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Home > NDFD > NDFD XML Web Service

National Digital Forecast Database (NDFD) Simple Object Access Protocol (SOAP)
and Representational State Transfer (REST) XML Web Service


NOAA's National Weather Service offers several XML Services:
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  1. What is NDFD XML (DWML and TSML)?
  2. Why provide an NDFD XML Web Service?
  3. How often is NDFD XML data updated?
  4. How is NDFD XML data generated?
  5. What does NDFD XML data contain?
  6. How Do You Use the Web Service?
  7. NDFD XML Web Service Constraints, Guidelines, and Best Practices
  8. The NDFD XML Web Services REST page
  9. WHAT'S NEW: NWS NDFD XML Web Service Change Notices
  10. Information on different NDFD XML Web Service versions
  11. Point of Contact Information for NDFD XML Web Service Issues

What is NDFD XML (DWML and TSML)?

The National Digital Forecast Database (NDFD) Extensible Markup Language (XML) Web Service provides the public, government agencies, and commercial enterprises with data from the National Weather Service’s (NWS) digital forecast database. This service, which is defined in the original Service Description Document, provides NWS customers and partners the ability to request NDFD data over the internet and receive the information back in an XML format (Note, many updates, including a REST service, and an additional XML encoding standard, have been added to the NDFD XML Web Service since the original Service Description Document was drafted). The request/response process is made possible by the NDFD XML Simple Object Access Protocol (SOAP) server or Representational State Transfer (REST).

To see the details of the NDFD XML SOAP service, go to the following server link and click on NDFDgen or NDFDgenByDay:

https://digital.weather.gov/xml/SOAP_server/ndfdXMLserver.php

If the web service description provided by the SOAP server does not meet your needs, similar information is available in the following Web Service Description Language (WSDL) document:

https://digital.weather.gov/xml/wsdl/ndfdXML.wsdl

This NDFD Web Service uses XML to enhance the ease with which NWS customers, partners, and other clients, can integrate NDFD data into their computer applications.  XML is a W3C standard that allows its users to create languages with HTML-like tags and attributes.

XML schemas define the language’s vocabulary (available tags and attributes) and syntax (expected order of tags) used to encode the NDFD data returned from the web service. Knowing how NDFD XML is constructed, users can write programs to process the XML document to extract the data it contains.

Two different encoding formats of XML: DWML and TSML

This version of the NDFD XML Web Service allows the choice of two different XML formats for encoding geospatial data.

1) Digital Weather Markup Language (DWML)

The first option, DWML, is a NDFD local dialect of XML, created by the NWS. Its schema can be found at the following link:

https://digital.weather.gov/xml/schema/DWML.xsd

To see a sample DWML document that conforms to the DWML schema, click on any of the following links:

latest_DWML_time-series.txt
latest_DWML_glance.txt
latest_DWML_Summary-24hr.txt
latest_DWML_Summary-12hr.txt

2) Timeseries Markup Language (TSML)

The second option of XML formatting offered, TSML, is an Open Geospatial Consortium (OGC) recognized International encoding Standard, unlike DWML.

Because of this, TSML:

  • Offers greater interoperability: the ability of different information systems, products, or applications, whose interfaces are understood, to connect with
         other products or systems.
  • Defines the semantics of observational (in the NDFD case, forecast) data as a timeseries for data exchange.
  • Profiles the Observations and Measurements standard to define a result of type timeseries.
  • Allows the encoding of many latitude/longitude points as a collection (tsml:Collection) of observation members with each geographic point denoted as
         the feature of interest.
  • The TSML schemas can be found at the following link. The TSML schema version currently used is 1.2

    http://schemas.opengis.net/tsml

    To see a sample TSML document that conforms to the TSML schemas, click on any of the following links:

    latest_TSML_time-series.txt
    latest_TSML_glance.txt
    latest_TSML_Summary-24hr.txt
    latest_TSML_Summary-12hr.txt

    Why provide an NDFD XML Web Service?

    The National Weather Service is striving to serve society’s needs for weather and climate information by evolving its services from a text-based paradigm to one based on making NWS information available quickly, efficiently, and in convenient and understandable forms. The NDFD is one example of this transformation. The NDFD XML Web Service takes yet another step towards a digital services era by making NDFD data available for computer to computer transfer and processing. NWS customers and partners can then enhance the value of NDFD data through the creation of value added products.

    You can provide comments on this web service from the following page:

    https://www.weather.gov/contact

    How often is NDFD XML data updated?

    The NDFD is updated two times per hour. We request developers using this web service for local applications only make a request for a specific point no more than twice an hour. The database is currently updated by 25 and 55 minutes after the hour.

    How is NDFD XML data generated?

    The first step to providing NDFD XML data is the creation of the NDFD. For more information on how NDFD is created, visit the NDFD home page.

    SOAP:

    With NDFD data available, a user can create a client application that formulates and sends a SOAP request to the NDFD XML Web Service SOAP server. The SOAP request is processed, creating the DWML document which is returned to the requesting application for processing. Figure 1 provides a graphical view of the process.

    NDFD XML Web Service SOAP Process

    Figure 1.   NDFD XML Web Service SOAP Process

    REST:

    Alternatively, with the REST service, a user can generate a URL with the query parameters, and their associated key value pairs, that contains the specific NDFD request. The user can then incorporate this resulting GET HTTP REST request URL into their client applications. More information can be found in the REST section

    What does the NDFD XML Web Service contain?

    The Web Service returns forecasts for any combination of the following meteorological and climatological elements listed here:

    https://vlab.noaa.gov/documents/6609493/7858379/NDFDStatus.pdf

    (NOTE: only Long-Duration Hazards and Watches, Warnings, and Advisories are available through this service. Special Weather Statements and Short-Duration Hazards such as Tornado Warnings have valid times that can span minutes, and the data refresh for the NDFD is hourly. Thus, these shorter duration hazards can be missed due to their short temporal resolution so they are not included).

    A quick list of the NDFD elements that can be queried for in this version of the NDFD XML Web Service is here: NDFD Element Names

    These NDFD elements can be retrieved in their unsummarized form using the functions NDFDgen() or NDFDgenZip(). A subset of these elements, in summarized form over either 24 or 12 hourly forecast periods, can be retrieved using the functions NDFDgenByDay() or NDFDgenByDayZip. See the section below titled "How Do You Use the Web Service?" for more details on these four functions.

    In addition to its meteorological content, the NDFD XML returned also contains meta data about the product. For returned data encoded in DWML, a description of the meta data as well as data XML tags and attributes can be found in the Digital Weather Markup Language Specification [PDF] [HTML] [DOC]

    Finally, a list of all possible fields for icons and the weather conditions can be found here: NDFD Web Service's Icon/Weather Conditions XML fields.

    How Do You Use the Web Service?

    For REST, please visit the NDFD XML Web Service REST Home page

    SOAP:

    The first step to using the web service is to create a SOAP client.   The client creates and sends the SOAP request to the server.   The request sent by the client then invokes one of the server functions.   There are currently nine functions: NDFDgen(), NDFDgenLatLonList(), LatLonListSubgrid(), LatLonListLine(), LatLonListZipCode(), LatLonListSquare(), CornerPoints(), NDFDgenByDay(), and NDFDgenByDayLatLonList().   See the tables below for required user supplied input consisting of the input query parameter names, and their resulting values:

      NDFDgen() function: Returns DWML or TSML encoded NDFD data for a point

      latitude Decimal 39.21 The WGS84 latitude of the point for which you want NDFD data. North latitude is positive.
      longitude Decimal -77.08 The WGS84 longitude of the point for which you want NDFD data. West longitude is negative.
      product string time-series,
      glance
      There are two products. The “time-series” product returns all data between the start and end times for the user selected weather parameters in the weatherParameters input query below. The “glance” product returns all data between the start and end times for the parameters maxt, mint, sky, wx, icons, and wwa (hazards), by default. Note, when the “glance” (“Weather at a Glance”) product is chosen, a choice of elements is not permitted.
      XMLformat string DWML,
      TSML
      The XML encoding type data is returned in. Value can be either TSML or DWML. If not specified, the default value is DWML.
      startTime XML Date string 2020-04-27T12:00:00 The beginning time for which you want NDFD data.   If the string is empty, the start time is assumed to be the earliest available time in the database. This input is only needed if one wants to shorten the time window data is to be retrieved for (less than entire 7 days worth), e.g. if user wants data for days 2-5.
      endTime XML Date string 2020-04-30T12:00:00 The ending time for which you want NDFD data.   If the string is empty, the end time is assumed to be the last available time in the database. This input is only needed if one wants to shorten The time window data is to be retrieved for (less than entire 7 days worth), e.g. if user wants data for days 2-5.
      Unit string e,
      m
      The unit data is to be formatted in. The default value is U.S. Standard, or English units ("e"). A value of "m" will return data in Metric, or SI units (the International System of Units). If the string is empty, data will be returned in U.S. Standard units, thus the input is only needed for metric conversion.
      weatherParameters Array of Booleans maxt = TRUE The NDFD parameters that you are requesting.   For valid inputs see the NDFD Element Names Page. Set value to 1 for parameters wanted.

      You can view an example of how to invoke NDFDgen() by selecting "NDFD Data For Single Point" on the following web page, which represents a URL client to the SOAP service.

      https://digital.weather.gov/xml/SOAP_server/ndfdXML.htm

      You can see a sample SOAP request for the NDFDgen() interface at
      https://digital.weather.gov/xml/docs/SOAP_Requests/NDFDgen.xml

      NDFDgenLatLonList() function: Returns DWML or TSML encoded NDFD data for a list of points

      listLatLon string 38.99,-77.02 39.70,-104.80 List of WGS84 latitude and longitude pairs for the points for which you want NDFD data.   Each point's latitude and longitude value is seperated by a comma. Each pair (one latitude and longitude value) is separated by a space. To reduce resources on the web service, the number of points requested can not exceed 100.
      product string time-series,
      glance
      There are two products.   The “time-series” product returns all data between the start and end times for the selected weather parameters in the weatherParameters input query below.   The “glance” product returns all data between the start and end times for the parameters maxt, mint, sky, wx, icons, and wwa (hazards). Note, when the “glance” (“Weather at a Glance”) product is chosen, a choice of elements is not permitted.
      XMLformat string DWML,
      TSML
      The XML encoding type data is returned in. Value can be either TSML or DWML. If not specified, the default value is DWML.
      startTime XML Date string 2020-04-27T12:00:00 The beginning time for which you want NDFD data.   If the string is empty, the start time is assumed to be the earliest available time in the database. This input is only needed if one wants to shorten the time window data is to be retrieved for (less than entire 7 days worth), e.g. if user wants data for days 2-5.
      endTime XML Date string 2020-04-30T12:00:00 The ending time for which you want NDFD data.   If the string is empty, the end time is assumed to be the last available time in the database. This input is only needed if one wants to shorten the time window data is to be retrieved for (less than entire 7 days worth), e.g. if user wants data for days 2-5.
      Unit string e,
      m
      The unit data is to be formatted in. The default value is U.S. Standard, or English units ("e"). A value of "m" will return data in Metric, or SI units (The International System of Units). If the string is empty, data will be returned in U.S. Standard units, thus the input is only needed for metric conversion.
      weatherParameters Array of Booleans maxt = TRUE The NDFD parameters that you are requesting.   For valid inputs see the NDFD Element Names Page. Set value to 1 for parameters wanted.

      You can view an example of how to invoke NDFDgenLatLonList() by selecting "NDFD Data For Multiple Points" on the following web page, which represents a URL client to the SOAP server. To reduce resources on the web service, the number of points requested can not exceed 100.

      https://digital.weather.gov/xml/SOAP_server/ndfdXML.htm

      You can see a sample SOAP request for the NDFDgenLatLonList() interface at
      https://digital.weather.gov/xml/docs/SOAP_Requests/NDFDgenLatLonList.xml

      LatLonListSubgrid() function: Returns the WGS84 latitude and longitude values of all the NDFD grid points within a rectangular subgrid as defined by points at the lower left and upper right corners of the rectangle. The returned list of points is suitable for input into NDFDgenLatLonList(), NDFDgenByDayLatLonList(), and GmlLatLonList() which will return NDFD data for those points. NOTE: The subgrid locations will only form a rectangle when viewed in the NDFD projection applicable to the grid.

      XMLformat string DWML,
      TSML
      The XML encoding type data is returned in. Value can be either TSML or DWML. If not specified, the default value is DWML.
      listType string Subgrid The "shape" of the data to be retrieved.
      lowerLeftLatitude Decimal 33.88 The WGS84 latitude of the lower left point of the rectangular subgrid for which you want NDFD grid points.   North latitude is positive.
      lowerLeftLongitude Decimal -80.06 The WGS84 longitude of the lower left point of the rectangular subgrid for which you want NDFD grid points.   West longitude is negative.
      upperRightLatitude Decimal 33.88 The WGS84 latitude of the upper right point of the rectangular subgrid for which you want NDFD grid points.   North latitude is positive.
      upperRightLongitude Decimal -80.06 The WGS84 longitude of the upper right point of the rectangular subgrid for which you want NDFD grid points.   West longitude is negative.
      resolution Decimal 20.0 The default resolution for NDFD data is typically 2.5km. However, users can request latitude and longitude values for resolutions greater ( 5km, 10km, 15km, 20km, etc.) than the native resolution so as to reduce the number of points returned.

      You can view an example of how to invoke LatLonListSubgrid() by selecting "Grid Points For Subgrid" on the following URL client web page.

      https://digital.weather.gov/xml/SOAP_server/ndfdXML.htm

      You can see a sample SOAP request for the LatLonListSubgrid() interface at
      https://digital.weather.gov/xml/docs/SOAP_Requests/LatLonListSubgrid.xml

      LatLonListLine() function: Returns the WGS84 latitude and longitude values for all points on a line defined by the line's end points. The returned list of points is suitable for input into NDFDgenLatLonList(), NDFDgenByDayLatLonList(), and GmlLatLonList() which will return NDFD data for those points. NOTE: The list of locations will only form a straight line when viewed in the NDFD projection applicable to the grid.

      XMLformat string DWML,
      TSML
      The XML encoding type data is returned in. Value can be either TSML or DWML. If not specified, the default value is DWML.
      listType string Line The "shape" of the data to be retrieved.
      endPoint1Lat Decimal 39.00 The WGS84 latitude of the first end point of the line for which you want NDFD grid points.   North latitude is positive.
      endPoint1Lon Decimal -77.00 The WGS84 longitude of the first end point of the line for which you want NDFD grid points.   West longitude is negative.
      endPoint2Lat Decimal 39.00 The WGS84 latitude of the second end point of the line for which you want NDFD grid points.   North latitude is positive.
      endPoint2Lon Decimal -77.00 The WGS84 longitude of the second end point of the line for which you want NDFD grid points.   West longitude is negative.

      You can view an example of how to invoke LatLonListLine() by selecting "Grid Points For A Line" on the following URL client web page.

      https://digital.weather.gov/xml/SOAP_server/ndfdXML.htm

      You can see a sample SOAP request for the LatLonListLine() interface at
      https://digital.weather.gov/xml/docs/SOAP_Requests/LatLonListLine.xml

      LatLonListZipCode() function: Returns the WGS84 latitude and longitude values for one or more zip codes (50 United States and Puerto Rico). The returned list of points is suitable for input into NDFDgenLatLonList(), NDFDgenByDayLatLonList(), and GmlLatLonList() which will return NDFD data for those points.

      zipCodeList string 20910 The zip code of the area for which you want NDFD grid points.
      XMLformat string DWML,
      TSML
      The XML encoding type data is returned in. Value can be either TSML or DWML. If not specified, the default value is DWML.
      listType string zipCode The "shape" of the data to be retrieved.

      You can view an example of how to invoke LatLonListZipCode() by selecting "Grid Points For A Zip Code" on the following URL client web page.

      https://digital.weather.gov/xml/SOAP_server/ndfdXML.htm

      You can see a sample SOAP request for the LatLonListZipCode() interface at
      https://digital.weather.gov/xml/docs/SOAP_Requests/LatLonListZipCode.xml

      LatLonListSquare() function: Returns the WGS84 latitude and longitude values for a rectangle defined by a center point and distances in the latitudinal and longitudinal directions. The returned list of points is suitable for input into NDFDgenLatLonList(), NDFDgenByDayLatLonList(), and GmlLatLonList() which will return NDFD data for those points. NOTE: The subgrid locations will only form a rectangle when viewed in the NDFD projection applicable to the grid.

      XMLformat string DWML,
      TSML
      The XML encoding type data is returned in. Value can be either TSML or DWML. If not specified, the default value is DWML.
      listType string Square The "shape" of the data to be retrieved.
      centerPointLat Decimal 39.00 The WGS84 latitude of the center or the rectangle for which you want NDFD grid points.   North latitude is positive.
      centerPointLon Decimal -77.00 The WGS84 longitude of the center or the rectangle for which you want NDFD grid points.   West longitude is negative.
      distanceLat Decimal 50.0 The distance from the center point in the latitudinal direction to the rectangle's East/West oriented sides.
      distanceLon Decimal 50.0 The distance from the center point in the longitudinal direction to the rectangle's North/South oriented side.
      resolution Decimal 20.0 The default resolution for NDFD data is typically 2.5km. However, users can request latitude and longitude values for resolutions greater ( 5km, 10km, 15km, 20km, etc.) than the native resolution so as to reduce the number of points returned.

      You can view an example of how to invoke LatLonListSquare() by selecting "Grid Points For Subgrid (Central Point)" on the following web page, which represents a URL client to the SOAP server.

      https://digital.weather.gov/xml/SOAP_server/ndfdXML.htm

      You can see a sample SOAP request for the LatLonListSquare() interface at
      https://digital.weather.gov/xml/docs/SOAP_Requests/LatLonListSquare.xml

      CornerPoints() function: Returns the WGS84 latitude and longitude values for the corners of an NDFD grid as well as the resolution required to retrieve the entire grid and still stay under the maximum allowed point restriction.

      XMLformat string DWML,
      TSML
      The XML encoding type data is returned in. Value can be either TSML or DWML. If not specified, the default value is DWML.
      listType string Corners The "shape" of the data to be retrieved.
      sector string conus One of the NDFD grids (conus, alaska, nhemi, guam, hawaii, npacocn, and puertori).

      You can view an example of how to invoke CornerPoints() by selecting "Corner Grid Points" on the following web page, which represents a URL client to the SOAP server.

      https://digital.weather.gov/xml/SOAP_server/ndfdXML.htm

      You can see a sample SOAP request for the CornerPoints() interface at
      https://digital.weather.gov/xml/docs/SOAP_Requests/CornerPoints.xml

      GmlLatLonList() function: Returns Digital Weather Geography Markup Language (GML) encoded NDFD data for a list of points at a single valid time.

      listLatLon string 38.99,-77.02 39.70,-104.80 List of WGS84 latitude and longitude pairs for the points for which you want NDFD data.   Each point's latitude and longitude value is seperated by a comma. Each pair (one latitude and longitude value) is separated by a space. To reduce resources on the web service, the number of points requested can not exceed 100.
      requestedTime XML Date string 2020-04-27T12:00:00 The time for which you want NDFD data.
      featureType string Forecast_Gml2Point GML 2 Compliant Data Structure: Forecast_Gml2Point
      GML 3 Compliant Data Structures: Forecast_GmlsfPoint, Forecast_GmlObs, NdfdMultiPointCoverage
      KML 2 Compliant Data Structure: Ndfd_KmlPoint
      weatherParameters Array of Booleans maxt = TRUE The NDFD parameters that you are requesting.   For valid inputs see the NDFD Element Names Page. Set value to 1 for parameters wanted.

      You can view an example of how to invoke GmlLatLonList() by selecting "NDFD Data Encoded in GML for Single Time" on the following web page, which represents a URL client to the SOAP server. To reduce resources on the web service, the number of points requested can not exceed 100.

      https://digital.weather.gov/xml/SOAP_server/ndfdXML.htm

      You can see a sample SOAP request for the GmlLatLonList() interface at
      https://digital.weather.gov/xml/docs/SOAP_Requests/GmlLatLonList.xml

      GML is also an OGC International Standard for encoding geospatial data. As a result, GML and the application schema derived from it are supported by a number of GIS applications. There are examples of importing GML-encoded NDFD data into several applications at the following tutorials link:

      Tutorials on integrating the NDFD Web Service and clients like ArcGIS, Google Earth, and Google Maps.

      In addition to GML, the GmlLatLonList() service function can return Keyhole Markup Language (KML) encoded NDFD data. KML can be viewed with freely available tools like Google Earth and is also recognized by the OGC.

      GmlTimeSeries() function: Returns Digital Weather in Geography Markup Language (GML) encoded NDFD data for a list of points during a user specified time period.

      listLatLon string 38.99,-77.02 39.70,-104.80 List of WGS84 latitude and longitude pairs for the points for which you want NDFD data.   Each point's latitude and longitude value is seperated by a comma. Each pair (one latitude and longitude value) is separated by a space. To reduce resources on the web service, the number of points requested can not exceed 100.
      startTime XML Date string 2020-01-01T14:00:00 The start time for which you want NDFD data.
      endTime XML Date string 2020-01-05T23:00:00 The end time for which you want NDFD data.
      compType string Between Comparison type. Can be IsEqual, Between, GreatThan, GreaterThanOrEqual, LessThan, or LessThanOrEqual.
      featureType string Forecast_Gml2Point GML 2 Compliant Data Structure: Forecast_Gml2Point
      GML 3 Compliant Data Structures: Forecast_GmlsfPoint, Forecast_GmlObs, NdfdMultiPointCoverage
      KML 2 Compliant Data Structure: Ndfd_KmlPoint
      propertyName comma delimited list maxt,mint,wx The NDFD element that you are requesting.   For valid inputs see the NDFD Element Names Page. Set value to 1 for parameters wanted.

      You can view an example of how to invoke GmlTimeSeries() by selecting "NDFD Data Encoded in GML for Time Period" on the following web page, which represents a URL client to the SOAP server. To reduce resources on the web service, the number of points requested can not exceed 100.

      https://digital.weather.gov/xml/SOAP_server/ndfdXML.htm

      You can see a sample SOAP request for the GmlLatLonList() interface at
      https://digital.weather.gov/xml/docs/SOAP_Requests/GmlTimeSeries.xml

      GML is also an OGC International Standard for encoding geospatial data. As a result, GML and the application schema derived from it are supported by a number of GIS applications. There are examples of importing GML-encoded NDFD data into several applications at the following tutorials link:

      Tutorials on integrating the NDFD Web Service and clients like ArcGIS, Google Earth, and Google Maps.

      In addition to GML, the GmlLatLonList() service function can return Keyhole Markup Language (KML) encoded NDFD data. KML can be viewed with freely available tools like Google Earth.

      NDFDgenByDay() function: Returns DWML or TSML encoded NDFD data for a point. Data for each point is summarized over either 24- or 12-hour forecast time periods.

      NOTE: There is no choice by user of meteorological elements for these summarization functions. The following summarized elements are always returned by default: Maximum Temperature, Minimum Temperature, 12 Hourly Probability of Precipitation, Weather, Icons, and Hazards (Watches, Warnings, and Advisories).


      latitude Decimal 39.00 The WGS84 latitude of the point for which you want NDFD data.   North latitude is positive.
      longitude Decimal -77.00 The WGS84 longitude of the point for which you want NDFD data.   West longitude is negative.
      startDate XML Date string 2020-04-27 The beginning day for which you want NDFD data.   If the string is empty, the start date is assumed to be the earliest available day in the database. This input is only needed if one wants to shorten the time window data is to be retrieved for (less than entire 7 days worth), e.g. if user wants data for days 2-5.
      numDays Integer 7 The number of days worth of NDFD data you want. Default will be all available data in the database. This input is only needed if one wants to shorten the time window data is to be retrieved for (less than entire 7 days worth), e.g. if user wants data for days 2-5.
      Unit string e,
      m
      The unit data is to be formatted in. The default value is U.S. Standard, or English units ("e"). A value of "m" will return data in Metric, or SI units (The International System of Units). If the string is empty, data will be returned in U.S. standard units, thus the input is only needed for metric conversion.
      XMLformat string DWML,
      TSML
      The XML encoding type data is returned in. Value can be either TSML or DWML. If not specified, the default value is DWML.
      format string 12 hourly,
      24 hourly
      There are two formats.   The “24 hourly” format returns NDFD data summarized for a 24 hour forecast period running from 6:00 AM to 6:00 AM.   The “12 hourly” format summarizes NDFD data into two 12 hour forecast periods per day that run from 6:00 AM to 6:00 PM and 6:00 PM to 6:00 AM

      You can view an example of how to invoke NDFDgenByDay() by selecting "NDFD Data For Single Point" on the following web page, which represents a URL client to the SOAP server.

      https://digital.weather.gov/xml/SOAP_server/ndfdSOAPByDay.htm

      You can see a sample SOAP request for the NDFDgenByDay() interface at
      https://digital.weather.gov/xml/docs/SOAP_Requests/NDFDgenByDay.xml

      NDFDgenByDayLatLonList() function: Returns DWML or TSML encoded NDFD data for a list of points. Data for each point is summarized over either 24- or 12-hour forecast time periods.

      NOTE: There is no choice by user of meteorological elements for these summarization functions. The following summarized elements are always returned by default: Maximum Temperature, Minimum Temperature, 12 Hourly Probability of Precipitation, Weather, Icons, and Hazards (Watches, Warnings, and Advisories).


      listLatLon Decimal 38.99,-77.02 39.70,-104.80 List of WGS84 latitude and longitude pairs for the points for which you want NDFD data.   Each point's latitude and longitude value is seperated by a comma. Each pair (one latitude and longitude value) is separated by a space. To reduce resources on the web service, the number of points requested can not exceed 100.
      startDate XML Date string 2020-04-27 The beginning day for which you want NDFD data.   If the string is empty, the start date is assumed to be the earliest available day in the database.
      numDays Integer 7 The number of days worth of NDFD data you want.
      Unit string e,
      m
      The unit data is to be formatted in. The default value is U.S. Standard, or English units ("e"). A value of "m" will return data in Metric, or SI units (The International System of Units). If the string is empty, data will be returned in U.S. standard units, thus the input is only needed for metric conversion.
      XMLformat string DWML,
      TSML
      The XML encoding type data is returned in. Value can be either TSML or DWML. If not specified, the default value is DWML.
      format string 12 hourly,
      24 hourly
      There are two formats.   The “24 hourly” format returns NDFD data summarized for a 24 hour forecast period running from 6:00 AM to 6:00 AM.   The “12 hourly” format summarizes NDFD data into two 12 hour forecast periods per day that run from 6:00 AM to 6:00 PM and 6:00 PM to 6:00 AM

      You can view an example of how to invoke NDFDgenByDayLatLonList() by selecting "NDFD Data For Multiple Points" on the following web page, which represents a URL client to the SOAP server. To reduce resources on the web service, the number of points requested can not exceed 100.

      https://digital.weather.gov/xml/SOAP_server/ndfdSOAPByDay.htm

      You can see a sample SOAP request for the NDFDgenByDayLatLonList() interface at
      https://digital.weather.gov/xml/docs/SOAP_Requests/NDFDgenByDayLatLonList.xml

      NDFDgenByDayMultiCities() function: Returns DWML or TSML encoded NDFD data for a predefined list of cities. The cities are grouped into a number of subsets to facilitate requesting data. You can view the cities in each group by clicking on the links under Description in the table below. Data for each point is summarized over either 24- or 12-hour forecast time periods.

      NOTE: There is no choice by user of meteorological elements for these summarization functions. The following summarized elements are always returned by default: Maximum Temperature, Minimum Temperature, 12 Hourly Probability of Precipitation, Weather, Icons, and Hazards (Watches, Warnings, and Advisories).


      a
      citiesLevel Integer 12 1 = Primary Cities Diagram (list of cities here).
      2 = Secondary Cities Diagram (list of cities here).
      3 = Cities that increase data density across the US, Diagram (cities 1 - 200), (list of cities here).
      4 = Cities that increase data density across the US, Diagram (cities 201 - 304), (list of cities here).
      12 = Combines cities in 1 and 2 above, Diagram (list of cities here).
      34 = Combines cities in 3 and 4 above, Diagram (list of cities here).
      1234 = Combines cities in 1, 2, 3, and 4 above, Diagram (list of cities here).
      startDate XML Date string 2020-04-27 The beginning day for which you want NDFD data.   If the string is empty, the start date is assumed to be the earliest available day in the database. This input is only needed if one wants to shorten the time window data is to be retrieved for (less than entire 7 days worth), e.g. if user wants data for days 2-5.
      numDays Integer 7 The number of days worth of NDFD data you want. If the string is empty, numDays is assumed to be the full amount of days in the database. This input is only needed if one wants to shorten the time window data is to be retrieved for (less than entire 7 days worth), e.g. if user wants data for days 2-5.
      Unit string e,
      m
      The unit data is to be formatted in. The default value is U.S. Standard, or English units ("e"). A string value of "m" will return data in Metric, or SI units (The International System of Units). If the string is empty, data will be returned in U.S. Standard units, thus the input is only needed for metric conversion.
      XMLformat string DWML,
      TSML
      The XML encoding type data is returned in. Value can be either TSML or DWML. If not specified, the default value is DWML.
      format string 12 hourly,
      24 hourly
      There are two formats.   The “24 hourly” format returns NDFD data summarized for a 24 hour forecast period running from 6:00 AM to 6:00 AM.   The “12 hourly” format summarizes NDFD data into two 12 hour forecast periods per day that run from 6:00 AM to 6:00 PM and 6:00 PM to 6:00 AM

      You can view an example of how to invoke NDFDgenByDayMultiCities() by selecting "NDFD Data For NDFD Cities" on the following web page, which represents a URL client to the SOAP server.

      https://digital.weather.gov/xml/SOAP_server/ndfdSOAPByDay.htm

    Once the SOAP server returns the XML document back, the client can then parse the XML using any number of open source software packages.

    All latitude and longitude values provided as input or in the output XML are based on the World Geodetic System 1984 (WGS84). For more information on the NDFD spatial reference system see the NDFD Spatial Reference System page.

    NDFD XML Web Service Constraints, Guidelines, and Best Practices

    Please consult the NDFD Web Services Use Guidelines to ease strain on the NDFD XML Web Service.

    The NDFD XML Web Services REST page

    Please visit the following web page to access the Web Service via REST:

      NDFD XML Web Service REST Home page

    WHAT'S NEW: NWS XML Web Services Change Notices

    Below are listed recent updates and change notices for the NWS NDFD XML Web Service. A complete listing is available. An RSS feed of the change notices is also available. These notices are used to announce major changes such as resolution changes, schema changes, new services, new meteorological elements offered, etc.

    NDFD-XML: WSDL difference for NDFD XML Web Service on new AWS architecture.
    For our legacy SOAP users who access the web service via the SOAP POST method, note the updated WSDL . A new parameter called XMLformat is now in all the functions. If your application that requests NDFD XML via SOAP POST, you may need to adjust your request to accommodate this new parameter. Note, the order of the parameters matter and needs to match the order of the elements in the WSDL. Also, make sure SOAP POST requests access the endpoint graphical.weather.gov/xml/ with https and not http.

    NDFD-XML: Graphical.weather.gov/xml/ on different architecture.
    In April 2024, the NDFD XML Web Service at https://graphical.weather.gov/xml/ is now hosted on Amazon Web Service (AWS) architecture, instead of the National Weather Service's Internet Dissemination System (NIDS). Queries can be made to https://graphical.weather.gov/xml/ or https://digital.weather.gov/xml/. Graphical.weather.gov/xml/ will now return full resoluction NDFD, which is hourly temporal resoluction and 2.5 kilometer spatial resolution (before, it was 3 hourly temporal resolution and 5 kilometer resolution.)

    NDFD-XML: Heat Risk Weather Element added to NDFD XML Web Service
    Heat Risk element will be added for dissemination through the NDFD XML Web Service. They will be available for points in the Conus sector only. For more information see Description Document . This experimental element will be available through the NDFD XML Web Service located at https://digital.weather.gov/xml. The name of the element as the query parameter in the service is "heatrisk" as seen here in the WSDL (https://digital.weather.gov/xml/SOAP_server/ndfdXMLserver.php?wsdl).

    NDFD-XML: Five Experimental Aviation Weather Elements added to NDFD XML Web Service
    Five new Aviation elements will be added for dissemination through the NDFD XML Web Service. They will be available for points in the Conus and Puerto Rico sectors. For more information see the Product Description Document (PDD). These experimental elements will be available for comment through May 23, 2023. These elements include Ceiling Height (defined as the lowest cloud base, measured in feet, where the cumulative sky cover is > 50%, and uses the threshold for the qualitative term “broken” or “BKN”), Visibility (values are consistent with information in the weather and hazard grids. Units are statute miles (SM) with a resolution of 0.25 SM from 0 to 1.50, inclusive, and a resolution of SM from 2 to 10 SM, inclusive. Values > 10 SM are set to 10 SM), and Low Level Wind Shear. There are 3 separate Low Level Wind Shear elements: Height (the top of the low-level wind shear layer), Wind Speed, and Wind Direction. The name of the elements in the service are "ceil", "vis", "llwsdist", "llwswindspd", and "llwswinddir", as seen here in the WSDL (https://digital.weather.gov/xml/SOAP_server/ndfdXMLserver.php?wsdl).

    NDFD-XML: New AWS NDFD XML Web Service (digital.weather.gov/xml) to limit the number of lat/lon points in a query to 100 to limit resource strain on the web service. For more information, see our NDFD XML Web Service Use Guidelines page at https://digital.weather.gov/xml/mdl/XML/Design/WebServicesUseGuidelines.php.


    NDFD-XML: AWS NDFD XML Web Service at Full Resolution
    The new NDFD XML Web Service (digital.weather.gov/xml) is at full resolution for points queried in the CONUS sector. The spatial and temporal resolution in the NDFD as compared to the operational system on graphical (graphical.weather.gov/xml) will be available at 2.5km spatial resolution for all forecast times and at 1 hour temporal resolution for the first 36 hours from NDFD issuance time (on graphical, the spatial resolution is 5km and 3 hourly). These are the finest spatial and temporal resolutions at which Weather Forecast Offices in the Conterminous United States (CONUS) provide forecasts. More information is here in the Technical Implementation Notice and also: here.

    Information on different NDFD XML web service versions

    URLs that begin with 'graphical.weather.gov/xml' go to the coarse-resolution (3-hour, 5km) legacy operational NWS servers. This service has NDFD elements that were operationally available when upgrades to this on-prem service were frozen about 2016. A list of elements available for this version of the NDFD XML Web Service is here: NDFD Elements on graphical

    URLs that begin with 'preview.weather.gov/xml' go to the fine-resolution (1-hour, 2.5km) experimental on-prem NWS servers. This has all NDFD elements available at lower resolution on graphical, in higher resolution form. It also contains NDFD elements that were experimentally available at finer resolution when upgrades to the on-prem service on graphical were frozen about 2016. A list of elements available for this version of the NDFD XML Web Service is here: NDFD Elements on preview

    In response to performance issues on both on-prem XML web services listed above (graphical and preview), the NWS was testing NDFD XML web services for new NDFD elements on Amazon Web Services (AWS). For more information, see: NDFD on AWS. The AWS version of the NDFD XML web service is this current one, hosted on this page at https://digital.weather.gov/xml/. Prior, to April 2022, it disseminated only those elements (20) the NDFD had developed since 2016. It also did not disseminate the "Weather At A Glance", 12 hourly, or 24 hourly summary products.

    URLs that begin with 'digital.weather.gov/xml', as of April 2022, now access the fine-resolution (1-hour, 2.5km) prototype servers on AWS. This service now provides the newer (post-2016) NDFD elements that are not available via the on-prem (graphical and preview) NWS services. It also contains the full suite of all available NDFD elements. A list of the NDFD elements available for this version of the NDFD XML Web Service is here: NDFD Elements on digital

    Point of Contact Information for NDFD XML Web Service Issues

    To submit a ticket for an issue with the NWS XML Web Services, please email the NOAA ServiceNow Platform at nsdesk@servicenowservices.com.

     

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