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Jets in blazars are an excellent forum for studying acceleration atrelativistic shocks using the highly-variable emission seen across theelectromagnetic spectrum. Our recent work on combining multi-wavelengthleptonic emission models with simulated thermal+non-thermal distributions fromshock acceleration theory has resulted in new insights into plasma conditionsin blazars. This has demonstrated the ability to infer the cyclotron frequency,the plasma density and thus also the Alfven speed, thereby determining therapidity of particle energization. An important inference was that MHDturbulence levels decline with remoteness from jet shocks. This paper outlinesnew results from our recent extension of this program to a two-zone,time-evolving construction, modeling together both extended, enhanced emissionstates from larger radiative regions, and prompt flare events from compactacceleration zones. These are applied to flares in the FSRQ blazar 3C 279monitored by Fermi-LAT in gamma-rays in late 2013. With impulsive injectionepisodes from the shock zone, as the acceleration first proceeds and thenabates, the radiative simulations obtain a pronounced spectral hardening in theoptical and gamma-ray bands as the flare grows, followed by a softening duringthe decay phase. For 3C 279, while model radio and X-ray synchrotron flares aretemporally correlated, there is a lag in both bands relative to GeV gamma raysand optical emission on timescales of a number of hours. This delay is governedby the short cooling time associated with the bright external Compton signal.

Time-Dependent, Multi-Wavelength Shock Acceleration Models for Active Flares of 3C 279