diff --git a/Environment/clouds-altitude-interpolate.xml b/Environment/clouds-altitude-interpolate.xml
new file mode 100644
index 000000000..1bcd1b1fe
--- /dev/null
+++ b/Environment/clouds-altitude-interpolate.xml
@@ -0,0 +1,41 @@
+<?xml version="1.0" ?>
+<!--
+ This file is part of FlightGear, the free flight simulator
+ http://www.flightgear.org/
+
+ Copyright (C) 2009 Torsten Dreyer, Torsten (at) t3r _dot_ de
+
+ This program is free software; you can redistribute it and/or
+ modify it under the terms of the GNU General Public License as
+ published by the Free Software Foundation; either version 2 of the
+ License, or (at your option) any later version.
+
+ This program is distributed in the hope that it will be useful, but
+ WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ General Public License for more details.
+-->
+<PropertyList>
+  <params>
+    <from>environment/metar/clouds/layer[0]/elevation-ft</from>
+    <to>/environment/clouds/layer[0]/elevation-ft</to>
+  </params>
+  <name>MetarController:clouds:altitude_interpolate</name>
+  <type>noise-spike</type>
+  <max-rate-of-change>8.333</max-rate-of-change>
+  <enable>
+    <condition>
+      <property>/environment/metar/valid</property>
+      <greater-than>
+        <property alias="../../../../params/from"/>
+        <value>-9000</value>
+      </greater-than>
+      <greater-than>
+        <property alias="../../../../params/to"/>
+        <value>-9000</value>
+      </greater-than>
+    </condition>
+  </enable>
+  <input alias="../params/from"/>
+  <output alias="../params/to"/>
+</PropertyList>
diff --git a/Environment/clouds-altitude-set.xml b/Environment/clouds-altitude-set.xml
new file mode 100644
index 000000000..edd834a49
--- /dev/null
+++ b/Environment/clouds-altitude-set.xml
@@ -0,0 +1,43 @@
+<?xml version="1.0" ?>
+<!--
+ This file is part of FlightGear, the free flight simulator
+ http://www.flightgear.org/
+
+ Copyright (C) 2009 Torsten Dreyer, Torsten (at) t3r _dot_ de
+
+ This program is free software; you can redistribute it and/or
+ modify it under the terms of the GNU General Public License as
+ published by the Free Software Foundation; either version 2 of the
+ License, or (at your option) any later version.
+
+ This program is distributed in the hope that it will be useful, but
+ WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ General Public License for more details.
+-->
+<PropertyList>
+  <params>
+    <from>environment/metar/clouds/layer[0]/elevation-ft</from>
+    <to>/environment/clouds/layer[0]/elevation-ft</to>
+  </params>
+  <name>MetarController:clouds:altitude_set</name>
+  <type>gain</type>
+  <gain>1.0</gain>
+  <enable>
+    <condition>
+      <property>/environment/metar/valid</property>
+      <or>
+        <less-than>
+          <property alias="../../../../../params/from"/>
+          <value>-9000</value>
+        </less-than>
+        <less-than>
+          <property alias="../../../../../params/to"/>
+          <value>-9000</value>
+        </less-than>
+      </or>
+    </condition>
+  </enable>
+  <input alias="../params/from"/>
+  <output alias="../params/to"/>
+</PropertyList>
diff --git a/Environment/clouds-coverage.xml b/Environment/clouds-coverage.xml
new file mode 100644
index 000000000..83e2fdbbe
--- /dev/null
+++ b/Environment/clouds-coverage.xml
@@ -0,0 +1,37 @@
+<?xml version="1.0" ?>
+<!--
+ This file is part of FlightGear, the free flight simulator
+ http://www.flightgear.org/
+
+ Copyright (C) 2009 Torsten Dreyer, Torsten (at) t3r _dot_ de
+
+ This program is free software; you can redistribute it and/or
+ modify it under the terms of the GNU General Public License as
+ published by the Free Software Foundation; either version 2 of the
+ License, or (at your option) any later version.
+
+ This program is distributed in the hope that it will be useful, but
+ WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ General Public License for more details.
+-->
+<PropertyList>
+  <params>
+    <from>/environment/metar/clouds/layer[0]/coverage-type</from>
+    <to>environment/clouds/layer[0]/coverage-type</to>
+  </params>
+  <name>MetarController:clouds:coverage</name>
+  <type>gain</type>
+  <gain>1.0</gain>
+  <enable>
+    <condition>
+      <property>/environment/metar/valid</property>
+      <not-equals>
+        <property alias="../../../../params/from"/>
+        <property alias="../../../../params/to"/>
+      </not-equals>
+    </condition>
+  </enable>
+  <input alias="../params/from"/>
+  <output alias="../params/to"/>
+</PropertyList>
diff --git a/Environment/clouds-thickness.xml b/Environment/clouds-thickness.xml
new file mode 100644
index 000000000..89e64573a
--- /dev/null
+++ b/Environment/clouds-thickness.xml
@@ -0,0 +1,29 @@
+<?xml version="1.0" ?>
+<!--
+ This file is part of FlightGear, the free flight simulator
+ http://www.flightgear.org/
+
+ Copyright (C) 2009 Torsten Dreyer, Torsten (at) t3r _dot_ de
+
+ This program is free software; you can redistribute it and/or
+ modify it under the terms of the GNU General Public License as
+ published by the Free Software Foundation; either version 2 of the
+ License, or (at your option) any later version.
+
+ This program is distributed in the hope that it will be useful, but
+ WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ General Public License for more details.
+-->
+<PropertyList>
+  <name>MetarController:clouds:thickness</name>
+  <enable>
+    <condition>
+      <property>/environment/metar/valid</property>
+    </condition>
+  </enable>
+  <input>/environment/metar/clouds/layer[0]/thickness-ft</input>
+  <output>/environment/clouds/layer[0]/thickness-ft</output>
+  <type>noise-spike</type>
+  <max-rate-of-change>8.3333</max-rate-of-change>
+</PropertyList>
diff --git a/Environment/environment.xml b/Environment/environment.xml
index d20eda081..71e44e61e 100644
--- a/Environment/environment.xml
+++ b/Environment/environment.xml
@@ -43,7 +43,7 @@
     </scenario>
     <scenario>
       <name>Stormy Monday</name>
-      <metar>XXXX 012345Z 28035G50KT 9999 TSRA SCT022CB BKN030 13/09 Q1005</metar>
+      <metar>XXXX 012345Z 28035G50KT 250V300 9999 TSRA SCT022CB BKN030 13/09 Q1005</metar>
       <description>You're out for an adventure? Gusty winds blowing from the west
                    and isolated thunderstorms should be avoided. Fasten your seatbelt!</description>
     </scenario>
@@ -169,31 +169,33 @@
   </config>
 
   <clouds>
-   <status>true</status>
    <layer n="0">
     <coverage>clear</coverage>
-    <elevation-ft>4000</elevation-ft>
+    <elevation-ft>-9999</elevation-ft>
     <thickness-ft>600</thickness-ft>
     <transition-ft>150</transition-ft>
     <span-m>40000</span-m>
    </layer>
    <layer n="1">
     <coverage>clear</coverage>
-    <elevation-ft>19500</elevation-ft>
+    <elevation-ft>-9999</elevation-ft>
     <thickness-ft>65</thickness-ft>
     <transition-ft>25</transition-ft>
     <span-m>40000</span-m>
    </layer>
    <layer n="2">
     <coverage>clear</coverage>
+    <elevation-ft>-9999</elevation-ft>
     <span-m>40000</span-m>
    </layer>
    <layer n="3">
     <coverage>clear</coverage>
+    <elevation-ft>-9999</elevation-ft>
     <span-m>40000</span-m>
    </layer>
-   <layer n="5">
+   <layer n="4">
     <coverage>clear</coverage>
+    <elevation-ft>-9999</elevation-ft>
     <span-m>40000</span-m>
    </layer>
   </clouds>
diff --git a/Environment/interpolator.xml b/Environment/interpolator.xml
new file mode 100644
index 000000000..761bb608c
--- /dev/null
+++ b/Environment/interpolator.xml
@@ -0,0 +1,111 @@
+<?xml version="1.0" ?>
+<!--
+ This file is part of FlightGear, the free flight simulator
+ http://www.flightgear.org/
+
+ Copyright (C) 2009 Torsten Dreyer, Torsten (at) t3r _dot_ de
+
+ This program is free software; you can redistribute it and/or
+ modify it under the terms of the GNU General Public License as
+ published by the Free Software Foundation; either version 2 of the
+ License, or (at your option) any later version.
+
+ This program is distributed in the hope that it will be useful, but
+ WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ General Public License for more details.
+-->
+<!--
+  Interpolate the values of /environment/interpolated/* over time
+  and write the results to /environment/*, the environment of our
+  aircraft
+  All filters are enabled on /environment/config/enabled=true
+-->
+<PropertyList>
+  
+  <filter>
+    <name>EnvironmentInterpolator:temperature-sea-level-degc</name>
+    <enable>
+      <condition>
+        <property>/environment/config/enabled</property>
+      </condition>
+    </enable>
+    <input>/environment/config/interpolated/temperature-sea-level-degc</input>
+    <output>/environment/temperature-sea-level-degc</output>
+    <type>noise-spike</type>
+    <max-rate-of-change>0.1667</max-rate-of-change>
+  </filter>
+  
+  <filter>
+    <name>EnvironmentInterpolator:dewpoint-sea-level-degc</name>
+    <enable>
+      <condition>
+        <property>/environment/config/enabled</property>
+      </condition>
+    </enable>
+    <input>/environment/config/interpolated/dewpoint-sea-level-degc</input>
+    <output>/environment/dewpoint-sea-level-degc</output>
+    <type>noise-spike</type>
+    <max-rate-of-change>0.1667</max-rate-of-change>
+  </filter>
+  
+  <filter>
+    <!--
+      transfer the interpolated QNH to the global environment
+      limit the rate of change to approx 1hpa/sec
+    -->
+    <name>EnvironmentInterpolator:pressure-sea-level-inhg</name>
+    <type>noise-spike</type>
+    <max-rate-of-change>0.03</max-rate-of-change>
+    <enable>
+      <condition>
+        <property>/environment/config/enabled</property>
+      </condition>
+    </enable>
+    <input>/environment/config/interpolated/pressure-sea-level-inhg</input>
+    <output>/environment/pressure-sea-level-inhg</output>
+  </filter>
+
+  <filter>
+    <name>EnvironmentInterpolator:visibility-m</name>
+    <enable>
+      <condition>
+        <property>/environment/config/enabled</property>
+      </condition>
+    </enable>
+    <input>/environment/config/interpolated/visibility-m</input>
+    <output>/environment/visibility-m</output>
+    <type>exponential</type>
+    <filter-time>10</filter-time>
+  </filter>
+
+  <!-- 
+    filter the wind vector by filtering the cartesian representation
+  -->
+  <filter>
+    <name>EnvironmentInterpolator:wind-from-north</name>
+    <enable>
+      <condition>
+        <property>/environment/config/enabled</property>
+      </condition>
+    </enable>
+    <input>/environment/config/interpolated/wind-from-north-fps</input>
+    <output>/environment/wind-from-north-fps</output>
+    <type>exponential</type>
+    <filter-time>5</filter-time>
+  </filter>
+
+  <filter>
+    <name>EnvironmentInterpolator:wind-from-east</name>
+    <enable>
+      <condition>
+        <property>/environment/config/enabled</property>
+      </condition>
+    </enable>
+    <input>/environment/config/interpolated/wind-from-east-fps</input>
+    <output>/environment/wind-from-east-fps</output>
+    <type>exponential</type>
+    <filter-time>5</filter-time>
+  </filter>
+
+</PropertyList>
diff --git a/Environment/layer-heading-offset.xml b/Environment/layer-heading-offset.xml
new file mode 100644
index 000000000..363f71560
--- /dev/null
+++ b/Environment/layer-heading-offset.xml
@@ -0,0 +1,36 @@
+<?xml version="1.0" ?>
+<!--
+ This file is part of FlightGear, the free flight simulator
+ http://www.flightgear.org/
+
+ Copyright (C) 2009 Torsten Dreyer, Torsten (at) t3r _dot_ de
+
+ This program is free software; you can redistribute it and/or
+ modify it under the terms of the GNU General Public License as
+ published by the Free Software Foundation; either version 2 of the
+ License, or (at your option) any later version.
+
+ This program is distributed in the hope that it will be useful, but
+ WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ General Public License for more details.
+-->
+<PropertyList>
+  <name>MetarController:layer:wind-from-heading-deg</name>
+  <type>gain</type>
+  <gain>1.0</gain>
+  <enable>
+    <condition>
+      <property>/environment/metar/valid</property>
+    </condition>
+  </enable>
+  <input>
+    <property>/environment/config/boundary/entry[0]/wind-from-heading-deg</property>
+    <offset>/environment/config/boundary/entry[1]/wind-heading-change-deg</offset>
+  </input>
+  <output>/environment/config/boundary/entry[1]/wind-from-heading-deg</output>
+  <period>
+    <min>0</min>
+    <max>360</max>
+  </period>
+</PropertyList>
diff --git a/Environment/layer-speed-change.xml b/Environment/layer-speed-change.xml
new file mode 100644
index 000000000..6cce732f4
--- /dev/null
+++ b/Environment/layer-speed-change.xml
@@ -0,0 +1,39 @@
+<?xml version="1.0" ?>
+<!--
+ This file is part of FlightGear, the free flight simulator
+ http://www.flightgear.org/
+
+ Copyright (C) 2009 Torsten Dreyer, Torsten (at) t3r _dot_ de
+
+ This program is free software; you can redistribute it and/or
+ modify it under the terms of the GNU General Public License as
+ published by the Free Software Foundation; either version 2 of the
+ License, or (at your option) any later version.
+
+ This program is distributed in the hope that it will be useful, but
+ WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ General Public License for more details.
+-->
+<PropertyList>
+  <name>MetarController:layer:wind-speed-kt</name>
+  <type>gain</type>
+  <gain>1.0</gain>
+  <enable>
+    <condition>
+      <property>/environment/metar/valid</property>
+    </condition>
+  </enable>
+  <input>
+    <expression>
+      <product>
+        <property>/environment/config/boundary/entry[0]/wind-speed-kt</property>
+        <sum>
+          <property>/environment/config/boundary/entry[1]/wind-speed-change-rel</property>
+          <value>1.0</value>
+        </sum>
+      </product>
+    </expression>
+  </input>
+  <output>/environment/config/boundary/entry[1]/wind-speed-kt</output>
+</PropertyList>
diff --git a/Environment/metarinterpolator.xml b/Environment/metarinterpolator.xml
new file mode 100644
index 000000000..35775635f
--- /dev/null
+++ b/Environment/metarinterpolator.xml
@@ -0,0 +1,375 @@
+<?xml version="1.0" ?>
+<!--
+ This file is part of FlightGear, the free flight simulator
+ http://www.flightgear.org/
+
+ Copyright (C) 2009 Torsten Dreyer, Torsten (at) t3r _dot_ de
+
+ This program is free software; you can redistribute it and/or
+ modify it under the terms of the GNU General Public License as
+ published by the Free Software Foundation; either version 2 of the
+ License, or (at your option) any later version.
+
+ This program is distributed in the hope that it will be useful, but
+ WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ General Public License for more details.
+-->
+<!--
+  Interpolate the METAR weather values over time and write
+  the environment values in /environment/config/*
+  All filters are enabled if /environment/metar/valid=true
+  -->
+<PropertyList> 
+  <filter>
+    <!-- 
+      transfer the METAR QNH to the interpolation controller
+      limit the rate of change to approx 0.01hpa/sec
+    -->
+    <name>MetarController:pressure-sea-level-inhg</name>
+    <type>noise-spike</type>
+    <max-rate-of-change>0.0003</max-rate-of-change>
+    <enable>
+      <condition>
+        <property>/environment/metar/valid</property>
+      </condition>
+    </enable>
+    <input>/environment/metar/pressure-sea-level-inhg</input>
+    <output>/environment/config/boundary/entry/pressure-sea-level-inhg</output>
+    <output>/environment/config/aloft/entry/pressure-sea-level-inhg</output>
+  </filter>
+
+  <filter>
+    <!-- 
+      transfer the sea-level temperature to each layer of
+      interpolation controller. We have no idea here about
+      the temperature gradient, so just assume ISA.
+    -->
+    <name>MetarController:temperature-sea-level-degc</name>
+    <type>noise-spike</type>
+    <max-rate-of-change>0.01667</max-rate-of-change>
+    <enable>
+      <condition>
+        <property>/environment/metar/valid</property>
+      </condition>
+    </enable>
+    <input>/environment/metar/temperature-sea-level-degc</input>
+    <output>/environment/config/boundary/entry[0]/temperature-sea-level-degc</output>
+    <output>/environment/config/boundary/entry[1]/temperature-sea-level-degc</output>
+    <output>/environment/config/aloft/entry[0]/temperature-sea-level-degc</output>
+    <output>/environment/config/aloft/entry[1]/temperature-sea-level-degc</output>
+    <output>/environment/config/aloft/entry[2]/temperature-sea-level-degc</output>
+    <output>/environment/config/aloft/entry[3]/temperature-sea-level-degc</output>
+    <output>/environment/config/aloft/entry[4]/temperature-sea-level-degc</output>
+  </filter>
+
+  <filter>
+    <!--
+      transfer the sea-level temperature to each layer of
+      interpolation controller. 
+    -->
+    <name>MetarController:dewpoint-sea-level-degc</name>
+    <type>noise-spike</type>
+    <max-rate-of-change>0.01667</max-rate-of-change>
+    <enable>
+      <condition>
+        <property>/environment/metar/valid</property>
+      </condition>
+    </enable>
+    <input>/environment/metar/dewpoint-sea-level-degc</input>
+    <output>/environment/config/boundary/entry[0]/dewpoint-sea-level-degc</output>
+    <output>/environment/config/boundary/entry[1]/dewpoint-sea-level-degc</output>
+    <output>/environment/config/aloft/entry[0]/dewpoint-sea-level-degc</output>
+    <output>/environment/config/aloft/entry[1]/dewpoint-sea-level-degc</output>
+    <output>/environment/config/aloft/entry[2]/dewpoint-sea-level-degc</output>
+    <output>/environment/config/aloft/entry[3]/dewpoint-sea-level-degc</output>
+    <output>/environment/config/aloft/entry[4]/dewpoint-sea-level-degc</output>
+  </filter>
+
+  <filter>
+    <!--
+      transfer the sea-level temperature to each layer of
+      interpolation controller. We are not very creative here and 
+      use the same visibility for all layers but top three which
+      are left untouched.
+    -->
+    <name>MetarController:visibility-m</name>
+    <type>exponential</type>
+    <filter-time>30</filter-time>
+    <enable>
+      <condition>
+        <property>/environment/metar/valid</property>
+      </condition>
+    </enable>
+    <input>/environment/metar/min-visibility-m</input>
+    <output>/environment/config/boundary/entry[0]/visibility-m</output>
+    <output>/environment/config/boundary/entry[1]/visibility-m</output>
+    <output>/environment/config/aloft/entry[0]/visibility-m</output>
+    <output>/environment/config/aloft/entry[1]/visibility-m</output>
+  </filter>
+
+  <!-- split the wind vector into it's components -->
+
+  <filter>
+    <name>MetarController:wind-from-north-kt</name>
+    <type>exponential</type>
+    <filter-time>30</filter-time>
+    <enable>
+      <condition>
+        <property>/environment/metar/valid</property>
+      </condition>
+    </enable>
+    <input>
+      <expression>
+        <cos>
+          <product>
+            <property>/environment/metar/base-wind-dir-deg</property>
+            <value>0.0174533</value>
+          </product>
+        </cos>
+      </expression>
+      <scale>/environment/metar/base-wind-speed-kt</scale>
+    </input>
+    <output>/environment/metar/base-wind-from-north-kt</output>
+  </filter>
+
+  <filter>
+    <name>MetarController:wind-from-east-kt</name>
+    <type>exponential</type>
+    <filter-time>30</filter-time>
+    <enable>
+      <condition>
+        <property>/environment/metar/valid</property>
+      </condition>
+    </enable>
+    <input>
+      <expression>
+        <sin>
+          <product>
+            <property>/environment/metar/base-wind-dir-deg</property>
+            <value>0.0174533</value>
+          </product>
+        </sin>
+      </expression>
+      <scale>/environment/metar/base-wind-speed-kt</scale>
+    </input>
+    <output>/environment/metar/base-wind-from-east-kt</output>
+  </filter>
+
+  <filter>
+    <name>MetarController::wind-speed-kt</name>
+    <enable>
+      <condition>
+        <property>/environment/metar/valid</property>
+      </condition>
+    </enable>
+    <input>
+      <expression>
+        <!-- pythagoras in markup language -->
+        <sqrt>
+          <sum>
+            <product>
+              <property>/environment/metar/base-wind-from-east-kt</property>
+              <property>/environment/metar/base-wind-from-east-kt</property>
+            </product>
+            <product>
+              <property>/environment/metar/base-wind-from-north-kt</property>
+              <property>/environment/metar/base-wind-from-north-kt</property>
+            </product>
+          </sum>
+        </sqrt>
+      </expression>
+    </input>
+    <output>/environment/config/boundary/entry[0]/wind-speed-kt</output>
+    <type>gain</type>
+    <gain>1.0</gain>
+  </filter>
+
+  <filter>
+    <name>MetarController:wind-from-heading-deg</name>
+    <enable>
+      <condition>
+        <property>/environment/metar/valid</property>
+      </condition>
+    </enable>
+    <input>
+      <expression>
+        <atan2>
+          <property>/environment/metar/base-wind-from-east-kt</property>
+          <property>/environment/metar/base-wind-from-north-kt</property>
+        </atan2>
+      </expression>
+    </input>
+    <output>/environment/config/boundary/entry[0]/wind-from-heading-deg</output>
+    <type>gain</type>
+    <gain>57.3</gain> <!-- radians to degree -->
+    <period>
+      <min>0</min>
+      <max>360</max>
+    </period>
+  </filter>
+
+  <!-- Adjust the wind-vector for the layers -->
+  <!-- TODO: handle variable winds -->
+  <filter include="layer-heading-offset.xml"/>
+  <filter include="layer-heading-offset.xml">
+    <input>
+      <offset>/environment/config/aloft/entry[0]/wind-heading-change-deg</offset>
+    </input>
+    <output>/environment/config/aloft/entry[0]/wind-from-heading-deg</output>
+  </filter>
+  <filter include="layer-heading-offset.xml">
+    <input>
+      <offset>/environment/config/aloft/entry[1]/wind-heading-change-deg</offset>
+    </input>
+    <output>/environment/config/aloft/entry[1]/wind-from-heading-deg</output>
+  </filter>
+  <filter include="layer-heading-offset.xml">
+    <input>
+      <offset>/environment/config/aloft/entry[2]/wind-heading-change-deg</offset>
+    </input>
+    <output>/environment/config/aloft/entry[2]/wind-from-heading-deg</output>
+  </filter>
+  <filter include="layer-heading-offset.xml">
+    <input>
+      <offset>/environment/config/aloft/entry[3]/wind-heading-change-deg</offset>
+    </input>
+    <output>/environment/config/aloft/entry[3]/wind-from-heading-deg</output>
+  </filter>
+  <filter include="layer-heading-offset.xml">
+    <input>
+      <offset>/environment/config/aloft/entry[4]/wind-heading-change-deg</offset>
+    </input>
+    <output>/environment/config/aloft/entry[4]/wind-from-heading-deg</output>
+  </filter>
+
+  <filter include="layer-speed-change.xml"/>
+  <filter include="layer-speed-change.xml">
+    <input>
+      <offset>/environment/config/aloft/entry[0]/wind-speed-change-rel</offset>
+    </input>
+    <output>/environment/config/aloft/entry[0]/wind-speed-kt</output>
+  </filter>
+  <filter include="layer-speed-change.xml">
+    <input>
+      <offset>/environment/config/aloft/entry[1]/wind-speed-change-rel</offset>
+    </input>
+    <output>/environment/config/aloft/entry[1]/wind-speed-kt</output>
+  </filter>
+  <filter include="layer-speed-change.xml">
+    <input>
+      <offset>/environment/config/aloft/entry[2]/wind-speed-change-rel</offset>
+    </input>
+    <output>/environment/config/aloft/entry[2]/wind-speed-kt</output>
+  </filter>
+  <filter include="layer-speed-change.xml">
+    <input>
+      <offset>/environment/config/aloft/entry[3]/wind-speed-change-rel</offset>
+    </input>
+    <output>/environment/config/aloft/entry[3]/wind-speed-kt</output>
+  </filter>
+  <filter include="layer-speed-change.xml">
+    <input>
+      <offset>/environment/config/aloft/entry[4]/wind-speed-change-rel</offset>
+    </input>
+    <output>/environment/config/aloft/entry[4]/wind-speed-kt</output>
+  </filter>
+
+  <!-- Clouds -->
+  <!-- don't interpolate to/from altitude -9999 -->
+  <filter include="clouds-altitude-set.xml"/>
+  <filter include="clouds-altitude-set.xml">
+    <params>
+      <from>/environment/metar/clouds/layer[1]/elevation-ft</from>
+      <to>/environment/clouds/layer[1]/elevation-ft</to>
+    </params>
+  </filter>
+  <filter include="clouds-altitude-set.xml">
+    <params>
+      <from>/environment/metar/clouds/layer[2]/elevation-ft</from>
+      <to>/environment/clouds/layer[2]/elevation-ft</to>
+    </params>
+  </filter>
+  <filter include="clouds-altitude-set.xml">
+    <params>
+      <from>/environment/metar/clouds/layer[3]/elevation-ft</from>
+      <to>/environment/clouds/layer[3]/elevation-ft</to>
+    </params>
+  </filter>
+  <filter include="clouds-altitude-set.xml">
+    <params>
+      <from>/environment/metar/clouds/layer[4]/elevation-ft</from>
+      <to>/environment/clouds/layer[4]/elevation-ft</to>
+    </params>
+  </filter>
+
+  <filter include="clouds-altitude-interpolate.xml"/>
+  <filter include="clouds-altitude-interpolate.xml">
+    <params>
+      <from>/environment/metar/clouds/layer[1]/elevation-ft</from>
+      <to>/environment/clouds/layer[1]/elevation-ft</to>
+    </params>
+  </filter>
+  <filter include="clouds-altitude-interpolate.xml">
+    <params>
+      <from>/environment/metar/clouds/layer[2]/elevation-ft</from>
+      <to>/environment/clouds/layer[2]/elevation-ft</to>
+    </params>
+  </filter>
+  <filter include="clouds-altitude-interpolate.xml">
+    <params>
+      <from>/environment/metar/clouds/layer[3]/elevation-ft</from>
+      <to>/environment/clouds/layer[3]/elevation-ft</to>
+    </params>
+  </filter>
+  <filter include="clouds-altitude-interpolate.xml">
+    <params>
+      <from>/environment/metar/clouds/layer[4]/elevation-ft</from>
+      <to>/environment/clouds/layer[4]/elevation-ft</to>
+    </params>
+  </filter>
+
+  <filter include="clouds-thickness.xml"/>
+  <filter include="clouds-thickness.xml">
+    <input>/environment/metar/clouds/layer[1]/thickness-ft</input>
+    <output>/environment/clouds/layer[1]/thickness-ft</output>
+  </filter>
+  <filter include="clouds-thickness.xml">
+    <input>/environment/metar/clouds/layer[2]/thickness-ft</input>
+    <output>/environment/clouds/layer[2]/thickness-ft</output>
+  </filter>
+  <filter include="clouds-thickness.xml">
+    <input>/environment/metar/clouds/layer[3]/thickness-ft</input>
+    <output>/environment/clouds/layer[3]/thickness-ft</output>
+  </filter>
+  <filter include="clouds-thickness.xml">
+    <input>/environment/metar/clouds/layer[4]/thickness-ft</input>
+    <output>/environment/clouds/layer[4]/thickness-ft</output>
+  </filter>
+
+  <filter include="clouds-coverage.xml"/>
+  <filter include="clouds-coverage.xml">
+    <params>
+      <from>/environment/metar/clouds/layer[1]/coverage-type</from>
+      <to>environment/clouds/layer[1]/coverage-type</to>
+    </params>
+  </filter>
+  <filter include="clouds-coverage.xml">
+    <params>
+      <from>/environment/metar/clouds/layer[2]/coverage-type</from>
+      <to>environment/clouds/layer[2]/coverage-type</to>
+    </params>
+  </filter>
+  <filter include="clouds-coverage.xml">
+    <params>
+      <from>/environment/metar/clouds/layer[3]/coverage-type</from>
+      <to>environment/clouds/layer[3]/coverage-type</to>
+    </params>
+  </filter>
+  <filter include="clouds-coverage.xml">
+    <params>
+      <from>/environment/metar/clouds/layer[4]/coverage-type</from>
+      <to>environment/clouds/layer[4]/coverage-type</to>
+    </params>
+  </filter>
+</PropertyList>