Air mass RGB
The Air mass RGB shows the position of the jet streams and subsequent dry descending stratospheric air, shown in a reddish shades.
Warm Air mass with a high tropopause appear as a green shades cold air masses shown in blue shades.
As re-intensification occurs over the Atlantic an interesting phenomena occurs, between 6 August 09:12 and 21:12 UTC. The upper level cirrus shield moves southeast and decays. However the low level cloud bulge, shown as a greenish cloud mass (warm tropical air) extending from beneath the extra-tropical storms cirrus shield moves under the jet stream shown in red. As this interaction takes place we see the first signs of an emerging cloud head, signifying rapid cyclogenesis is occurring. As development continues the jet core continues to brighten, signifying further stratospheric intrusion and engagement of polar air.