<xs:simpleType name="cloudTypeAnnex3Type">
  <xs:annotation>
    <xs:documentation>
      <html:div xmlns="http://www.w3.org/1999/xhtml">
        <p>From the ICAO's "Annex 3 to the Convention on International Civil Aviation: Meteorological Service for International Air Navigation", Appendix 1, page 16.</p>
        <dl>
          <dt>CI</dt>
          <dd>Cirrus</dd>
          <dt>CC</dt>
          <dd>Cirrocumulus</dd>
          <dt>CS</dt>
          <dd>Cirrostratus</dd>
          <dt>AC</dt>
          <dd>Altocumulus</dd>
          <dt>AS</dt>
          <dd>Altostratus</dd>
          <dt>NS</dt>
          <dd>Nimbostratus</dd>
          <dt>SC</dt>
          <dd>Stratocumulus</dd>
          <dt>ST</dt>
          <dd>Stratus</dd>
          <dt>CU</dt>
          <dd>Cumulus</dd>
          <dt>CB</dt>
          <dd>Cumulonimbus</dd>
          <dt>UNKNOWN</dt>
          <dd>Unknown type</dd>
        </dl>
      </html:div>
    </xs:documentation>
  </xs:annotation>
  <xs:restriction base="xs:string">
    <xs:enumeration value="CI"/>
    <xs:enumeration value="CC"/>
    <xs:enumeration value="CS"/>
    <xs:enumeration value="AC"/>
    <xs:enumeration value="AS"/>
    <xs:enumeration value="NS"/>
    <xs:enumeration value="SC"/>
    <xs:enumeration value="ST"/>
    <xs:enumeration value="CU"/>
    <xs:enumeration value="CB"/>
    <xs:enumeration value="UNKNOWN"/>
  </xs:restriction>
</xs:simpleType>