Thundersnow

2013-01-31 19:42:37.000 – Michael Kyle,  Summit Intern

Over the past few days many of the interior states from the Gulf Coast to the Ohio River Valley have seen unusual severe weather. According to the Storm Prediction Center’s website there have been 736 storm reports from January 29th through January 30th. Of these reports 30 have been tornados, 643 of strong winds, and 13 of hail. The occurrence of thunderstorms in these areas of the country is not abnormal however, it is unusual to see severe thunderstorms in January. So it got me wondering; has Mount Washington ever seen thunderstorms during the month of January? The simple answer is yes, but they are rare and aren’t your topical thunderstorms.

According to the Mount Washington Observatory’s historical records there have been a total of eleven thunderstorms observed during the month of January between 1934 and present. However as I alluded to earlier these were not typical thunderstorms as all of them were observed during a snow event making them something more commonly known as “thundersnow”.

Thunderstorms and thundersnow are basically the same in that they both require the same three main ingredients of moisture, instability, and a lifting mechanism. The main difference is thunderstorms occur under warmer weather conditions and are fairly common during the summer months, while thundersnow occurs in colder weather and is much more rare. The reason for this is due in part to generally cold air that is typically more stable and is not capable of holding much moisture. Therefore two of the three key ingredients are harder to come by at any one time.

So the next time its snowing heavy and you think you hear a clap of thunder or see a flash on lightning, consider yourself “lucky”. You probably just experienced a rare thundersnow event.

Michael Kyle,  Summit Intern