. moving at a quick pace and capable of producing 60 mile-per-hour wind gusts and quarter-size hail, officials said in an afternoon weather update. The entire state is under a severe thunderstorm watch with the potential fo…