September 4, 20171430.18z
UNISYS Water Vapor Satellite of the north and west hemisphere
The shadow storm shows up best in this satellite picture just north and west of Irma. It started quite differently. It can be seen in the image below as a shadow in the same location (north-west of Irma), but, more diffuse.
September 3, 20171330.18z
UNISYS Water Vapor Satellite of the north and west hemisphere
September 4, 20170815.18z
UNISYS Water Vapor Satellite of the north and west hemisphere
The top image (September 4, 1430) followed the satellite image above. It was in the image below (September 4, 2330) when Irma's velocity east over took the shadow storm and it is viewed directly north of Iram.
September 4, 2017
2330.19z
UNISYS Water Vapor Satellite of the north and west hemisphere
In the image below of September 5, 0530.19z the shadow storm has consolidated north of Irma and gained water vapor content.
September 5, 20170530.19z
UNISYS Water Vapor Satellite of the north and west hemisphere
In the next image of September 5, 1130.18z the shadow storm is more diffuse, but, still evident. I believe these shadow storms draw in necessary water vapor to assist the larger storm. The shadow storm has not completely gone. It may very well reorganize with more water vapor yet again.
September 5, 20171130.18z
UNISYS Water Vapor Satellite of the north and west hemisphere
This is the current image below and just an hour later Irma's shadow storm is looking as though it is gaining water vapor content.
September 5, 20171230.18z
UNISYS Water Vapor Satellite of the north and west hemisphere (click here for 12 hour loop - thank you)
It is an oscillation system that has a push me - pull you relationship to increase water vapor content as the physics of heat demands it. There is that other system behind Irma in the water vapor trail. That system is nearer Africa and could develop into an independent storm as well. I do not think the shadow storm will become an independent system at this point.
The climate is complicated these days.
