Hourly Precipitation Data (HPD) is digital data set DSI-3240, archived at the National Climatic Data Center (NCDC). The primary source of data for this file is approximately 5,500 US National Weather Service (NWS), Federal Aviation Administration (FAA), and cooperative observer stations in the United States of America, Puerto Rico, the US Virgin Islands, and various Pacific Islands. The earliest data dates vary considerably by state and region: Maine, Pennsylvania, and Texas have data since 1900. The western Pacific region that includes Guam, American Samoa, Marshall Islands, Micronesia, and Palau have data since 1978. Other states and regions have earliest dates between those extremes. The latest data in all states and regions is from the present day. The major parameter in DSI-3240 is precipitation amounts, which are measurements of hourly or daily precipitation accumulation. Accumulation was for longer periods of time if for any reason the rain gauge was out of service or no observer was present. DSI 3240_01 contains data grouped by state; DSI 3240_02 contains data grouped by year.

Global Historical Climatology Network-hourly (GHCNh) is a multisource collection of weather station (meteorological) observations from the late 18th Century to the present from fixed weather stations over land across the globe. It is replacing the Integrated Surface Dataset (ISD) and will be used to generate the Local Climatological Data and Global Summary of the Day datasets. It is constructed to align with GHCN daily. Version 1 contains approximately 110 separate data sources and will be updated daily using the United States Air Force and NOAA Surface Weather Observations data streams. GHCNh v1 contains the following variables: altimeter; dew_point_temperature; precipitation; pressure_3hr_change; pres_wx_AU1; pres_wx_AU2; pres_wx_AU3; pres_wx_AW1; pres_wx_AW2; pres_wx_AW3; pres_wx_MW1; pres_wx_MW2; pres_wx_MW3; relative_humidity; Remarks; sea_level_pressure; sky_cov_baseht_1; sky_cov_baseht_2; sky_cov_baseht_3; sky_cover_1; sky_cover_2; sky_cover_3; station_level_pressure; dry bulb temperature; visibility; wet_bulb_temperature; wind_direction; wind_gust; wind_speed.

Global Surface Summary of the Day is derived from The Integrated Surface Hourly (ISH) dataset. The ISH dataset includes global data obtained from the USAF Climatology Center, located in the Federal Climate Complex with NCDC. The latest daily summary data are normally available 1-2 days after the date-time of the observations used in the daily summaries. The online data files begin with 1929 and are at the time of this writing at the Version 8 software level. Over 9000 stations' data are typically available. The daily elements included in the dataset (as available from each station) are: Mean temperature (.1 Fahrenheit) Mean dew point (.1 Fahrenheit) Mean sea level pressure (.1 mb) Mean station pressure (.1 mb) Mean visibility (.1 miles) Mean wind speed (.1 knots) Maximum sustained wind speed (.1 knots) Maximum wind gust (.1 knots) Maximum temperature (.1 Fahrenheit) Minimum temperature (.1 Fahrenheit) Precipitation amount (.01 inches) Snow depth (.1 inches) Indicator for occurrence of: Fog, Rain or Drizzle, Snow or Ice Pellets, Hail, Thunder, Tornado/Funnel Cloud Global summary of day data for 18 surface meteorological elements are derived from the synoptic/hourly observations contained in USAF DATSAV3 Surface data and Federal Climate Complex Integrated Surface Hourly (ISH). Historical data are generally available for 1929 to the present, with data from 1973 to the present being the most complete. For some periods, one or more countries' data may not be available due to data restrictions or communications problems. In deriving the summary of day data, a minimum of 4 observations for the day must be present (allows for stations which report 4 synoptic observations/day). Since the data are converted to constant units (e.g, knots), slight rounding error from the originally reported values may occur (e.g, 9.9 instead of 10.0). The mean daily values described below are based on the hours of operation for the station. For some stations/countries, the visibility will sometimes 'cluster' around a value (such as 10 miles) due to the practice of not reporting visibilities greater than certain distances. The daily extremes and totals--maximum wind gust, precipitation amount, and snow depth--will only appear if the station reports the data sufficiently to provide a valid value. Therefore, these three elements will appear less frequently than other values. Also, these elements are derived from the stations' reports during the day, and may comprise a 24-hour period which includes a portion of the previous day. The data are reported and summarized based on Greenwich Mean Time (GMT, 0000Z - 2359Z) since the original synoptic/hourly data are reported and based on GMT.

The Cooperative Observer Program (COOP) Hourly Precipitation Data (HPD) consists of quality controlled precipitation amounts, which are measurements of hourly accumulation of precipitation, including rain and snow for approximately 2,000 observing stations around the country, and several U.S. territories in the Caribbean and Pacific from the National Weather Service (NWS) Fischer-Porter Network. This new version of COOP HPD with faster automations due updated stations will result in faster access for the public. The data are from 1940 to present, depending upon when each station was installed. These stations, nearly all of which were part of HPD version 1, also known as DSI-3240, were gradually upgraded from paper punch tape data recording systems to a more modern electronic data logger system from 2004-2013. The 15-min gauge depth time series are processed at NCEI via automated quality control and filtering algorithms to identify and remove spurious observations from noise and malfunctioning equipment, and also those due to natural phenomena such as evaporation and the necessary occasional emptying of the gauge. Hourly precipitation totals are then computed from the 15-min data and are quality controlled by a suite of automated algorithms that combine checks on the daily and hourly time scale. Data and metadata are ingested on a daily basis and combined in a single integrated dataset. As with the legacy punch paper instrumentation, the electronic loggers record rain gauge depth every 15 minutes. Monthly site visits to each station are still performed, but instead of collecting punched paper (that would subsequently need conversion to a digital record via a MITRON reader), data are downloaded from the station's datalogger to a memory stick and centrally collected at the local Weather Forecast Office (WFO) for all stations in the WFO area. The WFO subsequently combines all data into a single tar file and transfers the data to NCEI via ftp upload nominally each month. This updated HPD includes the historical data from the punch paper era and the recent digital era in order to provide the full period of record for each location. These data are formatted consistent with practices for NCEI Global In-situ datasets.

Local Climatological Data (LCD) are summaries of climatological conditions from airport and other prominent weather stations managed by NWS, FAA, and DOD. The product includes hourly observations and associated remarks, and a record of hourly precipitation for the entire month. Also included are daily summaries summarizing temperature extremes, degree days, precipitation amounts and winds. The tabulated monthly summaries in the product include maximum, minimum, and average temperature, temperature departure from normal, dew point temperature, average station pressure, ceiling, visibility, weather type, wet bulb temperature, relative humidity, degree days (heating and cooling), daily precipitation, average wind speed, fastest wind speed/direction, sky cover, and occurrences of sunshine, snowfall and snow depth. The source data is global hourly (DSI 3505) which includes a number of quality control checks.

Standard hourly observations taken at Weather Bureau/National Weather Service offices and airports throughout the United States. Hourly observations began during the aviation boom in the late 1920s-early 1930s, and continue through Automated Surface Observing Stations (ASOS) today. Files scanned from original manuscript records of raw meteorological data collected by first and second order stations located in the U.S., U.S. Pacific Islands, U.S. Virgin Islands, Puerto Rico, and by military weather stations located worldwide. The vast majority of records are available online, but some records are still only available in the physical format only.

The Analysis Of Record for Calibration (AORC) is a gridded record of near-surface weather conditions covering the continental United States and Alaska and their hydrologically contributing areas. It is defined on a latitude/longitude spatial grid with a mesh length of 30 arc seconds (~800 m), and a temporal resolution of one hour. Elements include hourly total precipitation, temperature, specific humidity, terrain-level pressure, downward longwave and shortwave radiation, and west-east and south-north wind components. It spans the period from 1979 across the Continental U.S. (CONUS) and from 1981 across Alaska, to the near-present (at all locations). This suite of eight variables is sufficient to drive most land-surface and hydrologic models and is used as input to the National Water Model (NWM) retrospective simulation. While the native AORC process generates netCDF output, the data is post-processed to create a cloud optimized Zarr formatted equivalent for dissemination using cloud technology and infrastructure.

AORC Version 1.1 dataset creation
The AORC dataset was created after reviewing, identifying, and processing multiple large-scale, observation, and analysis datasets. There are two versions of The Analysis Of Record for Calibration (AORC) data.

The initial AORC Version 1.0 dataset was completed in November 2019 and consisted of a grid with 8 elements at a resolution of 30 arc seconds. The AORC version 1.1 dataset was created to address issues "see Table 1 in Fall et al., 2023" in the version 1.0 CONUS dataset. Full documentation on version 1.1 of the AORC data and the related journal publication are provided below.

The native AORC version 1.1 process creates a dataset that consists of netCDF files with the following dimensions: 1 hour, 4201 latitude values (ranging from 25.0 to 53.0), and 8401 longitude values (ranging from -125.0 to -67).

The data creation runs with a 10-day lag to ensure the inclusion of any corrections to the input Stage IV and NLDAS data.

Note - The full extent of the AORC grid as defined in its data files exceed those cited above; those outermost rows and columns of data grids are filled with missing values and are the remnant of an early set of required AORC extents that have since been adjusted inward.

AORC Version 1.1 Zarr Conversion

The goal for converting the AORC data from netCDF to Zarr was to allow users to quickly and efficiently load/use the data. For example, one year of data takes 28 mins to load via NetCDF while only taking 3.2 seconds to load via Zarr (resulting in a substantial increase in speed). For longer periods of time, the percentage increase in speed using Zarr (vs NetCDF) is even higher. Using Zarr also leads to less memory and CPU utilization.

It was determined that the optimal conversion for the data was 1 year worth of Zarr files with a chunk size of 18MB. The chunking was completed across all 8 variables. The chunks consist of the following dimensions: 144 time, 128 latitude, and 256 longitude. To create the files in the Zarr format, the NetCDF files were rechunked using chunk() and "Xarray". After chunking the files, they were converted to a monthly Zarr file. Then, each monthly Zarr file was combined using "to_zarr" to create a Zarr file that represents a full year

Users wanting more than 1 year of data will be able to utilize Zarr utilities/libraries to combine multiple years up to the span of the full data set.

There are eight variables representing the meteorological conditions
Total Precipitaion (APCP_surface)

1. Hourly total precipitation (kgm-2 or mm) for Calibration (AORC) dataset
   

Air Temperature (TMP_2maboveground)

1. Temperature (at 2 m above-ground-level (AGL)) (K)
   

Specific Humidity (SPFH_2maboveground)

1. Specific humidity (at 2 m AGL) (g g-1)
   

Downward Long-Wave Radiation Flux (DLWRF_surface)

1. longwave (infrared)
2. radiation flux (at the surface) (W m-2)
   

Downward Short-Wave Radiation Flux (DSWRF_surface)

1. Downward shortwave (solar)
2. radiation flux (at the surface) (W m-2)
   

Pressure (PRES_surface)

1. Air pressure (at the surface) (Pa)
   

**U-Component of Wind (UGRD_10maboveground)"
1)U (west-east) - components of the wind (at 10 m AGL) (m s-1)
**V-Component of Wind (VGRD_10maboveground)"

1. V (south-north) - components of the wind (at 10 m AGL) (m s-1)
   
   

Precipitation and Temperature

The gridded AORC precipitation dataset contains one-hour Accumulated Surface Precipitation (APCP) ending at the “top” of each hour, in liquid water-equivalent units (kg m-2 to the nearest 0.1 kg m-2), while the gridded AORC temperature dataset is comprised of instantaneous, 2 m above-ground-level (AGL) temperatures at the top of each hour (in Kelvin, to the nearest 0.1).

Specific Humidity, Pressure, Downward Radiation, Wind

The development process for the six additional dataset components of the Conus AORC [i.e., specific humidity at 2m above ground (kg kg-1); downward longwave and shortwave radiation fluxes at the surface (W m-2); terrain-level pressure (Pa); and west-east and south-north wind components at 10 m above ground (m s-1)] has two distinct periods, based on datasets and methodology applied: 1979–2015 and 2016–present.

The Integrated Surface Database (ISD) consists of global hourly and synoptic observations compiled from numerous sources into a gzipped fixed width format. ISD was developed as a joint activity within Asheville's Federal Climate Complex. The database includes over 35,000 stations worldwide, with some having data as far back as 1901, though the data show a substantial increase in volume in the 1940s and again in the early 1970s. Currently, there are over 14,000 "active" stations updated daily in the database. The total uncompressed data volume is around 600 gigabytes; however, it continues to grow as more data are added. ISD includes numerous parameters such as wind speed and direction, wind gust, temperature, dew point, cloud data, sea level pressure, altimeter setting, station pressure, present weather, visibility, precipitation amounts for various time periods, snow depth, and various other elements as observed by each station.

The NCEP operational Global Forecast System analysis and forecast grids are on a 0.25 by 0.25 global latitude longitude grid. Grids include analysis and forecast time steps at a 3 hourly interval from 0 to 240, and a 12 hourly interval from 240 to 384. Model forecast runs occur at 00, 06, 12, and 18 UTC daily. For real-time data access please use the NCEP data server [http://www.nco.ncep.noaa.gov/pmb/products/gfs/].

NOTE: This dataset now has a direct, continuously updating copy located on AWS (https://noaa-gfs-bdp-pds.s3.amazonaws.com/index.html [https://noaa-gfs-bdp-pds.s3.amazonaws.com/index.html]). Therefore, the RDA will stop updating this dataset in early 2025

The U.S. Hourly Climate Normals for 1981 to 2010 are 30-year averages of meteorological parameters for thousands of U.S. stations located across the 50 states, as well as U.S. territories, commonwealths, the Compact of Free Association nations, and one station inCanada. NOAA Climate Normals are a large suite of data products that provide users with many tools to understand typical climate conditions for thousands of locations across the United States. As many NWS stations as possible are used, including those from the NWS Cooperative Observer Program (COOP) Network as well as some additional stations that have a Weather Bureau Army-Navy (WBAN) station identification number, including stations from the Climate Reference Network (CRN). The comprehensive U.S. Climate Normals dataset includes various derived products including daily air temperature normals (including maximum and minimum temperature normal, heating and cooling degree day normal, and others), precipitation normals (including snowfall and snow depth, percentiles, frequencies and other), and hourly normals (all normal derived from hourly data including temperature, dew point, heat index, wind chill, wind, cloudiness, heating and cooling degree hours, pressure normals). Users can access the data either by product or by station. Included in the dataset is extensive documentation to describe station metadata, filename descriptions, and methodology of producing the data. All data utilized in the computation of the 1981-2010 Climate Normals were taken from the ISD Lite (a subset of derived Integrated Surface Data), the Global Historical Climatology Network-Daily dataset, and standardized monthly temperature data (COOP). These source datasets (including intermediate datasets used in the computation of products) are also archived at the NOAA NCDC.

This map contains continuously updated U.S. tornado reports, wind storm reports and hail storm reports. Click each feature to receive information about the specific location and read a short description about the issue.Now contains ALL available Incident Report types, for a total of 15, not just Hail; Wind; and Tornados.See new layer for details or Feature Layer Item with exclusive Past 24-Hour ALL Storm Reports Layer.Each layer is updated 4 times hourly from data provided by NOAA’s National Weather Service Storm Prediction Center.A full archive of storm events can be accessed from the NOAA National Centers for Environmental Information.SourceNOAA Storm Prediction Center https://www.spc.noaa.gov/climo/reportsNOAA ALL Storm Reports layer https://www.spc.noaa.gov/exper/reportsSample DataSee Sample Layer Item for sample data during inactive periods!Update FrequencyThe service is updated every 15 minutes using the Aggregated Live Feeds MethodologyArea CoveredCONUS (Contiguous United States)What can you do with this layer?This map service is suitable for data discovery and visualization.Change the symbology of each layer using single or bi-variate smart mapping. For instance, use size or color to indicate the intensity of a tornado.Click each feature to receive information about the specific location and read a short description about the issue.Query the attributes to show only specific event types or locations.Revisions:Aug 10, 2021: Updated Classic Layers to use new Symbols. Corrected Layer Order Presentation. Updated Thumbnail.Aug 8, 2021: Update to layer-popups, correcting link URLs. Expanded length of 'Comment' fields to 1kb of text. New Layer added that includes ALL available Incident Types and Age in 'Hours Old'.This map is provided for informational purposes and is not monitored 24/7 for accuracy and currency.If you would like to be alerted to potential issues or simply see when this service will update next, please visit our Live Feed Status Page.

U.S. 15 Minute Precipitation Data is digital data set DSI-3260, archived at the National Climatic Data Center (NCDC). This is precipitation data. The primary source of data for this file is approximately 2,000 mostly U.S. weather stations operated or managed by the U.S. National Weather Service. Stations are primary, secondary, or cooperative observer sites that have the capability to measure precipitation at 15 minute intervals. This dataset contains 15-minute precipitation data (reported 4 times per hour, if precip occurs) for U.S. stations along with selected non-U.S. stations in U.S. territories and associated nations. It includes major city locations and many small town locations. Daily total precipitation is also included as part of the data record. NCDC has in archive data from most states as far back as 1970 or 1971, and continuing to the present day. The major parameter is precipitation amounts at 15 minute intervals, when precipitation actually occurs.

Release of the hourly database containing 55 cruises spanning over 31 years, including the historical data from 12 cruises done in the 1990's (Fairall et al., 2003) and 9 cruises of the PACS/EPIC dataset. Data collected from these cruises are critical for supporting the study of physical oceanography, air-sea interaction, tropical meteorology, as well as global weather and climate variability and predictability. This includes improvement to our fundamental understanding of these processes in the ocean and their influence around the globe including the Continental United States. The data will also support improvement and validation of prediction models including parameterizations. Sensible heat flux was computed from vertical velocity - sonic temperature covariance. The humidity contribution to sonic temperature was removed using the bulk latent heat flux. acknowledgement=NOAA Global Ocean Monitoring and Observing (GOMO) program cdm_data_type=Trajectory cdm_trajectory_variables=cruise_name comment=Corrections and Data Quality Notes not contained in global or variable attributes: Unavailable data, bad data, and data within restricted Exclusive Economic Zones were assigned _FillValue = -9999. Please use the variables named flag_bad_ship and flag_bad_bulk to further mask out questionable or non-ideal data points depending on the application for state variables and bulk fluxes respectively. comment2=Sensible heat flux was computed from vertical velocity - sonic temperature covariance. The humidity contribution to sonic temperature was removed using the bulk latent heat flux. comment3=A correction to account for biases in gas concentration measurements has been applied on the covariance and ID latent heat fluxes. See Fratini et al. 2014 for more details. comment4=Data from the 2004 New England Air Quality Study (NEAQS-04) are included in this dataset but it has to be noted that during that project we found significant suppression of the transfer coefficients for momentum, sensible heat, and latent heat; mainly because our measurements at 18-m height did not realize the full surface flux in these shallower boundary layer conditions. (Fairall et al., 2006). Conventions=CF-1.6, ACCD-1.3, COARDS, ACDD-1.3 coverage_content_type=physicalMeasurement, qualityInformation, modelResult, coordinate date_metadata_modified=2023-04-18T13:10:40Z Easternmost_Easting=179.73351 featureType=Trajectory geospatial_lat_bounds=POLYGON [-179.833, 179.734, -53.754, 69.934] geospatial_lat_max=69.933717 geospatial_lat_min=-53.753807 geospatial_lat_units=degrees_north geospatial_lon_max=179.73351 geospatial_lon_min=-179.83283 geospatial_lon_units=degrees_east geospatial_vertical_max=0.014330280134111055 geospatial_vertical_min=1.7080496969024725E-4 geospatial_vertical_positive=down geospatial_vertical_units=m history=v0: original data, v1: first release id=doi = not yet assigned infoUrl=https://psl.noaa.gov/boundary-layer/ institution=(1) NOAA Physical Sciences Lab (PSL); (2) CIRES Cooperative Institute for Research in Environmental Sciences at the University of Colorado Boulder in partnership with NOAA PSL instrument_vocabulary=GCMD Version 12.3 keywords_library=GCMD Version 12.3 keywords_vocabulary=GCMD Science Keywords licence=Please acknowledge data according to global attribute info: acknowledgement, creator_name, creator_institution. These data may be redistributed and used without restriction. naming_authority=gov.noaa.ncei Northernmost_Northing=69.933717 platform=refer to platform_name variable that contains names of the different platforms from which the datasets were collected platform_vocabulary=GCMD Version 12.3 processing_level=processed and quality controlled program=Funding agencies: NOAA Global Ocean Monitoring and Observing (GOMO) program project=refer to cruise_name variable for project names of various datasets references=Fairall et al. 1996a JGR https://doi.org/10.1029/95JC03190 ...Fairall et al. 1996b JGR https://doi.org/10.1029/95JC03205 .... Fairall et al. 2003 JClim https://doi.org/10.1175/1520-0442(2003)016%3C0571:BPOASF%3E2.0.CO;2 ... Edson et al. 2013 JPO with corrigendum: the value should be m = 0.0017, and not m = 0.017 as originally appeared https://doi.org/10.1175/JPO-D-12-0173.1 ... Fratini et al. 2014https://doi.org/10.5194/bg-11-1037-2014 ... Fairall et al. 2006 https://doi.org/10.1029/2006JD007597 sea_name=Northwest, Equatorial and SouthEast Pacific Ocean; North Atlantic Ocean; Davis Strait; Labrador Sea; South Atlantic Ocean; Bay of Bengal; Indian Ocean; Tasman Sea source=observations from NOAA PSL sensors (no subscript, most accurate) and the ship permanent sensors (_ship subscript, less accurate), derivations from those observations using eddy covariance and inertial dissipation methods of estimating fluxes, model results from COARE 3.6 bulk air-sea flux algorithm. Wave parameters were not used as input to COARE since they were either unavailable or not consistently available on all projects. Also True water-relative wind speed was used as input to COARE when available. Otherwise when not available the true wind speed was used instead. sourceUrl=(local files) Southernmost_Northing=-53.753807 standard_name_vocabulary=CF Standard Name Table v70 time_coverage_duration=31 years time_coverage_end=2021-08-31T23:00:00Z time_coverage_resolution=PT60.M time_coverage_start=1991-11-22T11:41:00Z Westernmost_Easting=-179.83283

The NOAA National Water Model Retrospective dataset contains input and output from multi-decade CONUS retrospective simulations. These simulations used meteorological input fields from meteorological retrospective datasets. The output frequency and fields available in this historical NWM dataset differ from those contained in the real-time operational NWM forecast model.

One application of this dataset is to provide historical context to current near real-time streamflow, soil moisture and snowpack conditions. The retrospective data can be used to infer flow frequencies and perform temporal analyses with hourly streamflow output and 3-hourly land surface output. This dataset can also be used in the development of end user applications which require a long baseline of data for system training or verification purposes.

Currently there are three versions of the NWM retrospective dataset

A 42-year (February 1979 through December 2020) retrospective simulation using version 2.1 of the National Water Model. A 26-year (January 1993 through December 2018) retrospective simulation using version 2.0 of the National Water Model. A 25-year (January 1993 through December 2017) retrospective simulation using version 1.2 of the National Water Model.

Version 2.1 uses forcings from the Office of Water Prediction Analysis of Record for Calibration (AORC) dataset while Version 2.0 and version 1.2 use input meteorological forcing from the North American Land Data Assimilation (NLDAS) data set. Note that no streamflow or other data assimilation is performed within any of the NWM retrospective simulations.

NWM Retrospective data is available in two formats, NetCDF and Zarr. The NetCDF files contain the full set of NWM output data, while the Zarr files contain a subset of NWM output fields that vary with model version.

NWM V2.1: All model output and forcing input fields are available in the NetCDF format. All model output fields along with the precipitation forcing field are available in the Zarr format. NWM V2.0: All model output fields are available in NetCDF format. Model channel output including streamflow and related fields are available in Zarr format. NWM V1.2: All model output fields are available in NetCDF format.

A table listing the data available within each NetCDF and Zarr file is located in the 'documentation page'. This data includes meteorological NWM forcing inputs along with NWM hydrologic and land surface outputs, and varies by version number.

Documentation

https://github.com/NOAA-Big-Data-Program/bdp-data-docs/blob/main/nwm/README.md

Update Frequency

No updates

License

Open Data. There are no restrictions on the use of this data.

Last Revised: February 2016 Map InformationThis nowCOAST™ time-enabled map service provides maps depicting the latest surface weather and marine weather observations at observing sites using the international station model. The station model is a method for representing information collected at an observing station using symbols and numbers. The station model depicts current weather conditions, cloud cover, wind speed, wind direction, visibility, air temperature, dew point temperature, sea surface water temperature, significant wave height, air pressure adjusted to mean sea level, and the change in air pressure over the last 3 hours. The circle in the model is centered over the latitude and longitude coordinates of the station. The total cloud cover is expressed as a fraction of cloud covering the sky and is indicated by the amount of circle filled in; however, all cloud cover values are presently displayed using the "Missing" symbol due to a problem with the source data. Present weather information is also not available for display at this time. Wind speed and direction are represented by a wind barb whose line extends from the cover cloud circle towards the direction from which the wind is blowing. The short lines or flags coming off the end of the long line are called barbs, which indicate wind speed in knots. Each normal barb represents 10 knots, while short barbs indicate 5 knots. A flag represents 50 knots. If there is no wind barb depicted, an outer circle around the cloud cover symbol indicates calm winds.Due to software limitations, the observations included in this map service are organized into three separate group layers: 1) Wind velocity (wind barb) observations, 2) Cloud Cover observations, and 3) All other observations, which are displayed as numerical values (e.g. Air Temperature, Wind Gust, Visibility, Sea Surface Temperature, etc.).Additionally, due to the density of weather/ocean observations in this map service, each of these group data layers has been split into ten individual "Scale Band" layers, with each one visible for a certain range of map scales. Thus, to ensure observations are displayed at any scale, users should make sure to always specify all ten corresponding scale band layers in every map request. This will result in the scale band most appropriate for your present zoom level being shown, resulting in a clean, uncluttered display. As you zoom in, additional observations will appear.The observations in this nowCOAST™ map service are updated approximately every 10 minutes. However, since the reporting frequency varies by network or station, the observations for a particular station may update only once per hour. For more detailed information about layer update frequency and timing, please reference the nowCOAST™ Dataset Update Schedule.Background InformationThe maps of near-real-time surface weather and ocean observations are based on non-restricted data obtained from the NWS Family of Services courtesy of NESDIS/OPSD and also the NWS Meteorological Assimilation Data Ingest System (MADIS). The data includes observations from terrestrial and maritime observing stations from the U.S.A. and other countries. For terrestrial networks, the platforms include but are not limited to ASOS, AWOS, RAWS, non-automated stations, U.S. Climate Reference Networks, many U.S. Geological Survey Stations via NWS HADS, several state DOT Road Weather Information Systems, and U.S. Historical Climatology Network-Modernization. For maritime areas, the platforms include NOS/CO-OPS National Water Level Observation Network (NWLON), NOS/CO-OPS Physical Oceanographic Real-Time System (PORTS), NWS/NDBC Fixed Buoys, NDBC Coastal-Marine Automated Network (C-MAN), drifting buoys, ferries, Regional Ocean Observing System (ROOS) coastal stations and buoys, and ships participating in the Voluntary Ship Observing (VOS) Program. Observations from MADIS are updated approximately every 10 minutes in the map service and those from NESDIS are updated every hour. However, not all stations report that frequently. Many stations only report once per hour sometime between 15 minutes before the hour and 30 minutes past the hour. For these stations, new observations will not appear until approximately 23 minutes past top of the hour for land-based stations and 33 minutes past the top of the hour for maritime stations.Time InformationThis map service is time-enabled, meaning that each individual layer contains time-varying data and can be utilized by clients capable of making map requests that include a time component.In addition to ArcGIS Server REST access, time-enabled OGC WMS 1.3.0 access is also provided by this service.This particular service can be queried with or without the use of a time component. If the time parameter is specified in a request, the data or imagery most relevant to the provided time value, if any, will be returned. If the time parameter is not specified in a request, the latest data or imagery valid for the present system time will be returned to the client. If the time parameter is not specified and no data or imagery is available for the present time, no data will be returned.This service is configured with time coverage support, meaning that the service will always return the most relevant available data, if any, to the specified time value. For example, if the service contains data valid today at 12:00 and 12:10 UTC, but a map request specifies a time value of today at 12:07 UTC, the data valid at 12:10 UTC will be returned to the user. This behavior allows more flexibility for users, especially when displaying multiple time-enabled layers together despite slight differences in temporal resolution or update frequency.When interacting with this time-enabled service, only a single instantaneous time value should be specified in each request. If instead a time range is specified in a request (i.e. separate start time and end time values are given), the data returned may be different than what was intended.Care must be taken to ensure the time value specified in each request falls within the current time coverage of the service. Because this service is frequently updated as new data becomes available, the user must periodically determine the service's time extent. However, due to software limitations, the time extent of the service and map layers as advertised by ArcGIS Server does not always provide the most up-to-date start and end times of available data. Instead, users have three options for determining the latest time extent of the service:Issue a returnUpdates=true request (ArcGIS REST protocol only) for an individual layer or for the service itself, which will return the current start and end times of available data, in epoch time format (milliseconds since 00:00 January 1, 1970). To see an example, click on the "Return Updates" link at the bottom of the REST Service page under "Supported Operations". Refer to the ArcGIS REST API Map Service Documentation for more information.Issue an Identify (ArcGIS REST) or GetFeatureInfo (WMS) request against the proper layer corresponding with the target dataset. For raster data, this would be the "Image Footprints with Time Attributes" layer in the same group as the target "Image" layer being displayed. For vector (point, line, or polygon) data, the target layer can be queried directly. In either case, the attributes returned for the matching raster(s) or vector feature(s) will include the following:validtime: Valid timestamp.starttime: Display start time.endtime: Display end time.reftime: Reference time (sometimes referred to as issuance time, cycle time, or initialization time).projmins: Number of minutes from reference time to valid time.desigreftime: Designated reference time; used as a common reference time for all items when individual reference times do not match.desigprojmins: Number of minutes from designated reference time to valid time.Query the nowCOAST™ LayerInfo web service, which has been created to provide additional information about each data layer in a service, including a list of all available "time stops" (i.e. "valid times"), individual timestamps, or the valid time of a layer's latest available data (i.e. "Product Time"). For more information about the LayerInfo web service, including examples of various types of requests, refer to the nowCOAST™ LayerInfo Help DocumentationReferencesNWS, 2013: Sample Station Plot, NWS/NCEP/WPC, College Park, MD (Available at http://www.wpc.ncep.noaa.gov/html/stationplot.shtml).NWS, 2013: Terminology and Weather Symbols, NWS/NCEP/OPC, College Park, MD (Available at http://www.opc.ncep.noaa.gov/product_description/keyterm.shtml).NWS, 2013: How to read Surface weather maps, JetStream an Online School for Weather (Available at http://www.srh.noaa.gov/jetstream/synoptic/wxmaps.htm).

The NCEP operational Global Forecast System auxiliary analysis and forecast grids are on a 0.25 by 0.25 global latitude longitude grid. Grids include analysis and forecast time steps at a 3 hourly interval from 0 to 240, and a 12 hourly interval from 240 to 384. Model forecast runs occur at 00, 06, 12, and 18 UTC daily. For real-time data access please use the NCEP data server [http://www.nco.ncep.noaa.gov/pmb/products/gfs/].

The National Data Buoy Center (NDBC) distributes meteorological data from moored buoys maintained by NDBC and others. Moored buoys are the weather sentinels of the sea. They are deployed in the coastal and offshore waters from the western Atlantic to the Pacific Ocean around Hawaii, and from the Bering Sea to the South Pacific. NDBC's moored buoys measure and transmit barometric pressure; wind direction, speed, and gust; air and sea temperature; and wave energy spectra from which significant wave height, dominant wave period, and average wave period are derived. Even the direction of wave propagation is measured on many moored buoys. See https://www.ndbc.noaa.gov/measdes.shtml for a description of the measurements.

The source data from NOAA NDBC has different column names, different units, and different missing values in different files, and other problems (notably, lots of rows with duplicate or different values for the same time point). This dataset is a standardized, reformatted, and lightly edited version of that source data, created by NOAA NMFS SWFSC ERD (email: erd.data at noaa.gov). Before 2020-01-29, this dataset only had the data that was closest to a given hour, rounded to the nearest hour. Now, this dataset has all of the data available from NDBC with the original time values. If there are multiple source rows for a given buoy for a given time, only the row with the most non-NaN data values is kept. If there is a gap in the data, a row of missing values is inserted (which causes a nice gap when the data is graphed). Also, some impossible data values are removed, but this data is not perfectly clean. This dataset is now updated every 5 minutes.

This dataset has both historical data (quality controlled, before 2023-12-01T00:00:00Z) and near real time data (less quality controlled, which may change at any time, from 2024-01-01T00:00:00Z on). cdm_data_type=TimeSeries cdm_timeseries_variables=station, longitude, latitude contributor_name=NOAA NDBC contributor_role=Source of data. Conventions=COARDS, CF-1.6, ACDD-1.3, NCCSV-1.2 Easternmost_Easting=179.001 featureType=TimeSeries geospatial_lat_max=71.758 geospatial_lat_min=-55.0 geospatial_lat_units=degrees_north geospatial_lon_max=179.001 geospatial_lon_min=-177.75 geospatial_lon_units=degrees_east geospatial_vertical_positive=down geospatial_vertical_units=m history=Around the 25th of each month, erd.data@noaa.gov downloads the latest yearly and monthly historical .txt.gz files from https://www.ndbc.noaa.gov/data/historical/stdmet/ and generates one historical .nc file for each station. erd.data@noaa.gov also downloads all of the 45day near real time .txt files from https://www.ndbc.noaa.gov/data/realtime2/ and generates one near real time .nc file for each station. Every 5 minutes, erd.data@noaa.gov downloads the list of latest data from all stations for the last 2 hours from https://www.ndbc.noaa.gov/data/latest_obs/latest_obs.txt and updates the near real time .nc files. id=cwwcNDBCMet infoUrl=https://www.ndbc.noaa.gov/ institution=NOAA NDBC, NOAA NMFS SWFSC ERD keywords_vocabulary=GCMD Science Keywords naming_authority=gov.noaa.pfeg.coastwatch Northernmost_Northing=71.758 project=NOAA NDBC and NOAA NMFS SWFSC ERD quality=Automated QC checks with periodic manual QC source=station observation sourceUrl=https://www.ndbc.noaa.gov/ Southernmost_Northing=-55.0 standard_name_vocabulary=CF Standard Name Table v70 subsetVariables=station, longitude, latitude testOutOfDate=now-25minutes time_coverage_end=2025-03-23T05:25:00Z time_coverage_start=1970-02-26T20:00:00Z Westernmost_Easting=-177.75

NOTE: Version 3 of GHCN has been discontinued at NCEI, and so this dataset is no longer being updated. Version 4 of GHCN can be accessed ... href="https://www.ncdc.noaa.gov/data-access/land-based-station-data/land-based-datasets/global-historical-climatology-network-monthly-version-4">here. The Global Historical Climatology Network (GHCN) is a baseline network of long-running surface global stations for the purpose of monitoring and detecting climate change. Monthly-summarized data from various global sources are processed on a daily basis assembled into version 3 of NCDC's GHCNM dataset. The CISL Research Data Archive is hosting a copy of the monthly-average surface temperatures in support of UCAR's Global Learning and Observation to Benefit the Environment (GLOBE) program.

This report pertains to the roughly 9,000 NWS Cooperative Network sites whose observations are published in NCDC's Climatological Data or Hourly Precipitation Data publications. It is a compilation of elements observed and/or reported for all published stations in the Cooperative network. It uses repeating groups of details by station, data program, element and equipment. The PHR replaces the legacy Climatological Data Master Station Index (CDMSI) and Hourly Precipitation Data Master Station Index (HPDMSI) and provides a more complete, historical view of element details.The PHR replaces the legacy Climatological Data Master Station Index (CDMSI) and Hourly Precipitation Data Master Station Index (HPDMSI) and provides a more complete, historical view of element details.

This dataset contains Raleigh Durham International Airport weather data pulled from the NOAA web service described at Climate Data Online: Web Services Documentation. We have pulled this data and converted it to commonly used units. This dataset is an archive - it is not being updated.