Case Study 14 - 15 June 1998

• I. Initial state 14 June 1998/06.00 UTC: SatRep diagnosis
• Overview of satellite features and conceptual models
• 14 June/06.00 UTC: Frontal Diagnosis
• II.14 June 1998/06.00 UTC - 15 June 1998/06.00 UTC: The development of the front and detailed frontal diagnosis
• VSRF: 14 June 06.00 - 18.00 UTC
• 14 June/18.00 UTC: Frontal diagnosis
• 15 June/00.00 UTC: Frontal diagnosis
• 15 June/06.00 UTC: Frontal diagnosis
• VSRF: 15 June 06.00 - 18.00 UTC
• III. 15 June 1998/12.00 - 18.30 UTC: Unstable situation MCS
• Overview of satellite features at the synoptic scale during the observation period
• The observational part of MCS diagnosis - IR image sequence
• The synoptic environment part of MCS diagnosis - 15 June/12.00 and 18.00 UTC
• IV. Conclusions

Overview of satellite features at the synoptic scale during the observation period

The following images (Fig. I00a-I00c) show the development of intensive MCS's, initially southeast of the Baltic States (56N/30E - 57N/36E) which, later in the evening, move towards Estonia and further over Finland. The large synoptic-scale frontal systems were located as follows:

• A Warm Front cloud band was located over Finland and Sweden, and it was accompanied by precipitation.
• A Cold Front cloud band was located over White Russia - Ukraine - Russia, and it was accompanied by rain and thunderstorms.
• A CCB Occlusion was located over Romania - Ukraine, and it was accompanied by precipitation.

The development of MCS's within the warm air-mass was rapid resulting in huge multiple MCS in southern Finland, Estonia and White Russia. Many thunderstorms were observed within these MCS's.

15 June 1998/12.00 UTC - Meteosat IR image; weather events (green: rain and showers, blue: drizzle, cyan: snow, red: thunderstorm with precipitation, purple: freezing rain, orange: hail, black: no actual precipitation or thunderstorm with precipitation)	15 June 1998/15.00 UTC - Meteosat IR image; weather events (green: rain and showers, blue: drizzle, cyan: snow, red: thunderstorm with precipitation, purple: freezing rain, orange: hail, black: no actual precipitation or thunderstorm with precipitation)
15 June 1998/18.00 UTC - Meteosat IR image; weather events (green: rain and showers, blue: drizzle, cyan: snow, red: thunderstorm with precipitation, purple: freezing rain, orange: hail, black: no actual precipitation or thunderstorm with precipitation)