Forecasting Tornado Outbreaks vs. Derecho in the Northeast 

Patterns  

Forecasting Tornado Outbreaks vs. Derechos in the Northeast 

Introduction

Data and Methodology

Patterns

Storm Relative Wind Flow

References

Cases for the tornado outbreaks (4) and derecho cases (2) were divided into similar types with several composite charts for each type presented below.  You can find more charts and analyses at different levels of the atmosphere in Sheryl Honikman's Masters Thesis titled Forecasting Synoptic and Mesoscale Environments for Tornadoes and Derechos in the Northeast United States.  It is available at the University at Albany Library. 

Composite Charts

Tornado Cases - 500 hPA heights and absolute vorticity (*10^-5) for grouping A (upper left), B (upper right), C (lower left) and D (lower right)

Tornado Cases - 200 hPA heights and isotachs (kt) for grouping A (upper left), B (upper right), C (lower left) and D (lower right)

Derecho Cases - 500 hPA heights and absolute vorticity (*10^-5) for grouping A (left) and B (right)

Derecho Cases - 200 hPA heights and isotachs (kt) for grouping A (left) and B (right)