diff --git a/lib/xmet/skew_t.py b/lib/xmet/skew_t.py
index 1a47c52..e06f47b 100644
--- a/lib/xmet/skew_t.py
+++ b/lib/xmet/skew_t.py
@@ -58,7 +58,7 @@ class SkewT():
 
         return x + y, y
 
-    def draw_pressure_lines(self, cr: cairo.Context, x: float, y: float):
+    def draw_isobars(self, cr: cairo.Context, x: float, y: float):
         for pressure in range(PRESSURE_MIN, PRESSURE_MAX+1, PRESSURE_STEP):
             coord = self.graph_to_screen(-self.width / 2,
                                          self.pressure_y(pressure))
@@ -86,4 +86,4 @@ class SkewT():
 
     def draw(self, cr: cairo.Context, x: float, y: float):
         self.draw_isotherms(cr, x, y)
-        self.draw_pressure_lines(cr, x, y)
+        self.draw_isobars(cr, x, y)