That only means the signal return is 200 times, not the rain is 200 times.
We're talking milliwatts here. WABC AM770 radio broadcasts at 50,000 watts, albeit at a MUCH lower frequency.
I found some numbers on precipitation rates based on the strength or the radar return.
magenta: 65 dBZ (extremely heavy precipitation, > 16 in (410 mm) per hour, but likely hail)
red: 50 dBZ (heavy precipitation of 2 in (51 mm) per hour)
yellow: 35 dBZ (moderate precipitation of 0.25 in (6.4 mm) per hour)
green: 20 dBZ (light precipitation)
WWG1WGA
Garde la Foi, mes amis! Nous nous sommes les sauveurs de la République! Maintenant et Toujours!
(Keep the Faith, my friends! We are the saviors of the Republic! Now and Forever!)
LonePalm, le Républicain du verre cassé (The Broken Glass Republican)