Summary
The case study presents an interesting development of a rapid cyclogenesis. The storm cyclone leads to heavy devastation over the High Tatra Mountains on 19 November 2004. Some days before, the beginning of the entire development is indicated by an induced wave over the Atlantic Ocean.
Upper air processes like a strong jet stream and downward-protruding dry air play a crucial role in the further development.
Following conclusions can be summarised:
- Downward-protruding stratospheric air and strong upper winds interact with a low-level baroclinic zone, which leads to a rapid development of a storm cyclone.
- A strong horizontal temperature contrast plays an important role in the development of the wave.
- The area of the development coincides with the left exit region of a jet streak.
- Strong maxima of PVA can be found in the left exit region of the jet streak, contributing to upward motion.
- Over Europe a wide over-running of upper dry stratospheric air above the surface front leads to the formation of a typical split front.
- Strong surface winds are connected to the cyclogenesis, especially over the High Tatra Mountains where orographic processes play an enforcing role.
- The cloud configuration is characterized by an emerging cloud head on the poleward side of the polar front cloud band. The development fits the conceptual model of a rapid cyclogenesis rather well.