New Glarus and the surrounding Green County area could see two rounds of thunderstorms Monday, including a potentially significant period of severe weather during the late afternoon and evening.

The National Weather Service said a broken line of storms was expected to move through southwestern Wisconsin during the morning. Those storms could produce brief heavy downpours, frequent lightning and isolated wind gusts of 50 to 60 mph, although widespread severe weather was considered unlikely during the morning round.

What happens after those storms will play a major role in determining the severity of the evening weather. Forecasters expect a relative lull between approximately noon and 5 p.m., allowing the atmosphere time to recover.

If clouds and rain linger through much of the afternoon, the atmosphere may remain relatively stable and the evening severe-weather threat would decrease substantially. However, clearing skies and rising temperatures could provide enough energy for numerous strong or severe thunderstorms to develop.