Conceptual Model: Rapid Cyclogenesis

1. Conceptual Model: Rapid Cyclogenesis How to use MSG satellite images similarities to and improvements over MTP Contact person: Veronika Zwatz-Meise zwatz-meise@zamg.ac.at Version 1.0. 13 July 2004

2. CM:Rapid cyclogenesis • MTP channels in comparison with the corresponding MSG channels • CM Rapid cyclogenesis: IR image + relevant NWP parameters • MSG additional channels + Channel combinations • (WV and WV difference images)

3. IR sequence • Multilevel frontal cloud band • Low cloud head at rear side of frontal cloud band • Rapid dissolution of cloud at the rear side of the low cloud head • Rapid development of spiral structure • Development of Cbs at developed cloud spiral

4. MTP: IR/03 UTC As the image time between MTP and MSG differs, a shift between the cloud systems can be noticed in the two images

5. Sharper contours through improved space resolution; consecutive sequence only from MSG MSG: CH09/03 UTC

6. MSG: CH09/06 UTC

7. MSG: CH09/09 UTC

8. MSG: CH09/12 UTC

9. MSG: CH09/15 UTC

10. MSG: CH09/18 UTC

11. WV sequence • Dark stripe in WV approaches the cloud head area • Dark stripe becomes darker and begins to dissolve cloud at the rear edge of the cloud head area • In Ch05 double structure of the dark stripe with different developments visible • Refinement of CM possible ?! • Development of a dark area in the spiral center

12. MTP: WV/03 UTC

13. Sharper contours through improved space resolution; consecutive sequence only from MSG; In MSG two WV channels: Ch05: WV information from high layers MSG: CH05/03 UTC

14. MSG: CH05/06 UTC

15. MSG: CH05/09 UTC

16. MSG: CH05/12 UTC

17. MSG: CH05/15 UTC

18. MSG: CH05/18 UTC

19. In MSG two WV channels Ch06: gives more information from lower layers when comapres Ch05; double structure of black stripes only in last time period resognisable - downward protrusion of dry air MSG: CH06/03 UTC

20. MSG: CH06/06 UTC

21. MSG: CH06/09 UTC

22. MSG: CH06/12 UTC

23. MSG: CH06/15 UTC

24. MSG: CH06/18 UTC

25. CM:Rapid Cyclogenesis • MTP Satellite images • MTP channels in comparison with the corresponding MSG channels • CM Rapid cyclogenesis: IR/WV image + relevant NWP parameters • MSG additional channels + Channel combinations • (WV and WV difference images)

26. Ch09; equ.thickness TFP Frontal characteristics in high gradient of thickness and TFP; high thickness gradient in cloud head area

27. Ch09; TA 700 hpa Frontal characteristics well seen in TA at 700 hPa: WA shield and CA behind CF

28. Ch09; Height contours 1000 hPa Distinct pressure minimum close to the surface (1000 hPa)

29. Ch09; height contours 500 hPa Upper level trough at the rear side of the cloud head

30. Ch09; jet streak 300 hPa Distinct jet streak from N, NW; bending to western orientation; cloud head in exit region

31. Ch09; jet streak PVA 300 hPa Distinct PVA max at 300 hPa in left exit region of the jet streak and in the cloud head area; PVA max close to the jet axis: shear and curvature vorticity

32. Ch09; height of PV = 2 units Stratospheric air (PV =2) down to 600 hPa behind the cloud head; this corresponds to the dark stripe in the WV image

33. Ch05; zeroline of shear vort. 300 hPa CH05: WV in high layers Zeroline of shear vorticity is somewhat on the anticyclonic side of the black stripe

34. Ch06; zeroline of shear vort. 300 hPa CH06: WV in lower layers than in Ch05 Zeroline of shear vorticity is at the boundary between dry and humid air; WV boundary is inclined upward; dry air tilted with height

35. CM:Rapid Cyclogenesis • MTP Satellite images • MTP channels in comparison with the corresponding MSG channels • CM Rapid cyclogenesis: IR image + relevant NWP parameters • MSG additional channels + Channel combinations • WV and WV difference images

36. 134 Frontal cloudband: brown:multilayered Cloud head: yellow: low brown: beginning convection and spiral structure

37. 139 Frontal cloudband: violet: multilayered Cloud head: yellow: low violet: beginning convection and spiral structure