During the MCS
The analysis of the MCS by satellite imagery between 10 and 12:30 UTC, also suggest strong activity to the west and northwest of the island, where rain could not naturally be measured at the surface. Beside the information from severe storm RGB referred above (Figure 6), the difference between WV6.2 and IR10.8 channels provide an indication of possible overshootings over the ocean (in yellow and red in Figures 11 and 13, at 10:15 and 11 UTC, respectively). It should be noted though, that the High Resolution Visible (HRV) does not show such an irregular topography of cloud tops as very often can be detected with lower solar angles as in this case (Figure 12, at 10:15UTC). It also should be stressed that the suggested area of overshootings is not related to the highest amounts of CRR, which is a derived product and believed to be more informative (Figure 14, at 11:00 UTC).
Figure 11: Meteosat 9 Difference WV6.2 - IR 10.8 on 20/02/2010 at 10:15 UTC. Positive values in yellow and red, depicting overshooting tops.
Figure 12: Meteosat 9 High Resolution Visible on 20/02/2010 at 10:15 UTC.
Figure 13: Meteosat 9 Difference WV6.2 - IR 10.8 on 20/02/2010 at 11 UTC. Positive values in yellow and red, depicting overshooting tops.
Figure 14: Meteosat 9 Convective Rainfall Rate (CRR, in mm/h) from Meteosat 9 on 20/02/2010 at 11:00 UTC.