Parameters

name	unit	type	precision	description	notes	requiredScope
subsurfaceTemp20cm	Celsius	float	1	The temperature measured 15-34 centimeters below the surface, typically in soil or other substrates.	None
subsurfaceTemp5cm	Celsius	float	1	The temperature measured 7 centimeters or less below the surface, typically in soil or other substrates.	None
surfaceConductivity4	mhos/cm	float	2	An RWIS parameter. Indicates the ability of the road surface to conduct electrical current, which can be useful for assessing the presence of moisture, salts, or other substances that affect road conditions.	None
surfaceConductivity5	mhos/cm	float	2	An RWIS parameter. Indicates the ability of the road surface to conduct electrical current, which can be useful for assessing the presence of moisture, salts, or other substances that affect road conditions.	None
surfaceConductivity3	mhos/cm	float	2	An RWIS parameter. Indicates the ability of the road surface to conduct electrical current, which can be useful for assessing the presence of moisture, salts, or other substances that affect road conditions.	None
surfaceConductivity2	mhos/cm	float	2	An RWIS parameter. Indicates the ability of the road surface to conduct electrical current, which can be useful for assessing the presence of moisture, salts, or other substances that affect road conditions.	None
surfaceConductivity6	mhos/cm	float	2	An RWIS parameter. Indicates the ability of the road surface to conduct electrical current, which can be useful for assessing the presence of moisture, salts, or other substances that affect road conditions.	None
subsurfaceTemp5	Celsius	float	1	The temperature measured below the surface, typically in soil, rock, or other underground materials.	None
pressureChange3Hour	hPA	float	0	The change in air pressure over a 3-hour period.	This parameter provides information on the change in air pressure over a 3-hour interval, which can be useful for weather forecasting and analysis.
surfaceTemp9	Celsius	float	1	Temperature of the road (pavement) surface, usually used for winter road maintenance.	RWIS stations often have multiple sensors, where a station has more than 1 these are labelled as surfaceTemp2 to surfaceTemp12. surfaceTemp is not exclusive to networkType RWIS, other networkTypes may have this parameter.
surfaceTemp12	Celsius	float	1	Temperature of the road (pavement) surface, usually used for winter road maintenance.	RWIS stations often have multiple sensors, where a station has more than 1 these are labelled as surfaceTemp2 to surfaceTemp12. surfaceTemp is not exclusive to networkType RWIS, other networkTypes may have this parameter.
waterThickness	mm	float	2	The measurement of the depth of water or water film on a surface, such as a roadway or pavement.	None
surfaceCondition1		integer	2	Describes the current state of a surface, such as roads or bridges, based on weather and environmental factors.	None
chemicalFactor	n/a	float	2	A numerical value indicating the effectiveness of de-icing or anti-icing chemicals applied to the road surface.	None
sunrise	UTC	string	2	UTC time of sunrise for this station on the valid date.	Not directly observed - derived from the station position.	read:one-observations-public, weather.observations.core:read
precipAcc6Hour	mm	float	2	Amount of liquid precipitation (typically rain) measured in the 6 hours before the valid timestamp.	None	read:one-observations-public, weather.observations.core:read
chemicalPercent	percent	float	2	The percentage of chemical concentration present on the road surface. It represents the proportion of de-icing chemicals (such as salt brine or calcium chloride) in the surface moisture.	None
icePercent	percent	float	2	The proportion of ice relative to the total surface moisture on the road.	None
surfaceCondition		string	2	Describes the current state of a surface, such as roads or bridges, based on weather and environmental factors.	None
subsurfaceTemp10	Celsius	float	1	The temperature measured below the surface, typically in soil, rock, or other underground materials.	None
windChill	Celsius	float	2	Represents the perceived decrease in air temperature felt by the skin due to the combined effect of wind and cold temperature.	None
subsurfaceTemp2	Celsius	float	1	The temperature measured below the surface, typically in soil, rock, or other underground materials.	None
subsurfaceTemp50cm	Celsius	float	1	The temperature measured 35-74 centimeters below the surface, typically in soil or other substrates.	None
precipIntensity	n/a	string	2	Measures the rate at which precipitation (rain, snow, etc.) is falling, typically in millimeters per hour or inches per hour.	None
metarWx	code	code	2	Plain English description of present weather conditions derived directly from METAR code.	Example: ‘+TS’ in original METAR would be expressed as ‘heavy thunderstorm’
snowDepth	mm	float	2	The measure of accumulated snow thickness on the ground surface in millimeters.	This is total snow depth at a given time, not freshly added snow over a period.
waterLevel	mm	float	2	Measured water level or accumulated water depth, typically representing surface water depth at a given location.	Reported in millimeters (mm). Typically used for monitoring flooding, surface runoff, or standing water conditions. The reference level (e.g., sensor height or ground level) must be known to interpret absolute water depth accurately.
precipType		string	0	Identifies the type of precipitation occurring, such as rain, snow, sleet, or hail.	None
subsurfaceTemp10cm	Celsius	float	1	The temperature measured 8-14 centimeters below the surface, typically in soil or other substrates.	None
airTemp5cmMax1Hour	Celsius	float	1	Maximum temperature measured near the ground at a height of 5 centimeters, over the past 1 hour.	None
leafWetness	index	float	2	Presence of surface moisture on a crop.	With range from 0 (completely dry) to 15 (saturated).
subsurfaceTemp100cm	Celsius	float	1	The temperature measured 75-149 centimeters below the surface, typically in soil or other substrates.	None
subsurfaceTemp150cm	Celsius	float	1	The temperature measured 150 centimeters or more below the surface, typically in soil or other substrates.	None
surfaceTemp10	Celsius	float	1	Temperature of the road (pavement) surface, usually used for winter road maintenance.	RWIS stations often have multiple sensors, where a station has more than 1 these are labelled as surfaceTemp2 to surfaceTemp12. surfaceTemp is not exclusive to networkType RWIS, other networkTypes may have this parameter.
windGust2m	m/s	float	2	Wind gust speed 2m above the surface, normally a 3 second average sampled in the 10 minute before the valid timestamp.	This height is an approximation for data sources where we know or it is reasonable to assume that winds will be measured closer to 2m than 10m. As a general rule 10m wind speeds will be 30% higher than 2m.	read:one-observations-public, weather.observations.core:read
windGust	m/s	float	2	Wind gust speed 10m above the surface, normally a 3 second average sampled in the 10 minute before the valid timestamp.	Exact height of measurement is 10m for networks which conform to WMO standards (METAR and SYNOP).	read:one-observations-public, weather.observations.core:read
windDirectionAvg24Hour	degree	float	0	Wind direction averaged over the 24 hours before the valid time	None	read:one-observations-public, weather.observations.core:read
windDirection	degree	float	0	Compass direction the corresponding windSpeed10m is coming from.	Exact height of measurement is 10m for networks which conform to WMO standards (METAR and SYNOP).	read:one-observations-public, weather.observations.core:read
visibility	km	float	2	Horizontal visibility.	Maximum visibility value may vary depending on source.	read:one-observations-public, weather.observations.core:read
sunshine60Min	minutes	integer	None	Number of minutes of sunshine (sun unobscured by cloud) over the hour before the observation time.	None	read:one-observations-public, weather.observations.core:read
sunshine24Hour	minutes	integer	None	Number of minutes of sunshine (sun unobscured by cloud) over the 24 hours before the observation time.	None	read:one-observations-public, weather.observations.core:read
dewPointMax2m	Celsius	float	1	Maximum dew point temperature measured at a height of 2 meters above ground within a specified observation period.	None
subsurfaceTemp8	Celsius	float	1	The temperature measured below the surface, typically in soil, rock, or other underground materials.	None
airTempAvg2m	Celsius	float	1	Average temperature measured near the ground at a height of 2 centimeters, over the past 10 minutes.	None
cloudBase	m	float	1	The observed altitude of the base of the clouds, aka ceiling height.	When we talk about a cloud base of 3,000 ft, we usually mean that there is broken or more cloud from 3,000 ft.
seaSurfaceTemp	Celsius	float	1	The temperature of the seawater at or near the surface, measured at coastal or offshore locations.	None
altimeter	hpa	float	2	Air pressure corrected to / valid at mean sea level for the purpose of aircraft instrument calibration.	Roughly equivalent to pressureMsl but will start to deviate significantly at higher elevations (>1km)
precipRate	mm/hr	float	2	Precipitation rate or intensity, in mm per hour.	Can be effectively taken as precipAcc60Min (mm) assuming the precip at observed time was constant over the previous hour. If precipRate is given every 10 minutes, divide by 6 to get precipAcc10Min equivalent.
dewPointMin2m	Celsius	float	1	Minimum dew point temperature measured at a height of 2 meters above ground within a specified observation period.	Used primarily for assessing moisture availability and frost formation potential; differs from instantaneous dew point by representing the lowest observed value during a given timeframe.
wbgt	Celsius	float	1	Wet Bulb Globe Temperature (WBGT) is a measure of the heat stress in direct sunlight, which takes into account: temperature, humidity, wind speed, sun angle and cloud cover (solar radiation).	None
heatingDegreeUS24Hour	Celsius	float	1	Degree days indicating heating demand based on outdoor temperatures; calculated when average daily temperature is below 65°F (18.3°C).	None
coolingDegreeUS24Hour	Celsius	float	1	Degree days indicating cooling demand based on outdoor temperatures; calculated when average daily temperature is above 65°F (18.3°C).	None
windSpeed2m	m/s	float	2	Wind speed 2m above the surface, normally averaged over 10 minutes.	This height is an approximation for data sources where we know or it is reasonable to assume that winds will be measured closer to 2m than 10m. As a general rule 10m wind speeds will be 30% higher than 2m.	read:one-observations-public, weather.observations.core:read
windGust3Hour	m/s	float	2	Maximum observed wind gust speed 10m above the surface during the 3 hours before the valid timestamp.	Exact height of measurement is 10m for networks which conform to WMO standards (METAR and SYNOP).	read:one-observations-public, weather.observations.core:read
windDirection2m	degree	float	0	Compass direction the corresponding windSpeed2m is coming from.	This height is an approximation for data sources where we know or it is reasonable to assume that winds will be measured closer to 2m than 10m. As a general rule 10m wind speeds will be 30% higher than 2m.	read:one-observations-public, weather.observations.core:read
globalRadiation10Min	joules per square centimeter	string	None	Total solar radiation accumulated over the past 10 minutes.	None	read:one-observations-public, weather.observations.core:read
soilMoisture	percent	float	2	The moisture level of the soil.	Stations may have multiple sensors and depths, currently the api exposes the deepest value available. In future multiple depths and sensors will be supported.
metarSky	code	string	None	Raw METAR code describing cloud cover, height and type - used for aviation purposes.	Example: FEW005 SCT010CB BKN025 means 'few at five hundred feet, scattered cumulonimbus at one thousand feet, broken at two thousand five hundred feet'. Up to three, but occasionally more, cloud groups may be reported. Further decoding information is widely available online.
subsurfaceTemp	Celsius	float	1	The temperature measured below the surface, typically in soil, rock, or other underground materials.	None
airTempMin	Celsius	float	1	Minimum temperature measured near the ground at a height of 2 centimeters, over the past 10 minutes.	None
precipAcc3Hour	mm	float	2	Amount of liquid precipitation (typically rain) measured in the 3 hours before the valid timestamp.	None	read:one-observations-public, weather.observations.core:read
precipAcc12Hour	mm	float	2	Amount of liquid precipitation (typically rain) measured in the 12 hours before the valid timestamp.	None	read:one-observations-public, weather.observations.core:read
precipAcc10Min	mm	float	2	Amount of liquid precipitation (typically rain) measured in the 10 minutes before the valid timestamp.	None	read:one-observations-public, weather.observations.core:read
sunset	UTC	string	2	UTC time of sunset for this station on the valid date.	Not directly observed - derived from the station position.	read:one-observations-public, weather.observations.core:read
globalRadiation60Min	joules per square centimeter	float	None	Solar radiation integrated over the previous hour.	This can be effectively converted to the instantaneous solarRadiation by dividing by 0.36, assuming the radiation at the end of the hour = the average of the previous hour.	read:one-observations-public, weather.observations.core:read
globalRadiation24Hour	joules per square centimeter	float	None	Total solar radiation accumulated over the past 24 hours.	Can be reported at source or aggregated by our API over any daily period by specifying interval=24h in observations endpoint.	read:one-observations-public, weather.observations.core:read
soilTemp	Celsius	float	1	Temperature of soil at a given depth.	Stations may have multiple sensors and depths, currently the api exposes the deepest value available. In future multiple depths and sensors will be supported.
cloudCover	percent	float	2	Percentage of the sky covered by cloud. 100% = overcast, 0% = blue sky.	Not to be confused with ‘effective cloud cover’. Sky can still be bright with 100% totalCloud if cloud is high/thin. For Metars this parameter is derived from given cloud groups (SCT/BKN etc.) therefore has limited precision. Multiply by 0.08 to convert to oktas.	read:one-observations-public, weather.observations.core:read
airTempMin24Hour	Celsius	float	1	Minimum air temperature 2m above the surface, measured in the 24 hours before the valid time.	Can be reported at source or aggregated by our API over any daily period by specifying interval=24h in observations endpoint.	read:one-observations-public, weather.observations.core:read
airTempMax24Hour	Celsius	float	1	Maximum air temperature 2m above the surface, measured in the 24 hours before the valid time.	Can be reported at source or aggregated by our API over any daily period by specifying interval=24h in observations endpoint.	read:one-observations-public, weather.observations.core:read
airTempMax12Hour	Celsius	float	1	Maximum air temperature 2m above the surface, measured in the 12 hours before the valid time.	Reported at source. We do not currently aggregate data from lower time periods to higher time periods.	read:one-observations-public, weather.observations.core:read
airTemp5cm	Celsius	float	1	Temperature measured near the ground at a height of 5 centimeters	Available predominately via DTN EU network	read:one-observations-public, weather.observations.core:read
airTemp	Celsius	float	1	Instantaneous air temperature 2m above the surface.	Exact height of measurement is 2m for networks which conform to WMO standards (Metar and Synop). This cannot be guaranteed for all sources but deviations in air temperatures at most surface measurement heights will be trivial.	read:one-observations-public, weather.observations.core:read
airTempMax1Hour	Celsius	float	1	Maximum air temperature 2m above the surface, measured in the 1 hour before the valid time.	Reported at source. We do not currently aggregate data from lower time periods to higher time periods.	read:one-observations-public, weather.observations.core:read
surfaceTemp4	Celsius	float	1	Temperature of the road (pavement) surface, usually used for winter road maintenance.	RWIS stations often have multiple sensors, where a station has more than 1 these are labelled as surfaceTemp2 to surfaceTemp12. surfaceTemp is not exclusive to networkType RWIS, other networkTypes may have this parameter.
gradtagzahlBasic24Hour	Celsius	float	1	German heating degree day, with a base temperature of 20C, only calculated when daily average airTemp falls below 15. Valid for Kalendertag if 00-00 UTC, Gastag if aggregated 06-06 local time.	None
iceThickness	mm	float	2	The measurement of solid ice from the top surface to the underlying substrate, such as water or ground.	None
windSpeed	m/s	float	2	Wind speed 10m above the surface averaged over 10 minutes.	Exact height of measurement is 10m for networks which conform to WMO standards (METAR and SYNOP).	read:one-observations-public, weather.observations.core:read
seaWaterTemp	Celsius	float	1	The temperature of the water close to the ocean’s surface.	None
sunshine10Min	minutes	float	None	Number of minutes of sunshine (sun unobscured by cloud) over the 10 minutes before the observation time.	None	read:one-observations-public, weather.observations.core:read
precipAcc60Min	mm	float	2	Amount of liquid precipitation (typically rain) measured in the 1 hour before the valid timestamp.	We do not currently sum or aggregate from sub-hourly precipitation to get to precip60Min but this is often done at source. The parameter ‘precip’ is a value for accumulated precipitation and may also be useful although its exact definition depends on its source.	read:one-observations-public, weather.observations.core:read
precipAcc24Hour	mm	float	2	Amount of liquid precipitation (typically rain) measured in the 24 hours before the valid timestamp.	Can be reported at source or aggregated by our API over any daily period by specifying interval=24h in observations endpoint. Values from NOAA_GHCND are stored with default timestamp 1111UTC where the true timestamp is not known.	read:one-observations-public, weather.observations.core:read
dewPoint	Celsius	float	1	Dew point temperature 2m above the surface. The temperature to which the air must be cooled for saturation and condensation to occur.	Exact height of measurement is 2m for networks which conform to WMO standards (Metar and Synop). This cannot be guaranteed for all sources but deviations in air temperatures at most surface measurement heights will be trivial.	read:one-observations-public, weather.observations.core:read
wavePeakPeriod	seconds	float	2	The period of the most energetic waves where period is the time it takes for two consecutive wave crests, on the surface of the ocean/sea, to pass through a fixed point.	None
seaWaterSalinity	g/kg	float	2	The salt concentration in sea water.	None
waveDirection	degrees	float	None	The mean direction of ocean/sea surface waves generated by local winds and swell.	None
eastwardCurrent	m/s	float	None	The speed of the component of the sea current travelling towards the east. Negative is westerly.	None
northwardCurrent	m/s	float	None	The speed of the component of the sea current travelling towards the north. Negative is southerly.	None
significantWaveHeight	metres	float	2	The mean wave height (trough to crest) of the highest third of the waves.	None
wmoWeatherCode	code	integer	0	WMO weather code corresponding to table 4677.	See reference table on https://www.nodc.noaa.gov/archive/arc0021/0002199/1.1/data/0-data/HTML/WMO-CODE/WMO4677.HTM	read:one-observations-public, weather.observations.core:read
windGust6Hour	m/s	float	None	Maximum observed wind gust speed 10m above the surface during the 6 hours before the valid timestamp.	Exact height of measurement is 10m for networks which conform to WMO standards (METAR and SYNOP).	read:one-observations-public, weather.observations.core:read
windGust60Min	m/s	float	2	Maximum observed wind gust speed 10m above the surface during the 1 hour before the valid timestamp.	Exact height of measurement is 10m for networks which conform to WMO standards (METAR and SYNOP).	read:one-observations-public, weather.observations.core:read
windSpeedAvg24Hour	m/s	float	2	Wind speed 10m above the surface, averaged over the 24 hours before the valid time	None	read:one-observations-public, weather.observations.core:read
windGustMax24Hour	m/s	float	2	Maximum wind gust speed 10m above the surface, observed in the 24 hours before the valid time.	None	read:one-observations-public, weather.observations.core:read
subsurfaceTemp13	Celsius	float	1	The temperature measured below the surface, typically in soil, rock, or other underground materials.	None
wmoWeatherCode4680	code	integer	0	WMO weather code corresponding to table 4680.	Limited availability, use wmoWeatherCode in most cases.
subsurfaceTemp15	Celsius	float	1	The temperature measured below the surface, typically in soil, rock, or other underground materials.	None
subsurfaceTemp4	Celsius	float	1	The temperature measured below the surface, typically in soil, rock, or other underground materials.	None
subsurfaceTemp6	Celsius	float	1	The temperature measured below the surface, typically in soil, rock, or other underground materials.	None
subsurfaceTemp7	Celsius	float	1	The temperature measured below the surface, typically in soil, rock, or other underground materials.	None
subsurfaceTemp9	Celsius	float	1	The temperature measured below the surface, typically in soil, rock, or other underground materials.	None
subsurfaceTemp11	Celsius	float	1	The temperature measured below the surface, typically in soil, rock, or other underground materials.	None
wetBulb	Celsius	float	1	The temperature read by a well-ventilated thermometer covered in water-soaked cloth.	At 100% relative humidity, the wet-bulb temperature is equal to the air temperature; at lower humidity the wet-bulb temperature is lower than dry-bulb temperature because of evaporative cooling.
fuelMoisture	percent	float	2	Fuel moisture is a measure of the amount of water in a fuel (vegetation) available to a fire
windSpeedMax60Min	m/s	float	2	Maximum observed wind speed at 10m above the surface during the 60 minutes before the valid timestamp. Reflects highest instantaneous wind speed.	None	read:one-observations-public, weather.observations.core:read
surfaceTemp2	Celsius	float	1	Temperature of the road (pavement) surface, usually used for winter road maintenance.	RWIS stations often have multiple sensors, where a station has more than 1 these are labelled as surfaceTemp2 to surfaceTemp12. surfaceTemp is not exclusive to networkType RWIS, other networkTypes may have this parameter.
freshSnowDepth	mm	float	2	The newly added / fresh amount of of accumulated snow in millimeters, since the last observation.	This is freshly added snow, for total snow depth use snowDepth.
subsurfaceTemp14	Celsius	float	1	The temperature measured below the surface, typically in soil, rock, or other underground materials.	None
subsurfaceTemp12	Celsius	float	1	The temperature measured below the surface, typically in soil, rock, or other underground materials.	None
subsurfaceTemp3	Celsius	float	1	The temperature measured below the surface, typically in soil, rock, or other underground materials.	None
bridgeConductivity	mhos/cm	float	2	An RWIS parameter. Indicates the ability of the bridge surface to conduct electrical current, which can be useful for assessing the presence of moisture, salts, or other substances that affect bridge conditions.	None
cycleConductivity	mhos/cm	float	2	An RWIS parameter. Indicates the ability of the cycle surface to conduct electrical current, which can be useful for assessing the presence of moisture, salts, or other substances that affect cycle conditions.	None
airTemp5cmMin1Hour	Celsius	float	1	Minimum temperature measured near the ground at a height of 5 centimeters, over the past 1 hour.	None
airTemp5cmMin24Hour	Celsius	float	1	Minimum temperature measured near the ground at a height of 5 centimeters, over the past 24 hours.	None
airTempMin1Hour	Celsius	float	1	Minimum air temperature 2m above the surface, measured in the 1 hour before the valid time.	Reported at source. We do not currently aggregate data from lower time periods to higher time periods.	read:one-observations-public, weather.observations.core:read
airTempMin12Hour	Celsius	float	1	Minimum air temperature 2m above the surface, measured in the 12 hours before the valid time.	Reported at source. We do not currently aggregate data from lower time periods to higher time periods.	read:one-observations-public, weather.observations.core:read
surfaceTemp7	Celsius	float	1	Temperature of the road (pavement) surface, usually used for winter road maintenance.	RWIS stations often have multiple sensors, where a station has more than 1 these are labelled as surfaceTemp2 to surfaceTemp12. surfaceTemp is not exclusive to networkType RWIS, other networkTypes may have this parameter.
airTempMax	Celsius	float	1	Maximum temperature measured near the ground at a height of 2 centimeters, over the past 10 minutes.	None
bridgeTemp	Celsius	float	1	Temperature of the bridge surface, usually used for winter road maintenance.	None
feelsLikeTemp	Celsius	float	1	The equivalent human perceived temperature, taking into account the combined effects of air temperature, relative humidity and wind speed.	When airTemp is less than or equal to 10 celsius, feelsLikeTemp is synonymous with windChill. If airTemp is great than or equal to 27, its synonymous with heatIndex.	read:one-observations-public, weather.observations.core:read
surfaceTemp3	Celsius	float	1	Temperature of the road (pavement) surface, usually used for winter road maintenance.	RWIS stations often have multiple sensors, where a station has more than 1 these are labelled as surfaceTemp2 to surfaceTemp12. surfaceTemp is not exclusive to networkType RWIS, other networkTypes may have this parameter.
soilTemp100cm	Celsius	float	1	Temperature of the ground 1 meter below the surface.	None
pressureTendency	n/a		0	The character and amount of atmospheric pressure change during a specified period of time.	None
airTemp5cmMax12Hour	Celsius	float	1	Maximum temperature measured near the ground at a height of 5 centimeters, over the past 12 hours.	None
airTempAvg24Hour	Celsius	float	1	Air temperature 2m above the surface, averaged over the 24 hours before the valid time	None	read:one-observations-public, weather.observations.core:read
precipEndTime	datetime	integer	2	The end time of a precipitation event. Marks when measurable precipitation ceased at the specified location.	If there is no ongoing precipitation, this will reflect the end time of the last recorded precipitation event.
airTemp5cmMax24Hour	Celsius	float	1	Maximum temperature measured near the ground at a height of 5 centimeters, over the past 24 hours.	None
airTempMin5cm	Celsius	float	1	Minimum temperature measured near the ground at a height of 5 centimetres, over the past 10 minutes.	None
airTemp5cmMin12Hour	Celsius	float	1	Minimum temperature measured near the ground at a height of 5 centimeters, over the past 12 hours.
cycleTemp	Celsius	float	1	Temperature of the cycle surface, usually used for winter road maintenance.	RWIS stations often have multiple sensors, where a station has more than 1 these are labelled as surfaceTemp2 to surfaceTemp6. surfaceTemp is not exclusive to networkType RWIS, other networkTypes may have this parameter.
stationPressure	hPA	float	0	Air pressure valid at station’s elevation.	None	read:one-observations-public, weather.observations.core:read
mslPressure	hPA	float	0	Air pressure corrected to / valid at mean sea level.	Roughly equivalent to altimeter but will start to deviate significantly at higher elevations (>1km)
windGustDirectionMax	degree	float	0	The maximum recorded direction of wind gusts over a given period, typically measured in degrees from true north (0° to 360°).	This height is an approximation for data sources where we know or it is reasonable to assume that winds will be measured closer to 2m than 10m. As a general rule 10m wind speeds will be 30% higher than 2m.
friction	mu	float	2	Refers to the grip or traction between the road surface and tires of vehicles	None
shortWaveRadiation	watts per square meter	float	2	Instantaneous solar (direct plus diffuse) radiation. Also called GHI.	This can be effectively converted to globalRadiation60Min (Jcm2) by multiplying by 0.36, assuming the solarRadiation at observed time was constant over the previous hour.
surfaceTemp8	Celsius	float	1	Temperature of the road (pavement) surface, usually used for winter road maintenance.	RWIS stations often have multiple sensors, where a station has more than 1 these are labelled as surfaceTemp2 to surfaceTemp12. surfaceTemp is not exclusive to networkType RWIS, other networkTypes may have this parameter.
surfaceConductivity	mhos/cm	float	2	An RWIS parameter. Indicates the ability of the road surface to conduct electrical current, which can be useful for assessing the presence of moisture, salts, or other substances that affect road conditions.	None
freezingTemp	Celsius	float	1	A parameter that indicates the threshold air temperature at or below which water freezes. Typically used to detect freeze events that can affect agriculture, road safety, infrastructure, and ecosystems.	None
relativeHumidity	percent	float	0	Relative humidity represents the ratio of the actual amount of water vapour in the air to the maximum amount that can physically exist at a given air temperature.	Exact height of measurement is 2m for networks which conform to WMO standards (Metar and Synop). This cannot be guaranteed for all sources but deviations in air temperatures at most surface measurement heights will be trivial.	read:one-observations-public, weather.observations.core:read
adjacentSnowDepth	mm	float	2	Represents the depth of undisturbed snow on the ground in the immediate vicinity of a weather station or sensor platform. It includes all naturally fallen snow and ice on the ground, excluding drifts or piles from snow removal.	None
iceOrWaterDepth	mm	float	2	Represents the measured depth of accumulated ice or standing water on a flat surface — such as roads, runways, sensor platforms, or natural terrain. It captures both frozen (ice, compacted snow, sleet) and liquid (rain puddles, surface water) forms, depending on conditions at the time of observation.	None
gradtagzahl24Hour	Celsius	float	1	German heating degree day with the modified +2 Celsius offset. Base temperature of 20C, only calculated when daily average airTemp falls below 15. Valid for Kalendertag if 00-00 UTC, Gastag if aggregated 06-06 local time.	None
airTempMax5cm	Celsius	float	1	Maximum temperature measured near the ground at a height of 5 centimeters, over the past 10 minutes.	None
evapotranspiration	mm	float	2	Refers to the total amount of water transferred from the land to the atmosphere through the combined processes of evaporation (from soil and water surfaces) and transpiration (from plant surfaces) over a specified time period.	None
surfaceTemp	Celsius	float	1	Temperature of the road (pavement) surface, usually used for winter road maintenance.	RWIS stations often have multiple sensors, where a station has more than 1 these are labelled as surfaceTemp2 to surfaceTemp12. surfaceTemp is not exclusive to networkType RWIS, other networkTypes may have this parameter.
surfaceTemp11	Celsius	float	1	Temperature of the road (pavement) surface, usually used for winter road maintenance.	RWIS stations often have multiple sensors, where a station has more than 1 these are labelled as surfaceTemp2 to surfaceTemp12. surfaceTemp is not exclusive to networkType RWIS, other networkTypes may have this parameter.
surfaceTemp5	Celsius	float	1	Temperature of the road (pavement) surface, usually used for winter road maintenance.	RWIS stations often have multiple sensors, where a station has more than 1 these are labelled as surfaceTemp2 to surfaceTemp12. surfaceTemp is not exclusive to networkType RWIS, other networkTypes may have this parameter.
surfaceTemp6	Celsius	float	1	Temperature of the road (pavement) surface, usually used for winter road maintenance.	RWIS stations often have multiple sensors, where a station has more than 1 these are labelled as surfaceTemp2 to surfaceTemp12. surfaceTemp is not exclusive to networkType RWIS, other networkTypes may have this parameter.
pressureTendencyInCode		integer	1	Characteristic of pressure tendency during the defined period (coded value)	None
precipStartTime	datetime	integer	2	The start time of a precipitation event. Indicates when measurable precipitation began at the specified location.	If there is no ongoing precipitation, this will reflect the start time of the last recorded precipitation event.
windSpeedMax24Hour	m/s	float	None	Maximum hourly wind speed observed over a 24-hour period.	None	read:one-observations-public, weather.observations.core:read
airTemp5cmAvg24Hour	celsius	Float	1	Air temperature at 5 cm above grass; daily mean	None