weather-CurrentConditions

Each WeatherReport component has a Current Conditions child component that contains a number of read-only status properties for up-to-date weather statistics, as well as sunrise and sunset times (Figure 10).

Figure 10. Current Conditions (property sheet)

An iconic summary is also available, on the parent WeatherReport’s default Current Weather View.

Starting in AX-3.6, a child “Advisories” container provides management of received weather advisories, for use in the station’s alarming subsystem, and an air quality view is also available. For related details, see AdvisoryContainer and Current Air Quality View.

CurrentConditions properties

The following properties are included under CurrentConditions:

Status

Typically “ok” if a connection was made. Other possible statuses include:
- alarm — if a hazardous condition is imminent/detected in an NWS provider-issued advisory. If alarm, related information is also in properties Weather Summary and State.
- fault — if the weather provider references an invalid weather station.
- stale — if a weather update connection fails, or (starting in AX-3.7) for a NwsWeatherProvider, if the reported observation time (“Observation” property) is more than 2 hours in the past. All other properties with status (Sundown, Temp, State, Humidity, and so on) also assume this stale status. Prior to AX-3.7, the timeout for this “failed connection at update attempt” to a NWS provider is fixed at 15 seconds.
Last Update

Date/timestamp of the station’s last weather report update, in Baja AbsTime format.
Observed

(AX-3.7 and later only) Date/timestamp of when the NWS reported the observed values in the last update, in Baja AbsTime format.
Sunrise

Timestamp for sunrise, in Baja Time format.
Sunset

Timestamp for sunset, in Baja Time format.
Sundown

StatusBoolean value that is “true” when the sun is down, else “false” when the sun is up. This dynamically updates whenever current time matches the “Sunrise” and “Sunset” times.
Temp

Current temperature as a StatusNumeric value.
Weather Summary

Text descriptor summarizing current weather conditions, as a StatusString value. This text string is evaluated and converted to a “State” enumerated value (next property). If CurrentConditions has an “alarm” status, this will describe the alarm condition.
State

StatusEnum value derived from the received “weather summary” text. Starting in AX-3.5, enumerations were added for hazardous conditions, such as received in provider-issued advisories. For more details, see the next section State.
Humidity

Current humidity as a StatusNumeric value.
Wind Direction

StatusEnum value derived from received text. For more details, see the section Wind Direction.
Wind Speed

Current wind speed value, as a StatusNumeric.
Wind Gust

Reported wind gust speed (if available), as a StatusNumeric. Possibly “null” if not available.
Wind Chill

This is calculated by Niagara using a NOAA formula, providing that the:
- temperature is between -50 and 50 degrees F, and
- wind speed is between 3 and 110 mph (and is specific to the NWS provider).
Otherwise, this value is “null”. Note that humidity is also utilized. Currently, this formula is at:
```
http://www.nws.noaa.gov/om/windchill/index.shtml
```
Pressure

Current barometric pressure, as a StatusNumeric value.
Dew Point

Current dew point reading, as a StatusNumeric value.
Heat Index

This is calculated by Niagara using a NOAA formula, providing that the:
- temperature > 80 degrees F, and
- dew point > 60 degrees F, and
- humidity > 40% (and is specific to the NWS provider).
Otherwise, this value is “null”. Currently, this formula is at:
```
http://www.nws.noaa.gov/jkl/?n=heat_index_calculator
```
Visibility

Current visibility distance value, as a StatusNumeric value.
Ozone

(AX-3.6 and later) Level of ozone in the air, in parts per million (ppm), as a StatusNumeric value.
Particulate Matter

(AX-3.6 and later) Level of particulate matter in the air, in micrograms per cubic meter (ug/m^3), as a StatusNumeric value.

Related to these last two properties, the CurrentConditions component also has a “Current Air Quality View”. See Current Air Quality View.
The WeatherService retrieves air quality metrics by connecting to a U.S. EPA (Environmental Protection Agency) server. For more details, see About EPA connections.

About weather State

The State value of CurrentConditions and any Forecast component is a status enumeration derived from received weather summary text, using a best effort approach.

This summary text appears in the CurrentConditions property sheet as the “Weather Summary” value.

You can link from the State slot of CurrentConditions or a Forecast component to a StatusEnum type slot of a control point, if needed. Facets of a linked point should be set to the frozen range (EnumRange) of “WeatherState” in the weather module to capture all 28 possible states (see Figure 11).

Figure 11. WeatherState enumerations seen in Facets, range Enum dialog

Starting in AX-3.5, some enumerations were added for hazardous weather conditions, as received in provider-issued watches, warnings, and advisories—for example: tsunami, tornado, flood, and so on. These are reflected in the State property of CurrentConditions only if its Status is “alarm”. For related details, see NwsAdvisoryAlarmExt.

About weather Wind Direction

The Wind Direction value of CurrentConditions is a status enumeration derived from received text. You can link from the Wind Direction slot to a StatusEnum type slot of a control point, if needed. Facets of a linked point should be set to the frozen range (EnumRange) of “WindDirection” in the weather module to capture all 8 possible states (see Figure 12).

Figure 12. WindDirection enumerations seen in Facets, range Enum dialog