The November 16, 2015 High Plains Tornado Outbreak: Forecasting a Highly Anomalous Severe Weather Event

Prior to November 2015, no EF-3 tornadoes had ever been documented in the month of November west of the 100--W meridian line. This changed on 16 November 2015, when numerous tornadoes were documented to have occurred in the region with three EF-3 tornadoes documented. This was part of a larger outbreak that spanned from West Texas, into western Oklahoma and into western Kansas. There were many challenges forecasting this event, including poor model performance and anomalous environmental conditions that would determine storm morphology. Analog climate signals had suggested an outbreak would be possible on this date, but they were too far east and south due to no such record of them occurring in the region in November. The timing of forcing from the approaching deepening trough and advection of anomalous low level moisture resulted in this highly unusual event. This presentation will explore the convergence of meteorological parameters, the performance of weather models, and the deciding factors that helped the office forecast this event.