From the right image it can be seen that the isentropic surface of 298K is above the lower frontal zone and therefore characteristic of the low cloud area of the northern front, and that 308K is above the southern frontal zone. The situation on both isentropic surfaces at 18 UTC is nearly unchanged from 12.00 UTC (compare 09.00 - 12.00 UTC - Frontal Diagnosis - Relative streams and conveyor belts). There is a sinking dry intrusion from 500 down to 700 hPa over the low cloudiness of the northern frontal zone but intensive rising of a Warm Conveyor Belt over the Aegean Sea and Turkey which is also connected with an extended zone of precipitation. A limiting streamline between the rising warm wet stream from the south (Warm Conveyor Belt) and the sinking cold dry stream from the north (dry intrusion) can be found at the distinct northern and western cloud edges of the bright cloud band.