02 - 03 August 1997 - Summary

Summarizing, one can say that two different upper level phenomena exist in this region:

  • The jet streak with a PVA maximum in the left exit region - a phenomenon which is not only connected with the intensified cloudiness and weather over Ireland but possesses also the potential for further Rapid Cyclogenesis development;
  • A small scale cut off low (Upper Level Low) immediately at the rear which is recognised by wet and dry upper level features and shows a somewhat different propagation direction indicated by a PVA maximum at 500 hPa.

While the development of a Rapid Cyclogenesis has stagnated, during the last 18 hours the development of an Upper Level Low was quite intensive. But the physical situation, especially on isentropic surfaces, cannot exclude the possibility of a Rapid Cyclogenesis development in the next time period.