diff --git a/bin/weewx/wxservices.py b/bin/weewx/wxservices.py
index e392749a..10730677 100644
--- a/bin/weewx/wxservices.py
+++ b/bin/weewx/wxservices.py
@@ -77,9 +77,16 @@ class StdWXCalculate(weewx.engine.StdService):
                 calc = True
             if calc:
                 getattr(self, 'calc_'+obs)(data_us, data_type)
+        self.adjust_winddir(data_dict)
         data_x = weewx.units.to_std_system(data_us, data_dict['usUnits'])
         data_dict.update(data_x)
 
+    def adjust_winddir(self, data):
+        if 'windSpeed' in data and not data['windSpeed']:
+            data['windDir'] = None
+        if 'windGust' in data and not data['windGust']:
+            data['windGustDir'] = None
+
     def calc_dewpoint(self, data, data_type):
         if 'outTemp' in data and 'outHumidity' in data:
             data['dewpoint'] = weewx.wxformulas.dewpointF(
diff --git a/docs/changes.txt b/docs/changes.txt
index 87a9dc3f..7ac3f5cf 100644
--- a/docs/changes.txt
+++ b/docs/changes.txt
@@ -22,6 +22,8 @@ Fixed bug in calculation of inDewpoint.
 Assign default units for extraHumid3,4,5,6,7, extraTemp4,5,6,7, leafTemp3,4,
 and leafWet1,2.
 
+Use StdWXCalculate to ensure that wind direction is None if no wind speed.
+
 
 3.0.1 12/07/14