HDD 

Heating degree days. HDD is calculated as the number of degrees a mean daily temperature is below a value (specified as the Temperature element), for each day. For example, if the mean temperature in a region drops to 64 degrees for four days during a year, the rest of the time staying above 65, and the Temperature element is set at 65, then HDD = 4.

Element Information

Model

Temperature | HDDValue
Children: HDDValue, Temperature

Used By

Element Weather

Source 

<xsd:element name="HDD">
  <xsd:annotation>
    <xsd:documentation>Heating degree days. HDD is calculated as the number of degrees a mean daily temperature is below a value (specified as the Temperature element), for each day. For example, if the mean temperature in a region drops to 64 degrees for four days during a year, the rest of the time staying above 65, and the Temperature element is set at 65, then HDD = 4.</xsd:documentation>
  </xsd:annotation>
  <xsd:complexType>
    <xsd:choice minOccurs="0" maxOccurs="unbounded">
      <xsd:element ref="Temperature"/>
      <xsd:element ref="HDDValue"/>
    </xsd:choice>
  </xsd:complexType>
</xsd:element>

Sample