(A) Experimentally measured H3K27me3 levels in NR (peak), and elsewhere across FLC (body), during and 7 d after cold for uninterrupted cold periods of 2 wk, 4 wk, 6 wk, and 8 wk. Also shown are simulated H3K27me3 levels for digital and analog models. (B) Experimentally measured levels of spliced FLC mRNA (expression) 7 d after cold relative to nonvernalized (NV), i.e., with no exposure to cold, values for uninterrupted cold periods of 2 wk, 4 wk, 6 wk, and 8 wk. Also shown are simulated relative mRNA levels for digital and analog models. Experimental error bars are SEM, with n = 5 for body H3K27me3 levels; n = 7, 7, 9, 5, and 8 for peak levels immediately after 0 wk, 2 wk, 4 wk, 6 wk, and 8 wk cold; n = 7, 8, 5, and 7 for peak levels following 2 wk, 4 wk, 6 wk, and 8 wk cold and a 7-d period of warm; and with n = 8, 13, 10, and 8 for relative expression 7 d after 2 wk, 4 wk, 6 wk, and 8 wk cold, respectively.