[MilCom] Washington DC Visual Warning System Operations?

[Ken]

See news release at:
http://www.faa.gov/news/news_home/visual_warning/
http://www.norad.mil/index.cfm?fuseaction=home.news_rel_05_24_05
http://www.norad.mil/index.cfm?fuseaction=home.news_fact_vws

Now technically the mystery is how does it operate???

My guess, I'd assume that the equipment is mounted on high tower/ high 
building some sort of radio microwave/wire fiber optic link back to the 
radar control computer which would determine the closest laser to "paint" 
the target.

Also wonder how many of these $500K per unit, units are deployed.  I'd guess 
four to six?

Furthermore, doesn't weather conditions (e.g. cloud cover, rain, snow) 
seriously impact a system like this?

Ken