INDIANAPOLIS - When Tuesday began, severe weather was not expected. A variety of factors came together to produce confirmed EF-1 tornado that struck Plainfield.
Thunderstorms were in the forecast for Tuesday, but they were not expected to become severe.
The Storm Prediction Center did not have Indiana or any other area of the Midwest in a risk zone for severe weather.
That underscores the inexact science of weather forecasting. Sometimes, elements come together to cause severe weather that can't be seen far in advance.
The storm that hit Plainfield and then weakened as it entered Marion and Hamilton counties was fueled by several factors, including but not limited to a nearby low-pressure area, ample moisture, twisting winds with height and pockets of sunshine to fuel instability.
A storm formed and quickly picked up strength in Morgan County. Radar picked up rotation in the storm, but as it moved toward Marion County, that storm weakened.
The second storm formed a little north of the first one, quickly developing a rotating wall cloud and lower-level rotation.
Within minutes, a tornado dropped from that storm.
"At 2:32 was the first report of a touchdown with debris," said StormTeam 6 Chief Meteorologist Kevin Gregory.
The storm raked the eastern side of Plainfield before apparently lifting as it neared the Marion County line, possibly dropping again before lifting and weakening.
No severe weather watches were ever issued, and the conditions that caused the tornado did not last long.
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