EPT-2 Family

Jua's flagship state-of-the-art weather model was first released in April 2025. The EPT-2 family outperforms leading public AI weather models including Microsoft Aurora, DeepMind's GraphCast, ECMWF's AIFS, and our previous EPT-1.5 model.

• EPT-2: Our deterministic model for precise weather forecasting

• EPT-2 Early: Our early-dissemination model delivering forecasts ahead of the market

• EPT-2e: Our ensemble model for probabilistic weather forecasting, especially for the long term

• EPT-2 RR: Our rapid-refresh model for hourly global weather intelligence

• EPT-2 HRRR: Our high-resolution rapid-refresh model

• EPT-2 Reasoning: Our AI weather forecast model with active learning from live data

For more information on our EPT-2 family of models, take a look at our EPT-2 Technical Report.

EPT-2 Family Comparison

Model	Update Frequency	Ensemble	Forecast Horizon	Global coverage
EPT-2	4 updates/day	No	20 days
EPT-2 Early	4 updates/day	No	20 days
EPT-2e	4 updates/day + 1 daily 60 day	Yes	60 days
EPT-2 RR	24 updates/day	No	2 days
EPT-2 HRRR	24 updates/day	Yes	2 days
EPT-2 Reasoning	4 updates/day	No	20 days

Live Forecast Data

• Global coverage for EPT-2, EPT-2 Early, EPT-2e, and EPT-2 RR

• European coverage for EPT-2 HRRR

• Four daily runs (00, 06, 12, 18 UTC) for EPT-2, EPT-2 Early, EPT-2e

• 24 hourly runs for EPT-2 RR and EPT-2 HRRR

• 2-day prediction horizon (EPT-2 RR, EPT-2 HRRR)

• 20-day prediction horizon (EPT-2, EPT-2 Early, EPT-2e)

• 60-day prediction horizon for the EPT-2e forecast at 00 UTC

• Real-time data access via Python SDK or REST API

Technical Specifications

Coordinates

Name	Description	Units
init_time	Initialization time of forecast at UTC	Absolute time (UTC)
prediction_timedelta	Lead time relative to initialization time	Timedelta
latitude	Latitudinal coordinate	Degrees true
longitude	Longitudinal coordinate	Degrees true

Spatial Extent

Model	Latitudes	Longitudes	Grid Size	Resolution
EPT-2	[90, -90)	[-180, 180)	2160x4320	0.081° (9 km)
EPT-2 Early	[90, -90)	[-180, 180)	1440x2880	0.125° (12 km)
EPT-2e	[90, -90)	[-180, 180)	720x1440	0.25° (25 km)
EPT-2 RR	[90, -90)	[-180, 180)	720x1440	0.25° (25 km)
EPT-2 HRRR	[36, 72]	[-15, 45]	721x1201	0.05° (5.5 km)
EPT-2 Reasoning	[90, -90)	[-180, 180)	2160x4320	0.081° (9 km)

Available Weather Parameters

EPT-2 uses standardized variable naming conventions. For full details on the naming structure, see Weather Variable Naming.

Wind speed at additional heights (20m, 40m, 60m, 80m, 120m, 140m, 160m, 180m, 200m) and air density at 2m are available from March 1, 2026 onwards.

Code	API Name	Description	Units
2t	air_temperature_at_height_level_2m	Air temperature at 2m	Kelvin
2d	dew_point_temperature_at_height_level_2m	Dew point temperature at 2m	Kelvin
r	relative_humidity_at_height_level_2m	Relative humidity at 2m	%
10si	wind_speed_at_height_level_10m	Horizontal wind speed at 10m	m s⁻¹
10wdir	wind_direction_at_height_level_10m	Horizontal wind direction at 10m	Degrees true
100si	wind_speed_at_height_level_100m	Horizontal wind speed at 100m	m s⁻¹
100wdir	wind_direction_at_height_level_100m	Horizontal wind direction at 100m	Degrees true
20si	wind_speed_at_height_level_20m	Horizontal wind speed at 20m	m s⁻¹
40si	wind_speed_at_height_level_40m	Horizontal wind speed at 40m	m s⁻¹
60si	wind_speed_at_height_level_60m	Horizontal wind speed at 60m	m s⁻¹
80si	wind_speed_at_height_level_80m	Horizontal wind speed at 80m	m s⁻¹
120si	wind_speed_at_height_level_120m	Horizontal wind speed at 120m	m s⁻¹
140si	wind_speed_at_height_level_140m	Horizontal wind speed at 140m	m s⁻¹
160si	wind_speed_at_height_level_160m	Horizontal wind speed at 160m	m s⁻¹
180si	wind_speed_at_height_level_180m	Horizontal wind speed at 180m	m s⁻¹
200si	wind_speed_at_height_level_200m	Horizontal wind speed at 200m	m s⁻¹
2rho	air_density_at_height_level_2m	Air density at 2m	kg m⁻³
msl	air_pressure_at_mean_sea_level	Mean Sea-level Pressure	Pa
lcc	low_type_cloud_area_fraction	Low Cloud Cover	%
mcc	medium_type_cloud_area_fraction	Medium Cloud Cove	%
hcc	high_type_cloud_area_fraction	High Cloud Cover	%
tp	precipitation_amount_sum_1h	Total Precipitation	mm m⁻²
ssrd	surface_downwelling_shortwave_flux_sum_1h	Surface solar downward irradiance	J m⁻²
fdir	surface_direct_downwelling_shortwave_flux_sum_1h	Direct solar radiation at the surface	J m⁻²
z_500	geopotential_at_pressure_level_50000Pa	Geopotential	m² s⁻²

Note: For information on the previous naming convention used in EPT-1.5, see Legacy Naming.

EPT-2 HRRR

EPT-2 HRRR produces a subset of the EPT-2 variables.

Parameter Code	API Name	Description	Units
2t	air_temperature_at_height_level_2m	Air temperature at 2m	Kelvin
2d	dew_point_temperature_at_height_level_2m	Dew point temperature at 2m	Kelvin
r	relative_humidity_at_height_level_2m	Relative humidity at 2m	%
10si	wind_speed_at_height_level_10m	Horizontal wind speed at 10m	m s⁻¹
10wdir	wind_direction_at_height_level_10m	Horizontal wind direction at 10m	Degrees true
100si	wind_speed_at_height_level_100m	Horizontal wind speed at 100m	m s⁻¹
100wdir	wind_direction_at_height_level_100m	Horizontal wind direction at 100m	Degrees true
20si	wind_speed_at_height_level_20m	Horizontal wind speed at 20m	m s⁻¹
40si	wind_speed_at_height_level_40m	Horizontal wind speed at 40m	m s⁻¹
60si	wind_speed_at_height_level_60m	Horizontal wind speed at 60m	m s⁻¹
80si	wind_speed_at_height_level_80m	Horizontal wind speed at 80m	m s⁻¹
120si	wind_speed_at_height_level_120m	Horizontal wind speed at 120m	m s⁻¹
140si	wind_speed_at_height_level_140m	Horizontal wind speed at 140m	m s⁻¹
160si	wind_speed_at_height_level_160m	Horizontal wind speed at 160m	m s⁻¹
180si	wind_speed_at_height_level_180m	Horizontal wind speed at 180m	m s⁻¹
200si	wind_speed_at_height_level_200m	Horizontal wind speed at 200m	m s⁻¹
2rho	air_density_at_height_level_2m	Air density at 2m	kg m⁻³
msl	air_pressure_at_mean_sea_level	Mean Sea-level Pressure	Pa
lcc	low_type_cloud_area_fraction	Low Cloud Cover	%
mcc	medium_type_cloud_area_fraction	Medium Cloud Cover	%
hcc	high_type_cloud_area_fraction	High Cloud Cover	%
tp	precipitation_amount_sum_1h	Total Precipitation	mm m⁻²
ssrd	surface_downwelling_shortwave_flux_sum_1h	Surface solar downward irradiance	J m⁻²
fdir	surface_direct_downwelling_shortwave_flux_sum_1h	Direct solar radiation at the surface	J m⁻²

Additional Variables on Request

Parameter Code	API Name	Description	Units
tcwv	atmosphere_mass_content_of_water_vapor	Total column vertically-integrated water vapour	kg m⁻²
t	air_temperature_at_pressure_level	Temperature at a specified pressure level	K
u	eastward_wind_at_pressure_level	U component of wind	m s⁻¹
v	northward_wind_at_pressure_level	V component of wind	m s⁻¹
q	specific_humidity_at_pressure_level	The mass of water vapour per kilogram of moist air at a pressure level	kg
z	geopotential_at_pressure_level	The gravitational potential energy of a unit mass	m² s⁻²

• Pressure levels: 5'000, 10'000, 15'000, 20'000, 25'000, 30'000, 40'000, 50'000, 60'000, 70'000, 85'000, 92'500, 100'000

Hindcast Data

Data Access: Hindcasts are available via our Python SDK and API. For large requests, please contact [email protected].

Model	Temporal Extent	Forecast Horizon and Resolution
EPT-2	2023-01-01 - today at 00, 06, 12, 18 UTC	480h - From 1h to 240h: hourly - From 240h to 480h: six-hourly
EPT-2e	2025-08-16 - today at 00, 06, 12, 18 UTC	00 UTC: 1440h; 06, 12, 18 UTC: 480h - From 1h to 240h: hourly - From 240h to 480h/1440h: six-hourly
EPT-2 RR	2024-01-01 04:00:00 - today at 00-23 UTC (every hour) *	48h, hourly
EPT-2 HRRR	2025-01-01 04:00:00 - today at 00-23 UTC (every hour) *	48h, hourly
EPT-2 Early	2025-09-01 - today at 00, 06, 12, 18 UTC	480h - From 1h to 240h: hourly - From 240h to 480h: six-hourly
EPT-2 Reasoning	2025-08-27 - today at 00, 06, 12, 18 UTC	480h - From 1h to 240h: hourly - From 240h to 480h: six-hourly

* EPT-2 RR and EPT-2 HRR have missing data on the 2025-10-20.

Extended Hindcast Data (Special Request Only)

Special Request Required: The following extended hindcast data is available but requires special access permissions and is not accessible through standard API/SDK access. Please contact [email protected] to request access.

Model	Extended Temporal Coverage	Forecast Horizon and Resolution
EPT-2 Early	2024-03-01 - 2024-03-13, 2024-06-05 - 2024-12-31 at 00, 06, 12, 18 UTC	480h - From 1h to 240h: hourly - From 240h to 480h: six-hourly

Performance Benchmarks

EPT-2 consistently outperforms other leading weather models, including:

• Microsoft Aurora

• DeepMind's GraphCast

• ECMWF's AIFS

• Our previous EPT-1.5 model

For more details on EPT-2 performance benchmarks, check out our benchmarking analysis.

Dissemination Times

For detailed dissemination times of the EPT-2 family please refer to the Dissemination Times page.