Not a Tornado -- Yet | NBC 10 Philadelphia

Not a Tornado -- Yet

So much storm damage has many asking if our area was hit by a tornado

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    NEWSLETTERS

    Chris Zabaska
    I am enclosing some pictures I took at Spring Ford Area High School in Royersford Montgomery County of weather related damage on Wednesday, July 29, 2009.

    Was it a tornado? The short answer is no, or at least not yet.

    The Doppler in Doppler radar stands for the Doppler effect. The radar is able to determine if the returned echo -- from the rain or hail -- are moving towards or away from the radar. This effect would make it possible to determine if there is rotation in a thunderstorm, an indication of a storm that could produce a tornado.

    Wild Weather Topples Trees, Power Lines

    [PHI] Wild Weather Topples Trees, Power Lines
    Strong storms roared through the area Wednesday sending trees crashing into houses and snapping power lines. (Published Wednesday, July 29, 2009)

    Rotation detected by radar along with a few other factors could result in a tornado warning issued by the local National Weather Service office. There were no tornado warnings issued today, just a number of severe thunderstorm warnings. Those warnings are issued if a storm looks capable of producing hail 3/4 of an inch and or wind gusts over 57 m.p.h.

    If a tornado warning was issued or an actual tornado was detected by a trained spotter, then the National Weather Service would send out a team to investigate the damage and determine if there was a tornado at all, and if so what class of tornado it was -- depending on the damage.

    Even though there appeared to be no tornadoes today, damage reports are still coming in. There was still a good deal of thunderstorm wind damage. A non-tornadic storm could still produce winds greater than 70 m.p.h., as was the case Wednesday.

    In Monroe County, there was a tornado that caused a good bit of damage. The cell phone video's posted exclusively on the Morning Call's Web site.

    Check the latest storm reports at the National Weather Service in Philadelphia or the Storm Prediciton Center.

    Dave Warren is a meterologist for NBC Philadelphia.