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NOAA HRRR analysis

Spatial domain Continental United States
Spatial resolution 3 km
Time domain 2014-10-01 00:00:00 UTC to Present
Time resolution 1 hour

STAC (browse)

The High-Resolution Rapid Refresh (HRRR) is a NOAA real-time 3-km resolution, hourly updated, cloud-resolving, convection-allowing atmospheric model, initialized by 3km grids with 3km radar assimilation. Radar data is assimilated in the HRRR every 15 min over a 1-h period adding further detail to that provided by the hourly data assimilation from the 13km radar-enhanced Rapid Refresh.

This analysis dataset is an archive of the model's best estimate of past weather. It is created by concatenating the first hour of each historical forecast to provide a dataset with dimensions time, x, and y.

This dataset uses the native HRRR Lambert Conformal Conic projection, with spatial indexing along the x and y dimensions. The example notebook shows how to use the embedded spatial reference to select geographic areas of interest.

Related Datasets

Examples

Quickstart (Github)
Quickstart (Colab)
dynamical.org - NOAA HRRR analysis
Temperature at a specific place and time
import dynamical_catalog  # dynamical-catalog>=0.5.0

ds = dynamical_catalog.open("noaa-hrrr-analysis")
ds["temperature_2m"].sel(time="2025-01-01T00", x=0, y=0, method="nearest").compute()

Dimensions

min max units
time 2014-10-01T00:00:00Z Present seconds since 1970-01-01
x -2697520.143 2696479.857 m
y -1587306.153 1586693.847 m

Variables

Access a variable by its name (the bold identifier, e.g. ds["categorical_freezing_rain_surface"]).

Dimensions: time × y × x

variable units
categorical_freezing_rain_surface Categorical freezing rain (cfrzr)0=no; 1=yes 1
categorical_ice_pellets_surface Categorical ice pellets (cicep)0=no; 1=yes 1
categorical_rain_surface Categorical rain (crain)0=no; 1=yes 1
categorical_snow_surface Categorical snow (csnow)0=no; 1=yes 1
composite_reflectivity Maximum/Composite radar reflectivity (refc) dBZ
dew_point_temperature_2m 2 metre dewpoint temperature (2d) degree_Celsius
downward_long_wave_radiation_flux_surface Surface downward long-wave radiation flux (sdlwrf) W m-2
downward_short_wave_radiation_flux_surface Surface downward short-wave radiation flux (sdswrf) W m-2
geopotential_height_cloud_ceiling Geopotential height (gh) m
percent_frozen_precipitation_surface Percent frozen precipitation (cpofp) percent
precipitable_water_atmosphere Precipitable water (pwat) kg m-2
precipitation_surface Precipitation rate (prate)Average precipitation rate since the previous forecast step. Units equivalent to mm/s. kg m-2 s-1
pressure_reduced_to_mean_sea_level Pressure reduced to MSL (prmsl) Pa
pressure_surface Surface pressure (sp) Pa
relative_humidity_2m 2 metre relative humidity (2r) percent
snow_area_fraction_surface Snow cover (snowc) 1
snow_thickness_surface Snow depth (sde) m
snow_water_equivalent_surface Snow depth water equivalent (sd) m
snowfall_surface Total snowfall rate (tsrate)Average snowfall rate since the previous forecast step. m s-1
temperature_2m 2 metre temperature (2t) degree_Celsius
total_cloud_cover_atmosphere Total cloud cover (tcc) percent
wind_gust_surface Wind speed (gust) (gust) m s-1
wind_u_10m 10 metre U wind component (10u) m s-1
wind_u_80m 80 metre U wind component (80u) m s-1
wind_v_10m 10 metre V wind component (10v) m s-1
wind_v_80m 80 metre V wind component (80v) m s-1

Don't see what you're looking for? Let us know at [email protected].

Details

License

Dataset licensed under CC BY 4.0.

Attribution and citation

NOAA NWS NCEP HRRR data processed by dynamical.org from NOAA Open Data Dissemination archives.

Or NOAA HRRR from dynamical.org.

DOI

Construction

HRRR starts a new model run every hour and dynamical.org has created this analysis by concatenating the first step of each forecast along the time dimension. Accumulated variables (e.g. precipitation) are read from the second step of the previous hour's forecast.

Data availability

There are a significant number of missing source files before August 2018 (HRRR v1 and v2 period), and a small number from August 2018 to December 2020 (HRRR v3 period).

downward_long_wave_radiation_flux_surface and relative_humidity_2m are unavailable before August 2016 (HRRR v1 period).

This dataset has NaN values where source data are unavailable.

Source

The source grib files this archive is constructed from are provided by NOAA Open Data Dissemination (NODD) and accessed from the AWS Open Data Registry. Operational data is additionally accessed from NOAA NOMADS.

Storage

Storage for this dataset is generously provided by Source Cooperative, a Radiant Earth initiative. Icechunk storage generously provided by AWS Open Data.

Chunks & shards

This dataset is stored in Zarr format, which splits each variable into a grid of chunks — the smallest unit read from storage. Chunks are grouped into larger shards (the objects actually written to storage), which keeps the object count manageable for long-archive datasets. When possible, aligning your reads with this dataset's chunk grid can significantly improve data access speed.

The element count and coordinate span of this dataset:

dimension chunk shard
time 2160 (90 days) 2160 (90 days)
y 45 (135 km) 540 (1620 km)
x 45 (135 km) 450 (1350 km)
uncompressed 16.7 MiB 2.0 GiB

The same values are published in the dynamical-org:chunking field of this dataset's STAC collection metadata.

Compression

The data values in this dataset have been rounded in their binary floating point representation to improve compression. See Klöwer et al. 2021 for more information on this approach. The exact number of rounded bits can be found in our reformatting code.

Knowing the moment a forecast is ready