WeatherStation Objects

 

The ability add weather-dependent limits was added in Version 23

WeatherStation objects are used as part of the Weather-Dependent Limits which are accessed on the Weather-Dependent Limits dialog.

They are also used as part of the Weather Related Models and Information Dialog which can be used in conjunction with the Time Step Simulation Tool.

 

A WeatherStation object represents any location at which weather measurements are specified. The following are examples of concepts that the WeatherStation object may represent.

  1. A weather recording station

  2. The output of some special weather forecast software that you are using

  3. A National Oceanic and Atmospheric Administration (NOAA) weather station location in North America

  4. An airport where you have weather measurements

WeatherStation objects have the following input fields

Field

Type

Type

Name

String

(KEY field)

Name of the WeatherStation. This is the unique identifier (Key Field) for the WeatherStation

Enabled

Boolean

Set to YES to indicate that the WeatherStation should be used. When this is set to NO, all numeric fields for the WeatherStation will be disabled and no limit calculations can be based on this WeatherStation.

ObservationTime

String

This is the date time of when the latest observations were recorded. It is optional and when blank indicates no time is known.

Longitude

Double Float

Longitude Coordinate. An entry of blank may be given in which case there is not a valid value for this quantity. This value is stored as a double-precision floating point number and thus has about 15 significant digits instead of 7 digits for the single-precision values.

Latitude

Double Float

Latitude Coordinate. An entry of blank may be given in which case there is not a valid value for this quantity. This value is stored as a double-precision floating point number and thus has about 15 significant digits instead of 7 digits for the single-precision values.

ElevationM

ElevationFt

Single Float

Elevation of WeatherStation in meters or feet. We only store a single value internally and so the final one read will be kept. An entry of blank means there is not a valid value for this quantity.

TempF

TempC

Single Float

Temperature in Fahrenheit or Celsius. We only store a single value internally and so the final one read will be kept. An entry of blank means there is not a valid value for this quantity.

DewPointF

DewPointC

Single Float

DewPoint in Fahrenheit or Celsius. We only store a single value internally and so the final one read will be kept. An entry of blank means there is not a valid value for this quantity.

CloudCoverPerc

Single Float

Cloud Cover Percentage (between 0 and 100). An entry of blank means there is not a valid value for this quantity.

WindSpeedmph

WindSpeedKnots

WindSpeedMsec

WindSpeedkmph

Single Float

Wind Speed in miles per hour, knots, meters per second, or kilometers per hour. We only store a single value internally and so the final one read will be kept. An entry of blank means there is not a valid value for this quantity.

WindDirection

Single Float

Wind Direction in degrees. (90 = From East; 180 = From South; 270 = From West; 360 = From North. Only show 0 if wind speed also 0.)

An entry of blank means there is not a valid value for this quantity.

 

Additional fields that are calculated from other Weather Values (so they can not be edited)

Field

Type

Type

Humidity

Single Float

Humidity is calculated as ratio of exponential function of DewPoint and Temperature

WindChillF

WindChillC

Single Float

Wind Chill is calculated as a function of temperature and wind speed.

HeatIndexF

HeatIndexC

 

Single Float

Heat Index is calculated as a function of temperature and humidity

Additional fields that are calculated from latitude, longitude, time of day and other fields

Field

Type

Type

SolarElevation

Single Float

Sun Elevation (Deg). Depends on the time of day and the Latitude and Longitude of the WeatherStation

SolarAzimuth

Single Float

Sun Azimuth in compass degrees with zero due north, 90 due east, 180 due south and 270 due west. This depends on the time of day, latitude and longitude.

AtmosphericTransmittance

Single Float

Atmospheric transmittance with 1 for the sun directly overhead, and lower values as the sun goes through more of the atmosphere. This depends on the time of day, latitude and longitude.

InsolationPerc

Single Float

Estimate insolation percentage

(100-CloudCoverPerc)*AtmosphericTransmittance

 

More Optional Identifying Information for the WeatherStation

Field

Type

Type

ICAO

String

This is 4-character code assigned by the International Civil Aviation Administration. The last 3 digits are often the airport code.

GHCN

String

Global Historical Climatology Network identifier

WMO

Integer

This is 5-digit numeric code to identify a weather station assigned by the World Meteorological Organization

CountryCode

String

Two character country code; e.g., US, CA, etc.

Region

String

For the US and Canada this is the two character state or providence code

Subregion

String

County name for some US states

PlaceName

String

Extra identifier in various weather resources

StationName

String

Extra identifier in various weather resources