Environments Conducive for Severe Convective Winds in Europe

• Main Author: Pacey, George
• Format: Doctoral or Postdoctoral Thesis
• Language: English
• Published: 2020
• Subjects: Iceland
• Online Access: https://research.manchester.ac.uk/en/studentTheses/2048c6ee-3f06-4809-8df0-3f1f7524da25; https://pure.manchester.ac.uk/ws/files/173342047/FULL_TEXT.PDF

The frequency of European convective windstorms and the environments in which they form remains unknown. Convective winds typically onset very quickly giving people very little time to take safety precautions. Further information would help forecasters to provide well-informed information to their clients and the general public. In this dissertation, the environments in which severe convective winds occur in Europe are investigated. A climatology is produced between 2009-2018 using 10,233 quality-controlled and verified severe convective wind reports from the European Severe Weather Database. Reported severe convective wind days have steadily increased from 50 days per year in 2009 to 116 days in 2018. Severe convective winds were reported in every European country except for Iceland with the most frequent reporting across central Europe, particularly Poland. Reporting is most frequent in the summer season, where severe convective winds were reported every other day on average. The pre-storm environment was assessed using 368 proximity soundings from 47 stations across Europe and a clustering technique was used to distinguish different environments. Two environments for severe convective winds occurred: low-shear-high-instability (mostly in the warm season) and high-shear-low-instability (mostly in the cool season). Cells were the most frequent convective organisational mode in the low-shear-high-instability environment accounting for 63% of events. Conversely, in the high-shear-low-instability environment linear systems were the most frequent convective organisational mode accounting for 48% of events.