Strong winds created damage across many communities this morning as a line of storms rolled through the area. Trees were uprooted-- some onto cars, roads and homes. In some communities, the damage was more extreme. You can see parts of a roof blocking the street and debris sprinkled across this neighborhood. A large recreational vehicle was blown over and thrown into property down the street. This particular cell was tornado warned at about 8:00 AM. The National Weather Service issued several tornado warnings earlier today and in Carroll County-- they sent a crew out to survey the damage.
Our Weather Team was tracking those storms for you this morning and we noticed these rotation signatures. Here's a look at the traditional radar as you typically see it on a regular day. You can see the bands of heavier precipitation displayed by the darker reds. There is a little notch that occurs in the vicinity of Westminster, and that was a first clue of some sort of rotation.
When we take a look at storm relative velocity, we can determine the speed...and most importantly the direction of the winds in the storm. Here you can see the green, which indicates winds blowing toward the radar beam, and the red illustrating winds blowing away from the radar beam. In a normal storm, we would typically see both of these colors...but because these colors are "coupled" together so tightly...with significant brightness contrasts (the area circled)...we were able to determine there was significant rotation in the area. Admittedly the radar beam is high up, so that rotation that we are seeing is above ground, and above ground rotation doesn't always make it to the surface.
So we take a look at another level. We're able to look at correlation coefficient. It allows us to see the uniformity of the atmosphere. The solid red indicates an area where the atmosphere is essentially experiencing the same feature, but where we see the spikes near Mountain Lake View, there is something abnormal here. Sometimes it could be something as simple as birds flying in the area, but when combined with the other layers we've shown, it is more likely that this is some sort of debris being thrown into the air.
The National Weather Service in Leesburg confirmed this evening that this indeed was an EF-1 tornado. It traveled northeast through downtown Westminster... essentially paralleling Ridge Road and Union Street. The maximum winds were estimated at 90 mph.
Elsewhere, the National Weather Service was able to confirm a tornado in Cecil County this morning associated with this same line of storms. That tornado has been rated as an EF-1. Our weather team was sending out alerts this morning via twitter before the cell was officially warned.