diff --git a/lib/xmet/skew_t.py b/lib/xmet/skew_t.py
index 98fc1f4..4ce35de 100644
--- a/lib/xmet/skew_t.py
+++ b/lib/xmet/skew_t.py
@@ -51,14 +51,14 @@ class SkewTGraph():
     def draw_isobars(self, cr: cairo.Context, x: float, y: float):
         cr.save()
 
+        cr.set_source_rgb(0.75, 0.75, 0.75)
+
         for pressure in range(PRESSURE_MIN, PRESSURE_MAX+1, PRESSURE_STEP):
             coords = self.graph_to_screen(-self.width / 2,
                                          self.pressure_to_y(pressure))
 
-            if pressure % (2*PRESSURE_STEP) == 0:
-                cr.set_source_rgb(0.35, 0.35, 0.35)
-            else:
-                cr.set_source_rgb(0.75, 0.75, 0.75)
+            if pressure % (2*PRESSURE_STEP) != 0:
+                continue
 
             cr.move_to(x + coords[0], y + coords[1])
             cr.rel_line_to(self.width, 0)