People tend to associate lightning and thunder to spring and summer thunderstorms. But, we can also, have lightning and thunder with snow storms as well.
The last couple of snow storms we have had several instant messages, tweets and emails about people hearing thunder as the storms were ramping up. This is a phenomenon known as "Thundersnow" and happens in many areas of the United States.
Now, not all snow storms can produce thunder and lightning. You need a system that is capable of producing convection. The ingredients that come together have to do so in a very precise manner. First you have cold air aloft and on the ground, the tricky part is that even though ground temperature is cold, it is still warmer than the air aloft and tends to rise. This feeds instability in the storm system. Meaning you have rising air shooting up into the atmosphere. And just as with summer thunderstorms if there is moisture in that rising air you are going to have some type of condensation and eventually, precipitation. And since, temperatures in a cold winter storm are cold enough in the air and on the ground that precipitation should fall as snow. Other ingredients that help to make the air rise can include a strong advancing cold front and in our case the mountains.
Typically, along the Front Range when we have a convective snow storm we can see a lot more snow in localized areas. So, snowfall measurements can vary greatly. You may have only 8 inches of snow in one area as opposed to 20 inches in others. Much the same way in summer storms, when one side of town may only see a trace of rain and the other enough to flood the streets.
If you have anymore questions about Colorado Weather please check out "Colorado Weather Inside Out" at the bottom right had column of the weather page at cbs4denver.com.