Conceptual Model Rapid Cyclogenesis How to use MSG

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 1

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) 2

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 3

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 4 images

MSG: CH 09/03 UTC Sharper contours through improved space resolution; consecutive sequence only from MSG 5

MSG: CH 09/06 UTC 6

MSG: CH 09/09 UTC 7

MSG: CH 09/12 UTC 8

MSG: CH 09/15 UTC 9

MSG: CH 09/18 UTC 10

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 Ch 05 double structure of the dark stripe with different developments visible – Refinement of CM possible ? ! • Development of a dark area in the spiral center 11

MTP: WV/03 UTC 12

MSG: CH 05/03 UTC Sharper contours through improved space resolution; consecutive sequence only from MSG; In MSG two WV channels: Ch 05: WV information from high layers 13

MSG: CH 05/06 UTC 14

MSG: CH 05/09 UTC 15

MSG: CH 05/12 UTC 16

MSG: CH 05/15 UTC 17

MSG: CH 05/18 UTC 18

MSG: CH 06/03 UTC In MSG two WV channels Ch 06: gives more information from lower layers when comapres Ch 05; double structure of black stripes only in last time period resognisable downward protrusion of dry air 19

MSG: CH 06/06 UTC 20

MSG: CH 06/09 UTC 21

MSG: CH 06/12 UTC 22

MSG: CH 06/15 UTC 23

MSG: CH 06/18 UTC 24

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) 25

Ch 09; equ. thickness TFP Frontal characteristics in high gradient of thickness and TFP; high thickness gradient in cloud head area 26

Ch 09; TA 700 hpa Frontal characteristics well seen in TA at 700 h. Pa: WA shield and CA behind CF 27

Ch 09; Height contours 1000 h. Pa Distinct pressure minimum close to the surface (1000 h. Pa) 28

Ch 09; height contours 500 h. Pa Upper level trough at the rear side of the cloud head 29

Ch 09; jet streak 300 h. Pa Distinct jet streak from N, NW; bending to western orientation; cloud head in exit region 30

Ch 09; jet streak PVA 300 h. Pa Distinct PVA max at 300 h. Pa 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 31

Ch 09; height of PV = 2 units Stratospheric air (PV =2) down to 600 h. Pa behind the cloud head; this corresponds to the dark stripe in the WV image 32

Ch 05; zeroline of shear vort. 300 h. Pa CH 05: WV in high layers Zeroline of shear vorticity is somewhat on the anticyclonic side of the black stripe 33

Ch 06; zeroline of shear vort. 300 h. Pa CH 06: WV in lower layers than in Ch 05 Zeroline of shear vorticity is at the boundary between dry and humid air; WV boundary is inclined upward; dry air tilted with height 34

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 35

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

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