: Public Class
Created: 23/05/2012 12:49:11 PM
Modified: 27/09/2013 4:22:19 PM
Project:
Advanced:
A specialized Record type containing meteorological conditions forecast at an aerodrome.  This class is also related but not identical to MeteorologicalAerodromeTrendForecastRecord, which is reported on a METAR/SPECI - conditions reported in trend forecasts in METAR/SPECI differ from forecast groups in a TAF.<br /></p><p><br /></p><p>When no clouds of operational significance or no weather of operational significance is predicted, the nothingOfOperationalSignificance nilReason should be used for the cloud or presentWeather association.  <br /></p><p><br /></p><p>Note that the TAC representations for "FM", "TL", and "AT" are represented by the phenomenonTime on the change forecast (MeteorologicalAerodromeForecast):<br /></p><p>    FM and TL - a phenomenonTime with a TimePeriod (start is FM and end is TL)<br /></p><p>    TL - a phenomenonTime with a TimePeriod (start is beginning of forecast validity and end is TL)<br /></p><p>    FM - a phenomenonTime with a TimePeriod (start is FM and end is end of forecast validity)<br /></p><p>    AT - a phenomenonTime with a TimeInstant<br /></p>
Attribute
Public AerodromeForecastChangeIndicator
  changeIndicator

Details:
sequenceNumber=1
xsdAsAttribute=true
Notes: The type of change being reported (FROM, BECOMING,  TEMPORARY, etc.).<br /></p><p><br /></p><p>A change indicator is required for all MeteorologicalAerodromeForecastRecords excepting reported base conditions.<br /></p>
Public Boolean
  cloudAndVisibilityOK

Details:
sequenceNumber=2
xsdAsAttribute=true
Notes: When true, indicates that the observed cloud ceiling, horizontal visibility, and weather conditions are of no operational significance.  See ICAO Annex 3 / WMO No. 49-2 Section 2.2. Also known as "CAVOK"<br /></p><p><br /></p><p>When CAVOK conditions are observed, no other information on visibility, runway visual range, present weather, cloud amount, or cloud type is reported<br /></p>
Public Distance
  prevailingVisibility

Details:
quantity=http://codes.wmo.int/common/quantity-kind/aeronauticalPrevailingHorizontalVisibility
sequenceNumber=4
Notes: The prevailing horizontal visibility, mandatory except when ceiling and visibility is reported as OK
Public RelationalOperator
  prevailingVisibilityOperator

Details:
Notes: The reported relational operator for the prevailing horizontal visibility.  When reported, this operator is reported in conjunction with prevailing visibility.<br /></p><p><br /></p><p>To report a prevailing visibility of at least 10000 meters, prevailing visibility is reported as 10000 meters and the operator is reported as "above".  <br /></p><p><br /></p><p>When no operator is reported, prevailing visibility represents an exact value with identical semantics to other measured quantities<br /></p>
Element Source Role Target Role
«DataType» AerodromeAirTemperatureForecast
Class  
Name:  
 
Name: temperature
 
Details:
Minimum and maximum temperatures observed at specific times, consisting of up to a maximum of four temperatures (two maximum temperatures and two minimum temperatures).<br /></p><p><br /></p><p>Due to Note 9 on Table A5-1: "consisting of up to a maximum of four temperatures (two maximum temperatures and two minimum temperatures)", there can be up to two temperature groups on each MeteorologicalAerodromeForecastRecord.  It is possible that Annex 3 instead specifies four temperatures for the entire TAF but no more than one for each Record, in which case this association would need to be corrected to be 0..1 and a constraint on TAF would need to be put in place to ensure that no more than two temperature forecast groups exist on any single TAF.<br /></p>
«CodeList» AerodromeForecastWeather
Class  
Name:  
 
Name: weather
 
Details:
Weather phenomenon: characteristics and type.  To be included whenever applicable.<br /></p><p><br /></p><p>One or more, up to a maximum of three weather phenomena or combinations thereof, together with their characteristics and, where appropriate, intensity, are forecast if they are expected to occur at the aerodrome<br /></p><p><br /></p><p>The expected end of occurrence of weather phenomena ("NSW") is indicated by a change forecast with a missing weather group with a nil reason of nothingOfOperationalSignificance<br /></p>
AerodromeCloudForecast
Class  
Name:  
 
Name: cloud
 
Details:
Cloud phenomenon of operational significance, including cloud type and cloud layers.  To be included whenever applicable, so as to convey a complete description of the clouds of significance to flight operations.<br /></p><p><br /></p><p>When no clouds of operational significance are forecast and “CAVOK” is not appropriate ("NSC") it should be indicated by a missing cloud group with a nil reason of nothingOfOperationalSignificance<br /></p>
AerodromeSurfaceWindForecast
Class  
Name:  
 
Name: surfaceWind
 
Details:
 
Element Source Role Target Role
«FeatureType» MeteorologicalAerodromeForecast
Class  
Name:  
 
Name: result
 
Details:
 
Constraint Type Status
if( cloudAndVisibilityOK ) prevailingVisibility == NULL Invariant Approved
Details:
 
if( cloudAndVisibilityOK ) cloud == NULL Invariant Approved
Details:
 
if( cloudAndVisibilityOK ) weather == NULL Invariant Approved
Details: