How Severe Weather Can Develop in Central MN
Severe weather is a possibility for portions of Minnesota Wednesday. I talked with meteorologist Megan Mulford from the National Weather Service. She says to have a thunderstorm 3 ingredients are needed; moisture, instability and lift. She says high dew points and humidity can also contribute.
Instability
Mulford says the instability happens when you have heat at the surface that warms and cools a lot and a lift is a frontal system that can be a jet stream. Mulford says severe weather often comes after a cold front. She says a front is a clash of 2 air masses.
Moving West to East
Weather in our area moves primarily from west to east. Megan says it is because the United States is part of the westerlies which means the jet streams in the northern part of the hemisphere blows from west to east. She says part of western Africa along the Atlantic Ocean is where the easterlies are located. She says that's why you see hurricanes go from east to west until they get caught up in the westerlies.
Hurricanes
Mulford says that's why you see hurricanes hit the gulf coast and Texas and then move east. She says it is rare to see storms move from east to west in Minnesota but it can happen if they are on the top of a high pressure system because high pressure systems go clockwise. Mulford says most storms move along the low pressure system and that can bring those storms northwest or southwest as it follows the cold front.
Hear my complete conversation with Megan Moulford below.