diff --git a/scripts/draw_events.py b/scripts/draw_events.py
index de890acda04994d424464b337855b95508251894..c7b63b46ccdb70a7a97d8f8c98a5d31319fad963 100644
--- a/scripts/draw_events.py
+++ b/scripts/draw_events.py
@@ -59,7 +59,7 @@ parser.add_argument('output_dir', help='Output directory')
 parser.add_argument('-e', dest='event', help='specify an event number to plot', type=int)
 parser.add_argument('-n', dest='nevents', help='number of random events to plot', type=int, default=10)
 parser.add_argument('--time-min', dest='tmin', help='lower limit of the time window, default 0', type=int, default=0)
-parser.add_argument('--time-max', dest='tmax', help='upper limit of the time window, default 192 (max)', type=int, default=192)
+parser.add_argument('--time-max', dest='tmax', help='upper limit of the time window, default 191 (max)', type=int, default=191)
 
 args = parser.parse_args()
 
@@ -124,6 +124,7 @@ for iev in evs:
         ax.patch.set_alpha(pmt_colors[pmt[i]][1])
 
         sp = samples[ch[i]]
+        lines, labels = [], []
         if len(sp) > 0:
             pp = pprops[ch[i]]
             ax.plot(np.arange(len(sp)), sp, label='Waveform Data')