ladybug.epw module

class ladybug.epw.EPW(file_path)[source]

Bases: object

An EPW object containing all of the data of an .epw file.

Most of the data available in the EPW will be accessible through objects that house various properties (eg. Location). All timeseries data sets are represented as HourlyContinuousCollection objects with values and datetimes corresponding to those in the EPW file.

In order to handle the fact that EPW values run from 1:00 on Jan 1 to midnight of the following year, all timeseries data will have the ending value moved to the start of the hourly data collection upon import from the .epw file to an EPW object. This ensures that the datetimes of the data collections align with the times listed in the .epw file. This also allows the use of “true” datetimes in the hourly data collections, which start from 0:00 rather than ending with 24:00. When saving the data from a EPW object back to an .epw file, the start date time at 0:00 on Jan 1 will be moved to the end of the file, ensuring imported .epw files can be saved back to their original state without any loss of data.

The only exceptions to this movement of the last datetime are the timeseries data sets for radiation and illuminance. These data sets are left as they are when imported/exported to/from the .epw file given that they are meant to be an accumulation or average over the previous hour in the .epw file. Accordingly, such values can be thought of as an accumulation or average over the following hour when they are found within an hourly data collection of an EPW object. So the radiation with the 12:00 datetime in the hourly data collection represents the accumulated radiation in between 12:00 and 13:00.

Parameters

file_path – Local file address to an .epw file.

Properties:
  • location

  • annual_heating_design_day_996

  • annual_heating_design_day_990

  • annual_cooling_design_day_004

  • annual_cooling_design_day_010

  • heating_design_condition_dictionary

  • cooling_design_condition_dictionary

  • extreme_design_condition_dictionary

  • extreme_hot_weeks

  • extreme_cold_weeks

  • typical_weeks

  • ashrae_climate_zone

  • monthly_ground_temperature

  • header

  • years

  • dry_bulb_temperature

  • dew_point_temperature

  • relative_humidity

  • atmospheric_station_pressure

  • extraterrestrial_horizontal_radiation

  • extraterrestrial_direct_normal_radiation

  • horizontal_infrared_radiation_intensity

  • global_horizontal_radiation

  • direct_normal_radiation

  • diffuse_horizontal_radiation

  • global_horizontal_illuminance

  • direct_normal_illuminance

  • diffuse_horizontal_illuminance

  • zenith_luminance

  • wind_direction

  • wind_speed

  • total_sky_cover

  • opaque_sky_cover

  • visibility

  • ceiling_height

  • present_weather_observation

  • present_weather_codes

  • precipitable_water

  • aerosol_optical_depth

  • snow_depth

  • days_since_last_snowfall

  • albedo

  • liquid_precipitation_depth

  • liquid_precipitation_quantity

  • sky_temperature

ToString()[source]

Overwrite .NET ToString.

approximate_design_day(day_type='SummerDesignDay', percentile=0.4)[source]

Get a DesignDay object derived from percentile analysis of annual EPW data.

Note that this method is only intended to be used when there are no design days in any DDY files associated with the EPW and the EPW’s values for annual_heating_design_day or annual_cooling_design_day properties are None.

The approximated design days produced by this method tend to be less accurate than these other sources, which are usually derived from multiple years of climate data instead of only one year. Information on the error introduced by using only one year of data to create design days can be found in ASHRAE HOF 2013, Chapter 14, pg 14.

Parameters
  • day_type

    Text for the type of design day to be produced. Choose from.

    • SummerDesignDay

    • WinterDesignDay

  • percentile – A number between 0 and 50 for the percentile difference from the most extreme conditions within the EPW to be used for the design day. Typical values are 0.4 and 1.0. (Default: 0.4).

best_available_design_days(percentile=0.4)[source]

Get the best available sensible heating + cooling design days from this EPW.

This method will first check if there is a heating or cooling design day that meets the input percentile within the EPW itself. If None is found, the heating and cooling design days will be derived from analysis of the annual data within the EPW, which is usually less accurate.

Parameters

percentile – A number between 0 and 50 for the percentile difference from the most extreme conditions within the EPW to be used for the design day. Typical values are 0.4 and 1.0. (Default: 0.4).

Returns

A tuple with two design day objects. The first is the heating design day and the second is the cooling design day.

convert_to_ip()[source]

Convert all Data Collections of this EPW object to IP units.

This is useful when one knows that all graphics produced from this EPW should be in Imperial units.

convert_to_si()[source]

Convert all Data Collections of this EPW object to SI units.

This is useful when one needs to convert the EPW back to SI units from imperial units for processes like computing thermal comfort from EPW data.

classmethod from_dict(data)[source]

Create EPW from a dictionary.

Parameters

data – A python dictionary in the following format

{
"location": {} ,  # ladybug location schema
"data_collections": [],  # list of hourly annual hourly data collection
    # schemas for each of the 35 fields within the EPW file.
"metadata": {},  # dict of metadata assigned to all data collections
"heating_dict": {},  # dict containing heating design conditions
"cooling_dict": {},  # dict containing cooling design conditions
"extremes_dict": {},  # dict containing extreme design conditions
"extreme_hot_weeks": {},  # dict with values of week-long ladybug
    # analysis period schemas signifying extreme hot weeks.
"extreme_cold_weeks": {},  # dict with values of week-long ladybug
    # analysis period schemas signifying extreme cold weeks.
"typical_weeks": {},  # dict with values of week-long ladybug
    # analysis period schemas signifying typical weeks.
"monthly_ground_temps": {},  # dict with keys as floats signifying
    # depths in meters below ground and values of monthly
    # collection schema
"is_ip": False  # Boolean // denote whether the data is in IP units
"is_leap_year": False  # Boolean, denote whether data is for
                       # a leap year
"daylight_savings_start": 0,  # signify when daylight savings starts
                              # or 0 for no daylight savings
"daylight_savings_end" 0,  # signify when daylight savings ends
                           # or 0 for no daylight savings
"comments_1": ""  # String, epw comments
"comments_2": ""  # String, epw comments
}
classmethod from_file_string(file_contents)[source]

Initialize an EPW object from a string containing all EPW file contents.

This classmethod is intended for workflows where ladybug does not have access to a file system (eg. within a web browser).

Parameters

file_contents – A text string for the entirety of the EPW file contents.

classmethod from_missing_values(is_leap_year=False)[source]

Initialize an EPW object with all data missing or empty.

Note that this classmethod is intended for workflows where one plans to set all of the data within the EPW object. The EPW file written out from the use of this method is not simulate-abe or useful since all hourly data slots just possess the missing value for that data type. To obtain a EPW that is simulate-able in EnergyPlus, one must at least set the following properties:

  • location

  • dry_bulb_temperature

  • dew_point_temperature

  • relative_humidity

  • atmospheric_station_pressure

  • direct_normal_radiation

  • diffuse_horizontal_radiation

  • wind_direction

  • wind_speed

  • total_sky_cover

  • opaque_sky_cover or horizontal_infrared_radiation_intensity

Parameters

is_leap_year – A boolean to set whether the EPW object is for a leap year.

Usage:

from ladybug.epw import EPW
from ladybug.location import Location
epw = EPW.from_missing_values()
epw.location = Location('Denver Golden','CO','USA',39.74,-105.18,-7.0,1829.0)
epw.dry_bulb_temperature.values = [20] * 8760
import_data_by_field(field_number)[source]

Return an annual data collection for any field_number in epw file.

This is useful to get data for fields that the EPW object currently doesn’t have properties for (eg. Uncertainty Flags). You can find list of fields by using EPWFields.fields.

Parameters

field_number

A value between 0 to 34 for different available epw fields.

  • 0 Year

  • 1 Month

  • 2 Day

  • 3 Hour

  • 4 Minute

  • 5 Uncertainty Flags

  • 6 Dry Bulb Temperature

  • 7 Dew Point Temperature

  • 8 Relative Humidity

  • 9 Atmospheric Station Pressure

  • 10 Extraterrestrial Horizontal Radiation

  • 11 Extraterrestrial Direct Normal Radiation

  • 12 Horizontal Infrared Radiation Intensity

  • 13 Global Horizontal Radiation

  • 14 Direct Normal Radiation

  • 15 Diffuse Horizontal Radiation

  • 16 Global Horizontal Illuminance

  • 17 Direct Normal Illuminance

  • 18 Diffuse Horizontal Illuminance

  • 19 Zenith Luminance

  • 20 Wind Direction

  • 21 Wind Speed

  • 22 Total Sky Cover

  • 23 Opaque Sky Cover

  • 24 Visibility

  • 25 Ceiling Height

  • 26 Present Weather Observation

  • 27 Present Weather Codes

  • 28 Precipitable Water

  • 29 Aerosol Optical Depth

  • 30 Snow Depth

  • 31 Days Since Last Snowfall

  • 32 Albedo

  • 33 Liquid Precipitation Depth

  • 34 Liquid Precipitation Quantity

Returns

An annual Ladybug list

monthly_cooling_design_days(percentile=5)[source]

Get a list of 12 monthly cooling design days from this EPW.

Note that these design days are always derived from analysis of the annual data within the EPW, which is usually less accurate than the monthly design days available via a STAT or DDY file. However, such data is not always availabe in these files and so this method gives a means of

Parameters

percentile – A number between 0 and 50 for the percentile difference from the most extreme conditions within each month to be used for the design day. Typical values are 10, 5, 2, and 0.4. Note that 5% aligns with an annual precentile of 0.4%. (Default: 5).

Returns

A list with 12 design day objects. These represent cooling design days ranging from January to December.

save(file_path)[source]

Write EPW object as a file.

Parameters

file_path – Text for the full path to where the file will be written.

to_ddy(file_path, percentile=0.4)[source]

Produce a DDY file with a heating + cooling design day from this EPW.

This method will first check if there is a heating or cooling design day that meets the input percentile within the EPW itself. If None is found, the heating and cooling design days will be derived from analysis of the annual data within the EPW, which is usually less accurate.

Parameters
  • file_path – Full file path for output ddy file.

  • percentile – A number between 0 and 50 for the percentile difference from the most extreme conditions within the EPW to be used for the design day. Typical values are 0.4 and 1.0. (Default: 0.4).

to_ddy_monthly_cooling(file_path, annual_percentile=0.4, monthly_percentile=5)[source]

Produce a DDY file with 1 heating and 12 cooling design days.

The heating design day represents a cold and completely dark day whereas the cooling design days represent the warmest conditions in each month. This type of DDY file is useful when the peak cooling might not be driven by warm outdoor temperatures but instead by the highest-intensity solar condition, which may not coincide with the highest temperature.

Parameters
  • file_path – Full file path for output ddy file.

  • annual_percentile – A number between 0 and 50 for the percentile difference from the most extreme annual conditions within the EPW to be used for the heating design day. Typical values are 0.4 and 1.0. (Default: 0.4).

  • monthly_percentile – A number between 0 and 50 for the percentile difference from the most extreme conditions within each month to be used for the cooling design days. Typical values are 10, 5, 2, and 0.4. (Default: 5).

to_dict()[source]

Convert the EPW to a dictionary.

to_file_string()[source]

Get a text string for the entirety of the EPW file contents.

to_mos(file_path)[source]

Translate the EPW to a MOS file that can be used as input for Modelica.

MOS files can be used as input for simulations with Spawn of EnergyPlus. They contain essentially the same information as the EPW files but just formatted in a manner that can be quickly parsed by Modelica.

Parameters

file_path – Full file path for output mos file. If the file path does not contain the .mos extension, it will be automatically added.

to_wea(file_path, hoys=None)[source]

Write a wea file from the epw file.

WEA carries radiation values from epw. Gendaymtx uses these values to generate the sky. For an annual analysis it is identical to using epw2wea.

Parameters
  • file_path – Full file path for output file.

  • hoys – List of hours of the year. Default is 0-8759.

write(file_path)[source]

Write EPW object as an .epw file and return the file path.

Parameters

file_path – Text for the full path to where the .epw file will be written.

property aerosol_optical_depth

Return annual Aerosol Optical Depth as a Ladybug Data Collection.

This is the value for Aerosol Optical Depth in thousandths. It is not currently used in EnergyPlus calculations. Missing value is .999.

property albedo

Return annual Albedo values as a Ladybug Data Collection.

The ratio (unitless) of reflected solar irradiance to global horizontal irradiance. It is not currently used in EnergyPlus.

property annual_cooling_design_day_004

A design day object representing the annual 0.4% cooling design day.

property annual_cooling_design_day_010

A design day object representing the annual 1.0% cooling design day.

property annual_heating_design_day_990

A design day object representing the annual 99.0% heating design day.

property annual_heating_design_day_996

A design day object representing the annual 99.6% heating design day.

property ashrae_climate_zone

Text for the ASHRAE climate zone, estimated from the dry bulb temperature.

Note that all climate zones that should have a “B” will have an “A” for this property because EPW files almost never have correct precipitation data. If accurate precipitation data is available from another source, the ashrae_climate_zone method in the climatezone module should be used instead.

property atmospheric_station_pressure

Return annual Atmospheric Station Pressure as a Ladybug Data Collection.

This is the station pressure in Pa at the time indicated. Valid values range from 31,000 to 120,000. (These values were chosen from the standard barometric pressure for all elevations of the World). Missing value for this field is 999999

property ceiling_height

Return annual Ceiling Height as a Ladybug Data Collection.

This is the value for ceiling height in m. (77777 is unlimited ceiling height. 88888 is cirroform ceiling.) It is not currently used in EnergyPlus calculations. Missing value is 99999

comments_1
comments_2
property cooling_design_condition_dictionary

Dictionary with ASHRAE HOF Climate Design Data for cooling conditions.

daylight_savings_end
daylight_savings_start
property days_since_last_snowfall

Return annual Days Since Last Snow Fall as a Ladybug Data Collection.

This is the value for Days Since Last Snowfall. It is not currently used in EnergyPlus calculations. Missing value is 99.

property dew_point_temperature

Return annual Dew Point Temperature as a Ladybug Data Collection.

This is the dew point temperature in C at the time indicated. Note that this is a full numeric field (i.e. 23.6) and not an integer representation with tenths. Valid values range from -70 C to 70 C. Missing value for this field is 99.9

property diffuse_horizontal_illuminance

Return annual Diffuse Horizontal Illuminance as a Ladybug Data Collection.

This is the Diffuse Horizontal Illuminance in lux. (Average amount of illuminance in hundreds of lux received from the sky (excluding the solar disk) on a horizontal surface during the number of minutes preceding the time indicated.) It is not currently used in EnergyPlus calculations. It should have a minimum value of 0; missing value for this field is 999999 and will be considered missing if greater than or equal to 999900.

property diffuse_horizontal_radiation

Return annual Diffuse Horizontal Radiation as a Ladybug Data Collection.

This is the Diffuse Horizontal Radiation in Wh/m2. (Amount of solar radiation in Wh/m2 received from the sky (excluding the solar disk) on a horizontal surface during the number of minutes preceding the time indicated.) If the field is missing ( >= 9999) or invalid ( < 0), it is set to 0. Counts of such missing values are totaled and presented at the end of the runperiod

property direct_normal_illuminance

Return annual Direct Normal Illuminance as a Ladybug Data Collection.

This is the Direct Normal Illuminance in lux. (Average amount of illuminance in hundreds of lux received directly from the solar disk on a surface perpendicular to the sun’s rays, during the number of minutes preceding the time indicated.) It is not currently used in EnergyPlus calculations. It should have a minimum value of 0; missing value for this field is 999999 and will be considered missing if greater than or equal to 999900.

property direct_normal_radiation

Return annual Direct Normal Radiation as a Ladybug Data Collection.

This is the Direct Normal Radiation in Wh/m2. (Amount of solar radiation in Wh/m2 received directly from the solar disk on a surface perpendicular to the sun’s rays, during the number of minutes preceding the time indicated.) If the field is missing ( >= 9999) or invalid ( < 0), it is set to 0. Counts of such missing values are totaled and presented at the end of the runperiod.

property dry_bulb_temperature

Return annual Dry Bulb Temperature as a Ladybug Data Collection.

This is the dry bulb temperature in C at the time indicated. Note that this is a full numeric field (i.e. 23.6) and not an integer representation with tenths. Valid values range from -70C to 70 C. Missing value for this field is 99.9.

property extraterrestrial_direct_normal_radiation

Return annual Extraterrestrial Direct Normal Radiation as a Data Collection.

This is the Extraterrestrial Direct Normal Radiation in Wh/m2. (Amount of solar radiation in Wh/m2 received on a surface normal to the rays of the sun at the top of the atmosphere during the number of minutes preceding the time indicated). It is not currently used in EnergyPlus calculations. It should have a minimum value of 0; missing value for this field is 9999.

property extraterrestrial_horizontal_radiation

Return annual Extraterrestrial Horizontal Radiation as a Data Collection.

This is the Extraterrestrial Horizontal Radiation in Wh/m2. It is not currently used in EnergyPlus calculations. It should have a minimum value of 0; missing value for this field is 9999.

property extreme_cold_weeks

A dictionary with AnalysisPeriods for the coldest weeks within the EPW.

property extreme_design_condition_dictionary

Dictionary with ASHRAE HOF Climate Design Data for extreme conditions.

property extreme_hot_weeks

A dictionary with AnalysisPeriods for the hottest week within the EPW.

property file_path

Get path to epw file.

property global_horizontal_illuminance

Return annual Global Horizontal Illuminance as a Ladybug Data Collection.

This is the Global Horizontal Illuminance in lux. (Average total amount of direct and diffuse illuminance in hundreds of lux received on a horizontal surface during the number of minutes preceding the time indicated.) It is not currently used in EnergyPlus calculations. It should have a minimum value of 0; missing value for this field is 999999 and will be considered missing if greater than or equal to 999900.

property global_horizontal_radiation

Return annual Global Horizontal Radiation as a Ladybug Data Collection.

This is the Global Horizontal Radiation in Wh/m2. (Total amount of direct and diffuse solar radiation in Wh/m2 received on a horizontal surface during the number of minutes preceding the time indicated.) It is not currently used in EnergyPlus calculations. It should have a minimum value of 0; missing value for this field is 9999.

property header

A list of text representing the full header (the first 8 lines) of the EPW.

property heating_design_condition_dictionary

Dictionary with ASHRAE HOF Climate Design Data for heating conditions.

property horizontal_infrared_radiation_intensity

Return annual Horizontal Infrared Radiation Intensity as a Data Collection.

This is the Horizontal Infrared Radiation Intensity in W/m2. If it is missing, it is calculated from the Opaque Sky Cover field as shown in the following explanation. It should have a minimum value of 0; missing value for this field is 9999.

property is_data_loaded

Return True if weather data is loaded.

property is_header_loaded

Return True if location data is loaded.

property is_ip

Returns True if the data collections of this file are in IP units.

property is_leap_year

Boolean to denote whether the EPW is a leap year or not.

property liquid_precipitation_depth

Return annual liquid precipitation depth as a Ladybug Data Collection.

The amount of liquid precipitation (mm) observed at the indicated time for the period indicated in the liquid precipitation quantity field. If this value is not missing, then it is used and overrides the “precipitation” flag as rainfall. Conversely, if the precipitation flag shows rain and this field is missing or zero, it is set to 1.5 (mm).

property liquid_precipitation_quantity

Return annual Liquid Precipitation Quantity as a Ladybug Data Collection.

The period of accumulation (hr) for the liquid precipitation depth field. It is not currently used in EnergyPlus.

property location

Return location data.

property metadata

Dictionary of metadata written to DataCollection headers.

Keys typically include “source”, “country”, and “city”).

property monthly_ground_temperature

Return a dictionary of Monthly Data collections.

The keys of this dictionary are the depths at which each set of temperatures occurs.

property opaque_sky_cover

Return annual Opaque Sky Cover as a Ladybug Data Collection.

This is the value for opaque sky cover (tenths of coverage). (i.e. 1 is 1/10 covered. 10 is total coverage). (Amount of sky dome in tenths covered by clouds or obscuring phenomena that prevent observing the sky or higher cloud layers at the time indicated.) This is not used unless the field for Horizontal Infrared Radiation Intensity is missing and then it is used to calculate Horizontal Infrared Radiation Intensity. Minimum value is 0; maximum value is 10; missing value is 99.

property precipitable_water

Return annual Precipitable Water as a Ladybug Data Collection.

This is the value for Precipitable Water in mm. (This is not rain - rain is inferred from the PresWeathObs field but a better result is from the Liquid Precipitation Depth field). It is not currently used in EnergyPlus calculations (primarily due to the unreliability of the reporting of this value). Missing value is 999.

property present_weather_codes

Return annual Present Weather Codes as a Ladybug Data Collection.

The present weather codes field is assumed to follow the TMY2 conventions for this field. Note that though this field may be represented as numeric (e.g. in the CSV format), it is really a text field of 9 single digits. This convention along with values for each “column” (left to right) is presented in Table 16. Note that some formats (e.g. TMY) does not follow this convention - as much as possible, the present weather codes are converted to this convention during WeatherConverter processing. Also note that the most important fields are those representing liquid precipitation - where the surfaces of the building would be wet. EnergyPlus uses “Snow Depth” to determine if snow is on the ground.

property present_weather_observation

Return annual Present Weather Observation as a Ladybug Data Collection.

If the value of the field is 0, then the observed weather codes are taken from the following field. If the value of the field is 9, then “missing” weather is assumed. Since the primary use of these fields (Present Weather Observation and Present Weather Codes) is for rain/wet surfaces, a missing observation field or a missing weather code implies no rain.

property relative_humidity

Return annual Relative Humidity as a Ladybug Data Collection.

This is the Relative Humidity in percent at the time indicated. Valid values range from 0% to 110%. Missing value for this field is 999.

property sky_temperature

Return annual Sky Temperature as a Ladybug Data Collection.

This value in degrees Celsius is derived from the Horizontal Infrared Radiation Intensity in Wh/m2. It represents the long wave radiant temperature of the sky Read more at: https://bigladdersoftware.com/epx/docs/9-6/engineering-reference/climate-calculations.html#energyplus-sky-temperature-calculation

property snow_depth

Return annual Snow Depth as a Ladybug Data Collection.

This is the value for Snow Depth in cm. This field is used to tell when snow is on the ground and, thus, the ground reflectance may change. Missing value is 999.

property total_sky_cover

Return annual Total Sky Cover as a Ladybug Data Collection.

This is the value for total sky cover (tenths of coverage). (i.e. 1 is 1/10 covered. 10 is total coverage). (Amount of sky dome in tenths covered by clouds or obscuring phenomena at the hour indicated at the time indicated.) Minimum value is 0; maximum value is 10; missing value is 99.

property typical_weeks

A dictionary with AnalysisPeriods for the typical weeks within the EPW.

property visibility

Return annual Visibility as a Ladybug Data Collection.

This is the value for visibility in km. (Horizontal visibility at the time indicated.) It is not currently used in EnergyPlus calculations. Missing value is 9999.

property wind_direction

Return annual Wind Direction as a Ladybug Data Collection.

This is the Wind Direction in degrees where the convention is that North=0.0, East=90.0, South=180.0, West=270.0. (Wind direction in degrees at the time indicated. If calm, direction equals zero.) Values can range from 0 to 360. Missing value is 999.

property wind_speed

Return annual Wind Speed as a Ladybug Data Collection.

This is the wind speed in m/sec. (Wind speed at time indicated.) Values can range from 0 to 40. Missing value is 999.

property years

Return years as a Ladybug Data Collection.

property zenith_luminance

Return annual Zenith Luminance as a Ladybug Data Collection.

This is the Zenith Illuminance in Cd/m2. (Average amount of luminance at the sky’s zenith in tens of Cd/m2 during the number of minutes preceding the time indicated.) It is not currently used in EnergyPlus calculations. It should have a minimum value of 0; missing value for this field is 9999.

class ladybug.epw.EPWField(field_dict)[source]

Bases: object

An EPW field.

Parameters
  • name – Name of the field.

  • value_type – field value type (e.g. int, float, str)

  • unit – Field unit.

  • missing – Missing value for the data type in EPW files.

missing
name
unit
value_type
class ladybug.epw.EPWFields[source]

Bases: object

EPW weather file fields.

Read more at https://bigladdersoftware.com/epx/docs/9-6/auxiliary-programs/energyplus-weather-file-epw-data-dictionary.html

classmethod field_by_number(field_number)[source]

Return an EPWField based on field number.

  • 0 Year

  • 1 Month

  • 2 Day

  • 3 Hour

  • 4 Minute

  • 5 -

  • 6 Dry Bulb Temperature

  • 7 Dew Point Temperature

  • 8 Relative Humidity

  • 9 Atmospheric Station Pressure

  • 10 Extraterrestrial Horizontal Radiation

  • 11 Extraterrestrial Direct Normal Radiation

  • 12 Horizontal Infrared Radiation Intensity

  • 13 Global Horizontal Radiation

  • 14 Direct Normal Radiation

  • 15 Diffuse Horizontal Radiation

  • 16 Global Horizontal Illuminance

  • 17 Direct Normal Illuminance

  • 18 Diffuse Horizontal Illuminance

  • 19 Zenith Luminance

  • 20 Wind Direction

  • 21 Wind Speed

  • 22 Total Sky Cover

  • 23 Opaque Sky Cover

  • 24 Visibility

  • 25 Ceiling Height

  • 26 Present Weather Observation

  • 27 Present Weather Codes

  • 28 Precipitable Water

  • 29 Aerosol Optical Depth

  • 30 Snow Depth

  • 31 Days Since Last Snowfall

  • 32 Albedo

  • 33 Liquid Precipitation Depth

  • 34 Liquid Precipitation Quantity