I found a suspicious cloud shield in CIMSS Satellite blog:
http://cimss.ssec.wisc.edu/goes/blog/archives/12199
Obviously there are transverse bands... but maybe not only...
The structure of the cloud top (in the eastern side of the cloud shield) is quite similar with those we can call as "dusty" cirrus shield which regularly appear in southern Europe with air-stream from North-Africa with dust/high aerosol content in it.
As far as I know there is no reviewed paper/literature about this effect in English, but a report with possible explanation is available here:
http://oiswww.eumetsat.org/WEBOPS/iotm/iotm/20100211_dust/report_kollath.pdf
my earlier posts with cirrus cloud shields with saharan dust, so you can compare the appearence of the clouds:
http://mrstratus.blogspot.hu/2012/02/poros-cirruszok-kornyekunkkon-januar-6.html
http://mrstratus.blogspot.hu/2012/02/20120222-dusty-high-level-clouds.html
"Grainy" structure in the middle of the satellite image.
Source: NASA/MODIS: http://rapidfire.sci.gsfc.nasa.gov/realtime/?calendar
Biomass burning aerosol content (optical thickness according to ECMWF/GMES). Some vegetation fires should have happened close to the west coast of USA/Canada.