Hourly Weather Attribute Forecast Explanation

Most weather variables represent instantaneous data at a specific point in time, such as temperature and humidity, which indicate the current conditions. However, some variables (such as precipitation) are calculated as averages or totals starting from the previous hour.

Variable Name	Valid Time	Unit	Variable Type	Description
weather_code	Instantaneous	-	Basic Variable	Weather code. Represents weather conditions in numerical codes. Follows the WMO weather interpretation codes. Refer to Weather Code Explanation.
temperature_2m	Instantaneous	°C	Basic Variable	Temperature (2m). Temperature 2 meters above the ground.
temperature_80m	Instantaneous	°C	Basic Variable	Temperature (80m). Temperature 80 meters above the ground.
temperature_120m	Instantaneous	°C	Basic Variable	Temperature (120m). Temperature 120 meters above the ground.
temperature_180m	Instantaneous	°C	Basic Variable	Temperature (180m). Temperature 180 meters above the ground.
apparent_temperature	Instantaneous	°C	Basic Variable	Apparent temperature. Perceived temperature combining wind chill factor, relative humidity, and solar radiation.
pressure_msl	Instantaneous	hPa	Basic Variable	Mean sea-level pressure. Generally used as the average pressure at sea level in meteorology.
surface_pressure	Instantaneous	hPa	Basic Variable	Surface pressure. Decreases with altitude.
visibility	Instantaneous	m	Basic Variable	Visibility in meters. Influenced by low clouds, humidity, and aerosols. Maximum visibility is around 24 kilometers.
is_day	Instantaneous	-	Basic Variable	Day or night. 1 for daytime, 0 for nighttime.
relative_humidity_2m	Instantaneous	%	Rain/Snow Variable	Relative humidity (2m). Relative humidity at 2 meters above the ground.
dew_point_2m	Instantaneous	°C	Rain/Snow Variable	Dew point (2m). Dew point temperature at 2 meters above the ground.
precipitation_probability	Previous Hour Probability	%	Rain/Snow Variable	Precipitation probability. Probability of precipitation exceeding 0.1 mm in the previous hour. Based on a 0.25° resolution (~27 km) ensemble weather model. Calculated from 30 different simulations to better represent future weather conditions.
precipitation	Previous Hour Total	mm	Rain/Snow Variable	Precipitation. Total precipitation (rain, showers, snow) in the previous hour.
rain	Previous Hour Total	mm	Rain/Snow Variable	Rainfall. Total rainfall in the previous hour.
showers	Previous Hour Total	mm	Rain/Snow Variable	Showers. Total convective precipitation in the previous hour (in mm).
snowfall	Previous Hour Total	cm	Rain/Snow Variable	Snowfall. Total snowfall in the previous hour, in cm. For water equivalent in mm, divide by 7. For example, 7 cm of snow = 10 mm of precipitation water equivalent.
snow_depth	Instantaneous	m	Rain/Snow Variable	Snow depth. Depth of snow on the ground.
freezing_level_height	Instantaneous	m	Rain/Snow Variable	Freezing level height. Altitude where the temperature is 0°C.
cloud_cover	Instantaneous	%	Cloud Variable	Cloud cover. Represents total cloud cover.
cloud_cover_low	Instantaneous	%	Cloud Variable	Low cloud cover, within 3 km altitude.
cloud_cover_mid	Instantaneous	%	Cloud Variable	Mid-level cloud cover, between 3 to 8 km altitude.
cloud_cover_high	Instantaneous	%	Cloud Variable	High-level cloud cover, above 8 km altitude.
wind_speed_10m	Instantaneous	km/h	Wind Variable	Wind speed (10m). Wind speed at 10 meters above the ground.
wind_speed_80m	Instantaneous	km/h	Wind Variable	Wind speed (80m). Wind speed at 80 meters above the ground.
wind_speed_120m	Instantaneous	km/h	Wind Variable	Wind speed (120m). Wind speed at 120 meters above the ground.
wind_speed_180m	Instantaneous	km/h	Wind Variable	Wind speed (180m). Wind speed at 180 meters above the ground.
wind_direction_10m	Instantaneous	°	Wind Variable	Wind direction (10m). Wind direction at 10 meters above the ground.
wind_direction_80m	Instantaneous	°	Wind Variable	Wind direction (80m). Wind direction at 80 meters above the ground.
wind_direction_120m	Instantaneous	°	Wind Variable	Wind direction (120m). Wind direction at 120 meters above the ground.
wind_direction_180m	Instantaneous	°	Wind Variable	Wind direction (180m). Wind direction at 180 meters above the ground.
wind_gusts_10m	Previous Hour Maximum	km/h	Wind Variable	Wind gusts (10m). Maximum wind gusts at 10 meters above the ground in the previous hour.
cape	Instantaneous	J/kg	Wind Variable	Convective available potential energy.
evapotranspiration	Previous Hour Total	mm	Soil Variable	Evapotranspiration. Model assumes evaporation from the ground and plants at the location, considering available soil water. Each hour of 1 mm evaporation equals 1 liter of water per square meter.
et0_fao_evapotranspiration	Previous Hour Total	mm	Soil Variable	Reference evapotranspiration.
vapour_pressure_deficit	Instantaneous	kPa	Soil Variable	Vapor pressure deficit (VPD). Measured in kilopascals (kPa). High VPD (>1.6) increases plant transpiration, while low VPD (<0.4) reduces transpiration.
soil_temperature_0cm	Instantaneous	°C	Soil Variable	Soil temperature (0cm). Temperature at 0 cm depth in the soil. Represents surface temperature on land or water surface.
soil_temperature_6cm	Instantaneous	°C	Soil Variable	Soil temperature (6cm). Temperature at 6 cm depth in the soil.
soil_temperature_18cm	Instantaneous	°C	Soil Variable	Soil temperature (18cm). Temperature at 18 cm depth in the soil.
soil_temperature_54cm	Instantaneous	°C	Soil Variable	Soil temperature (54cm). Temperature at 54 cm depth in the soil.
soil_moisture_0_to_1cm	Instantaneous	m³	Soil Variable	Soil moisture (0-1cm). Average soil water content in volume mixing ratio at 0-1 cm depth.
soil_moisture_1_to_3cm	Instantaneous	m³	Soil Variable	Soil moisture (1-3cm). Average soil water content in volume mixing ratio at 1-3 cm depth.
soil_moisture_3_to_9cm	Instantaneous	m³	Soil Variable	Soil moisture (3-9cm). Average soil water content in volume mixing ratio at 3-9 cm depth.
soil_moisture_9_to_27cm	Instantaneous	m³	Soil Variable	Soil moisture (9-27cm). Average soil water content in volume mixing ratio at 9-27 cm depth.
soil_moisture_27_to_81cm	Instantaneous	m³	Soil Variable	Soil moisture (27-81cm). Average soil water content in volume mixing ratio at 27-81 cm depth.
uv_index	Instantaneous	-	Light Variable	UV index. Using index scale.
uv_index_clear_sky	Instantaneous	-	Light Variable	UV index (clear sky). Using index scale.
sunshine_duration	Previous Hour Total	seconds	Light Variable	Sunshine duration. Total seconds of sunshine in the previous hour.
shortwave_radiation	Previous Hour Average	W/m²	Solar Radiation Variable	Shortwave solar radiation GHI. Average value in the previous hour, equivalent to global horizontal irradiance.
direct_radiation	Previous Hour Average	W/m²	Solar Radiation Variable	Direct solar radiation. Average direct solar radiation in the previous hour on horizontal and normal (perpendicular to the sun) planes.
diffuse_radiation	Previous Hour Average	W/m²	Solar Radiation Variable	Diffuse solar radiation DHI. Average value in the previous hour.
direct_normal_irradiance	Previous Hour Average	W/m²	Solar Radiation Variable	Direct normal irradiance DNI. Average value in the previous hour.
global_tilted_irradiance	Previous Hour Average	W/m²	Solar Radiation Variable	Global tilted irradiance GTI.
terrestrial_radiation	Previous Hour Average	W/m²	Solar Radiation Variable	Terrestrial radiation.
shortwave_radiation_instant	Instantaneous	W/m²	Solar Radiation Variable	Shortwave solar radiation GHI (instantaneous).
direct_radiation_instant	Instantaneous	W/m²	Solar Radiation Variable	Direct solar radiation (instantaneous).
diffuse_radiation_instant	Instantaneous	W/m²	Solar Radiation Variable	Diffuse solar radiation DHI (instantaneous).
direct_normal_irradiance_instant	Instantaneous	W/m²	Solar Radiation Variable	Direct normal irradiance DNI (instantaneous).
global_tilted_irradiance_instant	Instantaneous	W/m²	Solar Radiation Variable	Global tilted irradiance GTI (instantaneous).
terrestrial_radiation_instant	Instantaneous	W/m²	Solar Radiation Variable	Terrestrial radiation (instantaneous).