Memorial Day festivities could get soggy on Monday as weather forecasters are predicting possible showers and thunderstorms hitting New Jersey. The Mount Holly station of the National Weather Service is calling for a 30% chance of showers. According to Accuweather, thunderstorms, some of them heavy, are expected Monday afternoon through evening. Forecasters are calling for two rounds of rainy weather for the holiday. After some possible rain in the morning, a cold front late Monday is expected to bring a second, stronger round of showers and thunderstorms into the night. “Severe thunderstorms …