Within the cellular cold air cloudiness behind the cold front, there is an area over Northern Ireland reaching north-westwards where the tops of cells are colder. This is typical Enhanced Cumuli cloudiness (EC) (compare Enhanced Cumulus ). The characteristic key parameters and key parameter combinations are:

Rel.Top. + TA=<0	This combination gives an overview at the larger scale situation; typically ECs can be found within the thickness troughs on the rear of the Cold Front mostly within cold advection CA 500/1000 hPa
PVA500>=2	Positive vorticity advection (PVA) at 500 hPa exceeding a threshold of 2 units (*10-9 sec-2); well developed cases show up with pronounced PVA maxima which can also be followed prognostically
Isot + PVA300>=3	This is a combination of isotachs greater than 30 units (m sec-1) and positive vorticity advection (PVA) at 300 hPa exceeding 3 units (*10-9 sec-2); this combination indicates a special situation where ECs can develop, namely in the left exit region of jet streaks

All key parameters show in this case a typical behaviour for the development of EC cloudiness. It is situated in the centre of a small-scale thickness trough (white isolines), in the maximum of cold advection (CA) (red dashed lines) and it coincides with a separate PVA maximum (yellow) at 500 hPa. A comparison with the jet streak situation (compare Intensification of cold front through jet streak crossing ) confirms that in addition to curvature, the EC is also under the influence of a left exit region of the Atlantic jet streak.