FM 15020KT

When you can't go flying because of the weather, you study the weather.  But how would you decipher the phrase in a Center Weather Advisory:

• AREA EMBD OF TS AND SHRA WITH MOD-HVY PCPN MOV FM 15020KT

I still cannot find the definitive resource but an FSS 1800wxbrief briefer and I discussed it at length today.  I would love to see it in writing!