Greatest pressure drop measured in a tornado

According to Official Guinness Records,

On 21 April 2007, a series of tornadoes broke out across Texas, USA. One of these, an EF2, hit a mobile mesonet vehicle that was gathering scientific data in the town of Tulia. The instruments on the vehicle recorded a pressure drop inside the vortex of 194 millibars or 0.194 bars (5.72 inches of mercury).The mobile mesonet vehicle sustained significant damage from the tornado encounter.

For a complete list of 2007 records, please visit 2007 Guinness Records in United States.

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