diff --git a/message_definitions/v1.0/development.xml b/message_definitions/v1.0/development.xml
index 36deb98fc7..cf446e5781 100644
--- a/message_definitions/v1.0/development.xml
+++ b/message_definitions/v1.0/development.xml
@@ -13,6 +13,19 @@
       <entry value="1" name="AIRSPEED_SENSOR_USING">
         <description>True if the data from this sensor is being actively used by the flight controller for guidance, navigation or control.</description>
       </entry>
+    </enum>
+      <entry value="43004" name="MAV_CMD_EXTERNAL_WIND_ESTIMATE" hasLocation="false" isDestination="false">
+        <description>Set an external estimate of wind direction and speed.
+          This might be used to provide an initial wind estimate to the estimator (EKF) in the case where the vehicle is wind dead-reckoning, extending the time when operating without GPS before before position drift builds to an unsafe level. For this use case the command might reasonably be sent every few minutes when operating at altitude, and the value is cleared if the estimator resets itself.
+        </description>
+        <param index="1" label="Wind speed" units="m/s" minValue="0">Horizontal wind speed.</param>
+        <param index="2" label="Wind speed accuracy" units="m/s">Estimated 1 sigma accuracy of wind speed. Set to NaN if unknown.</param>
+        <param index="3" label="Direction" units="deg" minValue="0" maxValue="360">Azimuth (relative to true north) from where the wind is blowing.</param>
+        <param index="4" label="Direction accuracy" units="deg">Estimated 1 sigma accuracy of wind direction. Set to NaN if unknown.</param>
+        <param index="5">Empty</param>
+        <param index="6">Empty</param>
+        <param index="7">Empty</param>
+      </entry>
     </enum>
     <enum name="RADIO_RC_CHANNELS_FLAGS" bitmask="true">
       <description>RADIO_RC_CHANNELS flags (bitmask).</description>